Ashwood P, Van de Water J. Is autism an autoimmune disease? Autoimmun Rev. 2004 Nov;3(7-8):557-62.
Department of Internal Medicine, Division of Rheumatology, and UC Davis M.I.N.D. Institute, University of California, Davis, CA 95616, USA.
Autism spectrum disorder (ASD) is a spectrum of behavioral anomalies characterized by impaired social interaction and communication, often accompanied by repetitive and stereotyped behavior. The condition manifests within the first 3 years of life and persists into adulthood. There are numerous hypotheses regarding the etiology and pathology of ASD, including a suggested role for immune dysfunction. However, to date, the evidence for involvement of the immune system in autism has been inconclusive. While immune system abnormalities have been reported in children with autistic disorder, there is little consensus regarding the nature of these differences which include both enhanced autoimmunity and reduced immune function. In this review, we discuss current findings with respect to immune function and the spectrum of autoimmune phenomena described in children with ASD.
PMID: 15546805 [PubMed - indexed for MEDLINE]
Ashwood P, Willis S, Van de Water J. The immune response in autism: a new frontier for autism research. J Leuk Biol. 2006 Jul:80;1-15.
Medical Microbiology and Immunology and the M.I.N.D. Institute, University of California Davis, Sacramento, CA 95817, USA. [email protected]
Autism spectrum disorders (ASD) are part of a broad spectrum of neurodevelopmental disorders known as pervasive developmental disorders, which occur in childhood. They are characterized by impairments in social interaction, verbal and nonverbal communication and the presence of restricted and repetitive stereotyped behaviors. At the present time, the etiology of ASD is largely unknown, but genetic, environmental, immunological, and neurological factors are thought to play a role in the development of ASD. Recently, increasing research has focused on the connections between the immune system and the nervous system, including its possible role in the development of ASD. These neuroimmune interactions begin early during embryogenesis and persist throughout an individual's lifetime, with successful neurodevelopment contingent upon a normal balanced immune response. Immune aberrations consistent with a dysregulated immune response, which so far, have been reported in autistic children, include abnormal or skewed T helper cell type 1 (T(H)1)/T(H)2 cytokine profiles, decreased lymphocyte numbers, decreased T cell mitogen response, and the imbalance of serum immunoglobulin levels. In addition, autism has been linked with autoimmunity and an association with immune-based genes including human leukocyte antigen (HLA)-DRB1 and complement C4 alleles described. There is potential that such aberrant immune activity during vulnerable and critical periods of neurodevelopment could participate in the generation of neurological dysfunction characteristic of ASD. This review will examine the status of the research linking the immune response with ASD.
PMID: 16698940 [PubMed - indexed for MEDLINE]
Bach JF. Infections and autoimmune diseases. J Autoimmun. 2005;25 Suppl:74-80.
Laboratoire d'Immunologie, Hôpital Necker, 161 rue de Sèvres, 75743 Paris Cedex 15, France. [email protected]
The high percentage of disease-discordant pairs of monozygotic twins demonstrates the central role of environmental factors in the etiology of autoimmune diseases. Efforts were first focussed on the search for triggering factors. The study of animal models has clearly shown that infections may trigger autoimmune diseases, as in the case of Coxsackie B4 virus in type I diabetes and the encephalomyocarditis virus in autoimmune myositis, two models in which viruses are thought to act by increasing immunogenicity of autoantigens secondary to local inflammation. The induction of a Guillain-Barré syndrome in rabbits after immunization with a peptide derived from Campylobacter jejuni is explained by mimicry between C. jejuni antigens and peripheral nerve axonal antigens. Other models involve chemical modification of autoantigens, as in the case of iodine-induced autoimmune thyroiditis. These mechanisms have so far only limited clinical counterparts (rheumatic fever, Guillain-Barré syndrome and drug-induced lupus or myasthenia gravis) but one may assume that unknown viruses may be at the origin of a number of chronic autoimmune diseases, such as type I diabetes and multiple sclerosis) as illustrated by the convergent data incriminating IFN-alpha in the pathophysiology of type I diabetes and systemic lupus erythematosus. Perhaps the difficulties met in identifying the etiologic viruses are due to the long lag time between the initial causal infection and onset of clinical disease. More surprisingly, infections may also protect from autoimmune diseases. Western countries are being confronted with a disturbing increase in the incidence of most immune disorders, including autoimmune and allergic diseases, inflammatory bowel diseases, and some lymphocyte malignancies. Converging epidemiological evidence indicates that this increase is linked to improvement of the socio-economic level of these countries, posing the question of the causal relationship and more precisely the nature of the link. Epidemiological and clinical data support the hygiene hypothesis according to which the decrease of infections observed over the last three decades is the main cause of the incessant increase in immune disorders. The hypothesis does not exclude an etiological role for specific pathogens in a given immune disorder as might notably be the case in inflammatory bowel diseases. Even in this setting, infections could still have a non-specific protective role. Independently of the need for confirmation by epidemiological prospective studies, the hygiene hypothesis still poses numerous questions concerning the nature of protective infectious agents, the timing of their involvement with regard to the natural history of immune diseases and, most importantly, the mechanisms of protection. Four orders of mechanisms are being explored. Antigenic competition is the first hypothesis (immune responses against pathogens compete with autoimmune and allergic responses). This is probably an important mechanism but its modalities are still elusive in spite of considerable experimental data. Its discussion in the context of homeostatic regulation of lymphocyte pools has shed new light on this hypothesis with possible competition for self MHC peptide recognition and interleukin-7. Another hypothesis deals with immunoregulation. Infectious agents stimulate a large variety of regulatory cells (Th2, CD25+, Tr1, NKT, ...) whose effects extend to other specificities than those which triggered their differentiation (bystander suppression). Infectious agents may also intervene through components which are not recognized as antigens but bind to specific receptors on cells of the immune system. Major attention has recently been drawn to Toll receptors (expressed on macrophages and possibly on regulatory T cells) and TIM proteins present on Th cells, which may express the function of the virus receptor (as in the case of the Hepatitis A virus and Tim-1). Experimental data will be presented to support each of these hypotheses. In any event, the final proof of principle will be derived from therapeutic trials where the immune disorders in question will be prevented or better cured by products derived from protective infectious agents. Numerous experimental data are already available in several models. Preliminary results have also been reported in atopic dermatitis using bacterial extracts and probiotics.
PMID: 16278064 [PubMed - indexed for MEDLINE]
Campbell DB, Sutcliffe JS, Ebert PJ, Militerni R, Bravaccio C, Trillo S, Elia M, Schneider C, Melmed R, Sacco R, Persico AM, Levitt P. A genetic variant that disrupts MET transcription is associated with autism. Proc Natl Acad Sci U S A. 2006 Oct 19.
Department of Pharmacology, Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37203, USA.
There is strong evidence for a genetic predisposition to autism and an intense interest in discovering heritable risk factors that disrupt gene function. Based on neurobiological findings and location within a chromosome 7q31 autism candidate gene region, we analyzed the gene encoding the pleiotropic MET receptor tyrosine kinase in a family based study of autism including 1,231 cases. MET signaling participates in neocortical and cerebellar growth and maturation, immune function, and gastrointestinal repair, consistent with reported medical complications in some children with autism. Here, we show genetic association (P = 0.0005) of a common C allele in the promoter region of the MET gene in 204 autism families. The allelic association at this MET variant was confirmed in a replication sample of 539 autism families (P = 0.001) and in the combined sample (P = 0.000005). Multiplex families, in which more than one child has autism, exhibited the strongest allelic association (P = 0.000007). In case-control analyses, the autism diagnosis relative risk was 2.27 (95% confidence interval: 1.41-3.65; P = 0.0006) for the CC genotype and 1.67 (95% confidence interval: 1.11-2.49; P = 0.012) for the CG genotype compared with the GG genotype. Functional assays showed that the C allele results in a 2-fold decrease in MET promoter activity and altered binding of specific transcription factor complexes. These data implicate reduced MET gene expression in autism susceptibility, providing evidence of a previously undescribed pathophysiological basis for this behaviorally and medically complex disorder.
PMID: 17053076 [PubMed - indexed for MEDLINE]
Chess S, Fernandez P, Korn S. Behavioral consequences of congenital rubella. J Pediatr. 1978 Oct;93(4):699-703.
Psychiatric and behavioral consequences of congenital rubella are reported for 243 children studies during the preschool period, and for 205 of these who were re-examined at ages 8 to 9. At preschool 37% were retarded, with the skew toward severe and profound; 15% had reactive behavior disorder and 7% had autism. At school age retardation diminished to 25%, but neurotic problems and behavioral pathology due to neurologic damage both increased. There were two remissions and three new instances of autism.
PMID: 702254 [PubMed - indexed for MEDLINE]
Comi AM, Zimmerman AW, Frye VH, Law PA, Peeden JN. Familial clustering of autoimmune disorders and evaluation of medical risk factors in autism. J Child Neurol. 1999 Jun;14(6):388-94. Nov;112(5):e420.
Johns Hopkins Hospital, Division of Pediatric Neurology, Baltimore, MD 21212, USA. [email protected]
Autism is an age-dependent neurologic disorder that is often associated with autoimmune disorders in the patients' relatives. To evaluate the frequency of autoimmune disorders, as well as various prenatal and postnatal events in autism, we surveyed the families of 61 autistic patients and 46 healthy controls using questionnaires. The mean number of autoimmune disorders was greater in families with autism; 46% had two or more members with autoimmune disorders. As the number of family members with autoimmune disorders increased from one to three, the risk of autism was greater, with an odds ratio that increased from 1.9 to 5.5, respectively. In mothers and first-degree relatives of autistic children, there were more autoimmune disorders (16% and 21%) as compared to controls (2% and 4%), with odds ratios of 8.8 and 6.0, respectively. The most common autoimmune disorders in both groups were type 1 diabetes, adult rheumatoid arthritis, hypothyroidism, and systemic lupus erythematosus. Forty-six percent of the autism group reported having relatives with rheumatoid diseases, as compared to 26% of the controls. Prenatal maternal urinary tract, upper respiratory, and vaginal infections; asphyxia; prematurity, and seizures were more common in the autistic group, although the differences were not significant. Thirty-nine percent of the controls, but only 11% of the autistic, group, reported allergies. An increased number of autoimmune disorders suggests that in some families with autism, immune dysfunction could interact with various environmental factors to play a role in autism pathogenesis.
PMID: 10385847 [PubMed - indexed for MEDLINE]
Connolly AM, Chez MG, Pestronk A, Arnold ST, Mehta S, Deuel RK. Serum autoantibodies to brain in Landau-Kleffner variant, autism, and other neurologic disorders. J Pediatr. 1999 May;134(5):607-13.
Departments of Neurology and Pediatrics, Washington University, St. Louis Children's Hospital, St Louis, Missouri, USA.
OBJECTIVE: Etiologically unexplained disorders of language and social development have often been reported to improve in patients treated with immune-modulating regimens. Here we determined the frequency of autoantibodies to brain among such children. DESIGN: We collected sera from a cohort of children with (1) pure Landau-Kleffner syndrome (n = 2), (2) Landau-Kleffner syndrome variant (LKSV, n = 11), and (3) autistic spectrum disorder (ASD, n = 11). None had received immune-modulating treatment before the serum sample was obtained. Control sera (n = 71) were from 29 healthy children, 22 with non-neurologic illnesses (NNIs), and 20 children with other neurologic disorders (ONDs). We identified brain autoantibodies by immunostaining of human temporal cortex and antinuclear autoantibodies using commercially available kits. RESULTS: IgG anti-brain autoantibodies were present in 45% of sera from children with LKSV, 27% with ASD, and 10% with ONDs compared with 2% from healthy children and control children with NNIs. IgM autoantibodies were present in 36% of sera from children with ASD, 9% with LKSV, and 15% with ONDs compared with 0% of control sera. Labeling studies identified one antigenic target to be endothelial cells. Antinuclear antibodies with titers >/=1:80 were more common in children with ASD and control children with ONDs. CONCLUSION: Children with LKSV and ASD have a greater frequency of serum antibodies to brain endothelial cells and to nuclei than children with NNIs or healthy children. The presence of these antibodies raises the possibility that autoimmunity plays a role in the pathogenesis of language and social developmental abnormalities in a subset of children with these disorders.
PMID: 10228297 [PubMed - indexed for MEDLINE]
Croen LA, Najjar DV, Ray GT, Lotspeich L, Bernal P. A comparison of health care utilization and costs of children with and without autism spectrum disorders in a large group-model health plan. Pediatrics. 2006 Oct;118(4):e1203-11.
Division of Research, Kaiser Foundation Research Institute, Kaiser Permanente, 2000 Broadway, Oakland, CA 94612, USA. [email protected]
OBJECTIVE: Data on the current costs of medical services for children with autism spectrum disorders are lacking. Our purpose for this study was to compare health care utilization and costs of children with and without autism spectrum disorders in the same health plan. PATIENTS AND METHODS: Participants included all 2- to 18-year-old children with autism spectrum disorders (n = 3053) and a random sample of children without autism spectrum disorders (n = 30529) who were continuously enrolled in the Kaiser Permanente Medical Care Program in northern California between July 1, 2003, and June 30, 2004. Data on health care utilization and costs were derived from health plan administrative databases. MAIN OUTCOME MEASURES: Outcome measures included mean annual utilization and costs of health services per child. RESULTS: Children with autism spectrum disorders had a higher annual mean number of total clinic (5.6 vs 2.8), pediatric (2.3 vs 1.6), and psychiatric (2.2 vs 0.3) outpatient visits. A higher percentage of children with autism spectrum disorders experienced inpatient (3% vs 1%) and outpatient (5% vs 2%) hospitalizations. Children with autism spectrum disorders were nearly 9 times more likely to use psychotherapeutic medications and twice as likely to use gastrointestinal agents than children without autism spectrum disorders. Mean annual member costs for hospitalizations (550 dollars vs 208 dollars), clinic visits (1373 dollars vs 540 dollars), and prescription medications (724 dollars vs 96 dollars) were more than double for children with autism spectrum disorders compared with children without autism spectrum disorders. The mean annual age- and gender-adjusted total cost per member was more than threefold higher for children with autism spectrum disorders (2757 dollars vs 892 dollars). Among the subgroup of children with other psychiatric conditions, total mean annual costs were 45% higher for children with autism spectrum disorders compared with children without autism spectrum disorders; excess costs were largely explained by the increased use of psychotherapeutic medications. CONCLUSIONS: The utilization and costs of health care are substantially higher for children with autism spectrum disorders compared with children without autism spectrum disorders. Research is needed to evaluate the impact of improvements in the management of children with autism spectrum disorders on health care utilization and costs.
PMID: 17015508 [PubMed - indexed for MEDLINE]
Croonenberghs J, Wauters A, Devreese K, Verkerk R, Scharpe S, Bosmans E, Egyed B, Deboutte D, Maes M. Increased serum albumin, gamma globulin, immunoglobulin IgG, and IgG2 and IgG4 in autism. Psychol Med. 2002 Nov;32(8):1457-63.
University Center of Child and Adolescent Psychiatry, A. Z. M. and Department of Medical Biochemistry, University of Antwerp, Wilrijk, Clinical Laboratory A. Z. Middelheim, Antwerp, The Netherlands.
BACKGROUND: Research on the biological pathophysiology of autism has found some evidence that immune alterations may play a role in the pathophysiology of that illness. As a consequence we expected to find that autism is accompanied by abnormalities in the pattern obtained in serum protein electrophoresis and in the serum immunoglobulin (Ig) and IgG subclass profile. METHOD: We examined whether subjects with autism showed changes in total serum protein (TSP) and the serum concentrations of albumin, alpha1 globulin, alpha2 globulin, beta globulin and gamma globulins, IgA, IgM and IgG and the IgG subclasses IgG 1, IgG2, IgG3 and IgG4, compared with normal controls. RESULTS: We found significantly increased concentrations of TSP in autistic subjects, which were attributable to increased serum concentrations of albumin and gamma globulin. Serum IgG, IgG2 and IgG4 were also significantly raised. In autism there were significant and positive correlations between social problems and TSP and serum gamma globulin and between withdrawal symptoms and TSP and serum albumin and IgG. CONCLUSIONS: The results suggest that autism is characterized by increased TSP, a unique pattern obtained in serum protein electrophoresis, i.e. increased serum albumin and IgG, and by a specific IgG subclass profile, i.e. increased serum IgG2 and IgG4. The increased serum concentrations of IgGs in autism may point towards an underlying autoimmune disorder and/or an enhanced susceptibility to infections resulting in chronic viral infections, whereas the IgG subclass skewing may reflect different cytokine-dependent influences on autoimmune B cells and their products.
PMID: 12455944 [PubMed - indexed for MEDLINE]
Dalton P, Deacon R, Blamire A, Pike M, McKinlay I, Stein J, Styles P, Vincent A. Maternal neuronal antibodies associated with autism and a language disorder. Ann Neurol. 2003 Apr;53(4):533-7.
Neurosciences Group, Department of Clinical Neurology, University of Oxford, Oxford, United Kingdom.
Neurodevelopmental disorders could be caused by maternal antibodies or other serum factors. We detected serum antibodies binding to rodent Purkinje cells and other neurons in a mother of three children: the first normal, the second with autism, and the third with a severe specific language disorder. We injected the serum (0.5-1.0 ml/day) into pregnant mice during gestation and found altered exploration and motor coordination and changes in cerebellar magnetic resonance spectroscopy in the mouse offspring, comparing with offspring of mice injected with sera from mothers of healthy children. This evidence supports a role for maternal antibodies in some forms of neurodevelopmental disorder.
PMID: 12666123 [PubMed - indexed for MEDLINE]
DeLong GR, Bean SC, Brown FR 3rd. Acquired reversible autistic syndrome in acute encephalopathic illness in children. Arch Neurol. 1981 Mar;38(3):191-4.
In seeking the neurologic substrate of the autistic syndrome of childhood, previous studies have implicated the medial temporal lobe or the ring of mesolimbic cortex located in the mesial frontal and temporal lobes. During an acute encephalopathic illness, a clinical picture developed in three children that was consistent with infantile autism. This development was reversible. It was differentiated from acquired epileptic aphasia, and the language disorder was differentiated aphasia. One child has rises in serum herpes simplex titers, and a computerized tomographic (CT) scan revealed an extensive lesion of the temporal lobes, predominantly on the left. The other two, with similar clinical syndromes, had normal CT scans, and no etiologic agent was defined. These cases are examples of an acquired and reversible autistic syndrome in childhood, emphasizing the clinical similarities to bilateral medial temporal lobe disease as described in man, including the Klüver-Bucy syndrome seen in postencephalitic as well as postsurgical states.
PMID: 6162440 [PubMed - indexed for MEDLINE]
Denney DR, Frei BW, Gaffney GR. Lymphocyte subsets and interleukin-2 receptors in autistic children. J Autism Dev Disord. 1996 Feb;26(1):87-97.
Department of Psychology, University of Kansas, Lawrence 66045, USA.
Blood samples were obtained from 10 male autistic children ages 7-15 years and 10 age-matched, male, healthy controls. Lymphocyte subsets (helper-inducer, suppressor-cytotoxic, total T, and total B cells) were enumerated using monoclonal antibodies and flow cytometry. Bound and soluble interleukin-2 receptors were assayed in unstimulated blood samples and in cell cultures following 72-hour stimulation with phytohemagglutinin. The children with autism had a lower percentage of helper-inducer cells and a lower helper:suppressor ratio, with both measures inversely related to the severity of autistic symptoms (r = - .56 and - .68, respectively). A lower percentage of lymphocytes expressing bound interleukin-2 receptors following mitogenic stimulation was also noted, and this too was inversely related to the severity of autistic symptoms.
PMID: 8819772 [PubMed - indexed for MEDLINE]
Engstrom HA, Ohlson S, Stubbs EG, Maciulis A, Caldwell V, Odell JD, Torres A.R. Decreased Expression of CD95 (FAS/APO-1) on CD4+ T-lymphocytes from Participants with Autism. J Dev Phys Disabil. 2003 Jun 15;2:155-163(9).
Fallon J. Could one of the most widely prescribed antibiotics amoxicillin/ clavulanate "augmentin" be a risk factor for autism? Med Hypotheses. 2005;64(2):312-5.
Autism is an ever increasing problem in the United States. Characterized by multiple deficits in the areas of communication, development, and behavior; autistic children are found in every community in this country and abroad. Recent findings point to a significant increase in autism which can not be accounted for by means such as misclassification. The state of California recently reported a 273% increase in the number of cases between 1987 and 1998. Many possible causes have been proposed which range from genetics to environment, with a combination of the two most likely. Since the introduction of clavulanate/amoxicillin in the 1980s there has been the increase in numbers of cases of autism. In this study 206 children under the age of three years with autism were screened by means of a detailed case history. A significant commonality was discerned and that being the level of chronic otitis media. These children were found to have a mean number 9.96 bouts of otitis media (with a standard error of the mean of +/-1.83). This represents a sum total for all 206 children of 2052 bouts of otitis media. These children received a mean number of 12.04 courses of antibiotics (standard error of the mean of +/-.125). The sum total number of courses of antibiotics given to all 206 children was 2480. Of those 893 courses were Augmentin. with 362 of these Augmentin courses administered under the age of one year. A proposed mechanism whereby the production of clavulanate may yield high levels of urea/ammonia in the child is presented. Further an examination of this mechanism needs to be undertaken to determine if a subset of children are at risk for neurotoxicity from the use of clavulanic acid in pharmaceutical preparations.
PMID: 15607562 [PubMed - indexed for MEDLINE]
Ferrante P, Saresella M, Guerini FR, Marzorati M, Musetti MC, Cazzullo AG. Significant association of HLA A2-DR11 with CD4 naive decrease in autistic children. Biomed Pharmacother. 2003 Oct;57(8):372-4.
Laboratory of Biology, Don C. Gnocchi Foundation, IRCCS, via Capecelatro 66, 20148 Milan, Italy. [email protected]
Nine autistic children and 37 ethnically homogenous controls were enrolled in the study to assess their human leukocyte antigen (HLA) pattern, and eight healthy children were studied to define their peripheral blood cell subsets. We observed a significant decrease in CD4+ naive and an increase in CD4+ memory T cells in autistic children. These differences were significantly more pronounced in the autistic children bearing the HLA A2 and DR11 alleles. These data support the hypothesis that autism could be due to an immune imbalance occurring in genetically predisposed children.
PMID: 14568232 [PubMed - indexed for MEDLINE]
Fiumara A, Sciotto A, Barone R, D'Asero G, Munda S, Parano E, Pavone L. Peripheral lymphocyte subsets and other immune aspects in Rett syndrome. Pediatr Neurol. 1999 Sep;21(3):619-21.
Department of Paediatric Neurology, Paediatric Clinic, University of Catania, Italy.
A possible role of the immune system in the pathogenesis of some neurologic disorders, including infantile autism, was recently postulated. This observation prompted the authors to investigate some immunologic aspects in a group of patients with Rett syndrome, a disorder still not completely clarified but with some points of commonality with infantile autism. Humoral and cell-mediated immunity were investigated in 20 females with Rett syndrome. Peripheral lymphocyte subsets revealed a reduced percentage of CD8+ suppressor-cytotoxic cells in all of the patients with Rett syndrome, resulting in an increased CD4+/CD8+ ratio. In addition, 15 (75%) of the 20 patients had low levels of natural killer cells. Soluble interleukin-2 receptor was elevated in the youngest patients. Antineuronal and antimyelin ganglioside antibodies were absent, as were antinuclear antibodies, antistriated muscle antibodies, and antismooth muscle antibodies. Immunoglobulin fractions and complement were normal for age in all of the patients.
PMID: 10513687 [PubMed - indexed for MEDLINE]
Furlano RI, Anthony A, Day R, Brown A, McGavery L, Thomson MA, Davies SE, Berelowitz M, Forbes van Gent T, Heijnen CJ, Treffers PD. Autism and the immune system. J Child Psychol Psychiatry. 1997 Mar;38(3):337-49.
Gupta S, Aggarwal S, Rashanravan B, Lee T. Th1- and Th2-like cytokines in CD4+ and CD8+ T cells in autism. J Neuroimmunol. 1998 May 1;85(1):106-9.
Department of Medicine, University of California, Irvine 92697-4075, USA. [email protected]i.edu
Th1-like (IL-2, IFN-gamma) and Th2-like (IL-4, IL-6, and IL-10) cytokines were examined in CD4+ and CD8+ T cells in children with autism. Intracellular cytokines were measured using specific antibodies to various cytokines and anti-CD4 or anti-CD8 monoclonal antibodies by FACScan. Proportions of IFN-gamma+CD4+ T cells and IL-2+CD4+ T cells (Th1), and IFN-gamma+CD8+ and IL-2+CD8+ T cells (TC1) were significantly lower in autistic children as compared to healthy controls. In contrast, IL-4+CD4+ T cells (Th2) and IL-4+CD8+ T cells (TC2) were significantly increased in autism. The proportions of IL-6+ CD4+, IL-6+CD8+ and IL-10+CD4+, IL-10+CD8+ T cells were comparable in autism and control group. These data suggest that an imbalance of Th1- and Th2-like cytokines in autism may play a role in the pathogenesis of autism.
PMID: 9627004 [PubMed - indexed for MEDLINE]
Gurney JG, McPheeters ML, Davis MM. Parental report of health conditions and health care use among children with and without autism: National Survey of Children's Health. Arch Pediatr Adolesc Med. 2006 Aug;160(8):825-30.
Child Health Evaluation and Research Unit, Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109-0456, USA. [email protected]
OBJECTIVE: To compare parent-reported prevalence of health conditions and health care use between children with and without autism. DESIGN: Cross-sectional analysis of the 2003 to 2004 National Survey of Children's Health. SETTING: Population-based sample across the United States. PARTICIPANTS: More than 100 000 parents. The main exposure was "autism" (not further defined), from response to the question: "Has a doctor or health professional ever told you that your child has autism?" MAIN OUTCOME MEASURES: Medical and mental health conditions and measures of health care use. RESULTS: Autism prevalence among children aged 3 to 17 years was 53 per 10 000 (95% confidence interval, 45-61 per 10,000), equating to a national estimate of 324 000 children (95% confidence interval, 274,000-375,000 children). Children with autism had a significantly (P<.001) higher prevalence of depression or anxiety problems (38.9% vs 4.2%) and behavioral or conduct problems (58.9% vs 5.2%) than children without autism. Respiratory, food, and skin allergies were reported by parents more often for children with autism, with food allergies having the strongest relative difference between the groups (odds ratio, 4.5; 95% confidence interval, 3.0-7.0). Children with autism had significantly (P<.001) higher mean physician visits over 12 months for preventive care, nonemergency care, and hospital emergency care, and were far more likely than children without autism to receive physical, occupational, or speech therapy (76.0% vs 6.3%), to need treatment or counseling for an emotional, developmental, or behavioral problem (75.4% vs 7.0%), and, among those taking a prescribed medication, to be using a medication long-term (51.4% vs 14.5%). CONCLUSION: We found markedly higher reports of concurrent conditions and health care use associated with childhood autism in this study.
PMID: 16894082 [PubMed - indexed for MEDLINE]
James SJ, Cutler P, Melnyk S, Jernigan S, Janak L, Gaylor DW, Neubrander JA. Metabolic biomarkers of increased oxidative stress and impaired methylation capacity in children with autism. Am J Clin Nutr. 2004 Dec;80(6):1611-7.
Department of Pediatrics, University of Arkansas for Medical Sciences, and the Arkansas Children's Hospital Research Institute, Little Rock, AR 72202, USA. [email protected]
BACKGROUND: Autism is a complex neurodevelopmental disorder that usually presents in early childhood and that is thought to be influenced by genetic and environmental factors. Although abnormal metabolism of methionine and homocysteine has been associated with other neurologic diseases, these pathways have not been evaluated in persons with autism. OBJECTIVE: The purpose of this study was to evaluate plasma concentrations of metabolites in the methionine transmethylation and transsulfuration pathways in children diagnosed with autism. DESIGN: Plasma concentrations of methionine, S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), adenosine, homocysteine, cystathionine, cysteine, and oxidized and reduced glutathione were measured in 20 children with autism and in 33 control children. On the basis of the abnormal metabolic profile, a targeted nutritional intervention trial with folinic acid, betaine, and methylcobalamin was initiated in a subset of the autistic children. RESULTS: Relative to the control children, the children with autism had significantly lower baseline plasma concentrations of methionine, SAM, homocysteine, cystathionine, cysteine, and total glutathione and significantly higher concentrations of SAH, adenosine, and oxidized glutathione. This metabolic profile is consistent with impaired capacity for methylation (significantly lower ratio of SAM to SAH) and increased oxidative stress (significantly lower redox ratio of reduced glutathione to oxidized glutathione) in children with autism. The intervention trial was effective in normalizing the metabolic imbalance in the autistic children. CONCLUSIONS: An increased vulnerability to oxidative stress and a decreased capacity for methylation may contribute to the development and clinical manifestation of autism.
PMID: 15585776 [PubMed - indexed for MEDLINE]
Jyonouchi H, Geng L, Ruby A, Reddy C, Zimmerman-Bier B. Evaluation of an association between gastrointestinal symptoms and cytokine production against common dietary proteins in children with autism spectrum disorders. J Pediatr. 2005 May;146(5):605-10.
Department of Pediatrics, Division of Pulmonary, Allergy/Immunology, and Infectious Diseases, New Jersey Medical School/UMDNJ, 185 South Orange Avenue, Newark, NJ 07101-1709, USA. [email protected]
OBJECTIVE: To evaluate an association between cytokine production with common dietary proteins as a marker of non-allergic food hypersensitivity (NFH) and gastrointestinal (GI) symptoms in young children with autism spectrum disorders (ASD). STUDY DESIGN: Peripheral blood mononuclear cells (PBMCs) were obtained from 109 ASD children with or without GI symptoms (GI [+] ASD, N = 75 and GI (-) ASD, N = 34], from children with NFH (N = 15), and control subjects (N = 19). Diarrhea and constipation were the major GI symptoms. We measured production of type 1 T-helper cells (Th1), type 2 T-helper cells (Th2), and regulatory cytokines by PBMCs stimulated with whole cow's milk protein (CMP), its major components (casein, beta-lactoglobulin, and alpha-lactoalbumin), gliadin, and soy. RESULTS: PBMCs obtained from GI (+) ASD children produced more tumor necrosis factor-alpha (TNF-alpha)/interleukin-12 (IL-12) than those obtained from control subjects with CMP, beta-lactoglobulin, and alpha-lactoalbumin, irrespective of objective GI symptoms. They also produced more TNF-alpha with gliadin, which was more frequently observed in the group with loose stools. PBMCs obtained from GI (-) ASD children produced more TNF-alpha/IL-12 with CMP than those from control subjects, but not with beta-lactoglobulin, alpha-lactoalbumin, or gliadin. Cytokine production with casein and soy were unremarkable. CONCLUSION: A high prevalence of elevated TNF-alpha/IL-12 production by GI (+) ASD PBMCs with CMP and its major components indicates a role of NFH in GI symptoms observed in children with ASD.
PMID: 15870662 [PubMed - indexed for MEDLINE]
Jyonouchi H, Sun S, Le H. Proinflammatory and regulatory cytokine production associated with innate and adaptive immune responses in children with autism spectrum disorders and developmental regression. J Neuroimmunol. 2001 Nov 1;120(1-2):170-9.
Department of Pediatrics, University of Minnesota, MMC 610 FUMC, 420 Delaware Street SE, Minneapolis, MN 55455, USA. [email protected]
We determined innate and adaptive immune responses in children with developmental regression and autism spectrum disorders (ASD, N=71), developmentally normal siblings (N=23), and controls (N=17). With lipopolysaccharide (LPS), a stimulant for innate immunity, peripheral blood mononuclear cells (PBMCs) from 59/71 (83.1%) ASD patients produced >2 SD above the control mean (CM) values of TNF-alpha, IL-1beta, and/or IL-6 produced by control PBMCs. ASD PBMCs produced higher levels of proinflammatory/counter-regulatory cytokines without stimuli than controls. With stimulants of phytohemagglutinin (PHA), tetanus, IL-12p70, and IL-18, PBMCs from 47.9% to 60% of ASD patients produced >2 SD above the CM values of TNF-alpha depending on stimulants. Our results indicate excessive innate immune responses in a number of ASD children that may be most evident in TNF-alpha production.
PMID: 11694332 [PubMed - indexed for MEDLINE]
Jyonouchi H, Sun S, Itokazu N. Innate immunity associated with inflammatory responses and cytokine production against common dietary proteins in patients with autism spectrum disorder. Neuropsychobiology. 2002;46(2):76-84.
Department of Pediatrics, University of Minnesota, Minneapolis, Minn, USA.
OBJECTIVES: Children with autism spectrum disorder (ASD) frequently reveal various gastrointestinal (GI) symptoms that may resolve with an elimination diet along with apparent improvement of some of the behavioral symptoms. Evidence suggests that ASD may be accompanied by aberrant (inflammatory) innate immune responses. This may predispose ASD children to sensitization to common dietary proteins (DP), leading to GI inflammation and aggravation of some behavioral symptoms. METHODS: We measured IFN-gamma, IL-5, and TNF-alpha production against representative DPs [gliadin, cow's milk protein (CMP), and soy] by peripheral blood mononuclear cells (PBMCs) from ASD and control children [those with DP intolerance (DPI), ASD siblings, and healthy unrelated children]. We evaluated the results in association with proinflammatory and counter-regulatory cytokine production with endotoxin (LPS), a microbial product of intestinal flora and a surrogate stimulant for innate immune responses. RESULTS: ASD PBMCs produced elevated IFN-gamma and TNF-alpha, but not IL-5 with common DPs at high frequency as observed in DPI PBMCs. ASD PBMCs revealed increased proinflammatory cytokine responses with LPS at high frequency with positive correlation between proinflammatory cytokine production with LPS and IFN-gamma and TNF-alpha production against DPs. Such correlation was less evident in DPI PBMCs. CONCLUSION: Immune reactivity to DPs may be associated with apparent DPI and GI inflammation in ASD children that may be partly associated with aberrant innate immune response against endotoxin, a product of the gut bacteria. Copyright 2002 S. Karger AG, Basel
PMID: 12378124 [PubMed - indexed for MEDLINE]
Jyonouchi H, Geng L, Ruby A, Zimmerman-Bier B. Dysregulated innate immune responses in young children with autism spectrum disorders: their relationship to gastrointestinal symptoms and dietary intervention. Neuropsychobiology. 2005;51(2):77-85.
Konstantareas MM, Homatidis S. Ear infections in autistic and normal children. J Autism Dev Disord. 1987 Dec;17(4):585-94.
Clarke Institute of Psychiatry, Toronto, Ontario, Canada.
The frequency of ear infections, ear tube drainage, and deafness was examined through parental reports in autistic and yoke-matched, normal children. For the autistic group these difficulties were additionally examined as a function of the children's cognitive and communication abilities, verbal versus nonverbal status, sex, and degree of autistic symptomatology. Autistic children had a greater incidence of ear infections than matched normal peers. Lower-functioning children had an earlier onset of ear infections than their higher-functioning autistic peers. Ear infections coexisted with low-set ears, and with a higher autistic symptomatology score. The findings are discussed in terms of greater CNS vulnerability in the autistic children, which is likely present since embryogenesis. The possible adverse consequences of intermittent hearing loss on language, cognitive, and socioaffective development are considered.
PMID: 3680158 [PubMed - indexed for MEDLINE]
Korvatska E, Van de Water J, Anders TF, Gershwin ME. Genetic and immunologic considerations in autism. Neurobiol Dis. 2002 Mar;9(2):107-25.
Division of Rheumatology, Allergy, and Clinical Immunology, University of California at Davis, Davis, California 95616, USA.
According to recent epidemiological surveys, autistic spectrum disorders have become recognized as common childhood psychopathologies. These life-lasting conditions demonstrate a strong genetic determinant consistent with a polygenic mode of inheritance for which several autism susceptibility regions have been identified. Parallel evidence of immune abnormalities in autistic patients argues for an implication of the immune system in pathogenesis. This review summarizes advances in the molecular genetics of autism, as well as recently emerging concerns addressing the disease incidence and triggering factors. The neurochemical and immunologic findings are analyzed in the context of a neuroimmune hypothesis for autism. Studies of disorders with established neuroimmune nature indicate multiple pathways of the pathogenesis; herein, we discuss evidence of similar phenomena in autism. (c)2002 Elsevier Science (USA).
PMID: 11895365 [PubMed - indexed for MEDLINE]
Krause I, He XS, Gershwin ME, Shoenfeld Y. Brief report: immune factors in autism: a critical review. J Autism Dev Disord. 2002 Aug;32(4):337-45.
Research Unit of Autoimmune Diseases, Sheba Medical Center, Tel-Hashomer, and the Sackler Faculty of Medicine, Tel-Aviv University, Israel.
Pervasive developmental disorders represent a group of neurodevelopmental disorders that affect children early in their development. Autistic disorder is the best described of these disorders, yet even this term covers a broad group of clinical presentations. Various immune system abnormalities, including autoimmunity and defects in different subsets of immune cells, have been reported in children with autistic disorder, suggesting that immune factors may play a role in the development of autism. Based on anecdotal observation, vaccination was proposed to cause autism in some children, but several controlled studies have failed to support this claim. Intravenous immunoglobulin infusions has been tested as immunotherapy for autism, although the preliminary results are inconclusive and there is a risk of potentially fatal transmission of blood-borne pathogens. To examine this issue, intensive well-controlled epidemiological and bench studies need to be carried out in defined and carefully controlled study subjects to establish the cellular and molecular basis of autism, against which the effects of each proposed immune factor can be examined.
PMID: 12199139 [PubMed - indexed for MEDLINE]
Libbey JE, Sweeten TL, McMahon WM, Fujinami RS. Autistic disorder and viral infections. J Neurovirol. 2005 Feb;11(1):1-10.
Department of Neurology, University of Utah, Salt Lake City, Utah 84132-2305, USA.
Autistic disorder (autism) is a behaviorally defined developmental disorder with a wide range of behaviors. Although the etiology of autism is unknown, data suggest that autism results from multiple etiologies with both genetic and environmental contributions, which may explain the spectrum of behaviors seen in this disorder. One proposed etiology for autism is viral infection very early in development. The mechanism, by which viral infection may lead to autism, be it through direct infection of the central nervous system (CNS), through infection elsewhere in the body acting as a trigger for disease in the CNS, through alteration of the immune response of the mother or offspring, or through a combination of these, is not yet known. Animal models in which early viral infection results in behavioral changes later in life include the influenza virus model in pregnant mice and the Borna disease virus model in newborn Lewis rats. Many studies over the years have presented evidence both for and against the association of autism with various viral infections. The best association to date has been made between congenital rubella and autism; however, members of the herpes virus family may also have a role in autism. Recently, controversy has arisen as to the involvement of measles virus and/or the measles, mumps, rubella (MMR) vaccine in the development of autism. Biological assays lend support to the association between measles virus or MMR and autism whereas epidemiologic studies show no association between MMR and autism. Further research is needed to clarify both the mechanisms whereby viral infection early in development may lead to autism and the possible involvement of the MMR vaccine in the development of autism.
PMID: 15804954 [PubMed - indexed for MEDLINE]
Lopez-Pison J, Rubio-Rubio R, Urena-Hornos T, Omenaca-Teres M, Sans A, Cabrerizo de Diago R, Pena-Segura JL. Retrospective diagnosis of congenital infection by cytomegalovirus in the case of one infant.
Sección de Neuropediatría, Hospital Universitario Miguel Servet, 50009 Zaragoza, España. [email protected]
INTRODUCTION: 10-15% of asymptomatic congenital infections by cytomegalovirus (CMV) in the neonatal period develop persistent problems with varying degrees of severity, fundamentally involving neurological disorders, neurosensory hypoacusis and hypovision, which appear from the age of 6-9 months onwards, when a diagnosis is no longer possible. The PCR (polymerase chain reaction) technique can detect DNA of CMV in blood samples on filter paper used for screening hypothyroidism and metabolic pathologies that were kept from the neonatal period. CASE REPORT: A child aged 3 years and 8 months with delayed intrauterine growth, autism, mental retardation, microcephalus and neurosensory hypoacusis; periventricular calcifications, leukoencephalopathy and bilateral malformation of the temporal lobe; and a diagnosis of congenital CMV confirmed by detection of DNA by PCR in the blood sample on filter paper saved from the neonatal period. CONCLUSIONS: The retrospective study of congenital infection by CMV should be considered when faced with severity and varying association of delayed intrauterine growth, microcephalus, neurosensory hypoacusis, chorioretinitis, mental retardation, autism or other behavioural disorders, intracranial calcifications, encephaloclastic alterations, leukoencephalopathy, cortical dysplasia and malformations of the temporal lobe and the hippocampus. Since the filter papers from neonatal screening are not kept for ever, perhaps the idea of doing so ought to be considered, given the possibilities they offer for retrospective studies.
PMID: 15973639 [PubMed - indexed for MEDLINE]
Lucarelli S, Frediani T, Zingoni AM, Ferruzzi F, Giardini O, Quintieri F, Barbato M, D'Eufemia P, Cardi E. Food allergy and infantile autism. Panminerva Med. 1995 Sep;37(3):137-41.
Department of Paediatrics, University of Rome La Sapienza, Italy.
The etiopathogenesis of infantile autism is still unknown. Recently some authors have suggested that food peptides might be able to determine toxic effects at the level of the central nervous system by interacting with neurotransmitters. In fact a worsening of neurological symptoms has been reported in autistic patients after the consumption of milk and wheat. The aim of the present study has been to verify the efficacy of a cow's milk free diet (or other foods which gave a positive result after a skin test) in 36 autistic patients. We also looked for immunological signs of food allergy in autistic patients on a free choice diet. We noticed a marked improvement in the behavioural symptoms of patients after a period of 8 weeks on an elimination diet and we found high levels of IgA antigen specific antibodies for casein, lactalbumin and beta-lactoglobulin and IgG and IgM for casein. The levels of these antibodies were significantly higher than those of a control group which consisted of 20 healthy children. Our results lead us to hypothesise a relationship between food allergy and infantile autism as has already been suggested for other disturbances of the central nervous system.
PMID: 8869369 [PubMed - indexed for MEDLINE]
Mehler MF, Kessler JA. Cytokines in brain development and function. Adv Protein Chem. 1998;52:223-51.
Department of Neurology, Rose F. Kennedy Center for Research in Mental Retardation and Human Development, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
PMID: 9917922 [PubMed - indexed for MEDLINE]
Meyer U, Nyffeler M, Engler A, Urwyler A, Schedlowski M, Knuesel I, Yee BK, Feldon J. The time of prenatal immune challenge determines the specificity of inflammation-mediated brain and behavioral pathology. J Neurosci. 2006 May 3;26(18):4752-62.
Laboratory of Behavioural Neurobiology, Swiss Federal Institute of Technology Zurich, CH-8603 Schwerzenbach, Switzerland.
Disturbance to early brain development is implicated in several neuropsychiatric disorders including autism, schizophrenia, and mental retardation. Epidemiological studies have indicated that the risk of developing these disorders is enhanced by prenatal maternal infection, presumably as a result of neurodevelopmental defects triggered by cytokine-related inflammatory events. Here, we demonstrate that the effects of maternal immune challenge between middle and late gestation periods in mice are dissociable in terms of fetal brain cytokine responses to maternal inflammation and the pathological consequences in brain and behavior. Specifically, the relative expression of pro- and anti-inflammatory cytokines in the fetal brains in response to maternal immune challenge may be an important determinant among other developmental factors for the precise pathological profile emerging in later life. Thus, the middle and late gestation periods correspond to two windows with differing vulnerability to adult behavioral dysfunction, brain neuropathology in early adolescence, and of the acute cytokine responses in the fetal brain.
PMID: 16672647 [PubMed - indexed for MEDLINE]
Molloy C, Morrow A, Meinzen-Derr J, Schleifer K, Dienger K, Manning-Courtney P, Altaye M, Wills-Karp M. Elevated cytokine levels in children with autism spectrum disorder. J Neuroimmunology. 2006;172:198-205.
Center for Epidemiology and Biostatistics, Cincinnati Children's Hospital Medical Center, and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229-3039, United States. [email protected]
This study compared production of IL-2, IFN-gamma, IL-4, IL-13, IL-5 and IL-10 in peripheral blood mononuclear cells from 20 children with autism spectrum disorder to those from matched controls. Levels of all Th2 cytokines were significantly higher in cases after incubation in media alone, but the IFN-gamma/IL-13 ratio was not significantly different between cases and controls. Cases had significantly higher IL-13/IL-10 and IFN-gamma/IL-10 than controls. Conclusion: Children with ASD had increased activation of both Th2 and Th1 arms of the adaptive immune response, with a Th2 predominance, and without the compensatory increase in the regulatory cytokine IL-10.
PMID: 16360218 [PubMed - indexed for MEDLINE]
Murch SH, Walker-Smith JA. Nutrition in inflammatory bowel disease. Baillieres Clin Gastroenterol. 1998 Dec;12(4):719-38.
University Department of Paediatric Gastroenterology, Royal Free Hospital, London, UK.
Nutrition is clearly disturbed by active intestinal inflammation. Appetite is reduced, yet energy substrates are diverted into the inflammatory process, and thus weight loss is characteristic. The nutritional disturbance represents part of a profound defect of somatic function. Linear growth and pubertal development in children are notably retarded, body composition is altered, and there may be significant psychosocial disturbance. Macrophage products such as tumour necrosis factor-alpha and interleukins-1 and 6 may be the central molecules that link the inflammatory process to this derangement of homeostasis. Intriguingly, there is also increasing evidence that an aggressive nutritional programme may in itself be sufficient to reduce the mucosal inflammatory response. Recent evidence suggests that enteral nutrition alone may reduce many pro-inflammatory cytokines to normal and allow mucosal healing. In addition, specific nutritional components, such as n-3 polyunsaturated fatty acids, may have an anti-inflammatory effect as they may alter the pattern of leukotrienes generated during the immune response. The recent discovery of the specific molecular mediators of appetite and body composition, such as leptin and myostatin, may allow increased therapeutic specificity and further improvement in the nutritional treatment of the inflammatory bowel diseases.
PMID: 10079904 [PubMed - indexed for MEDLINE]
Niehus R, Lord C. Early medical history of children with autism spectrum disorders. J Dev Behav Pediatr. 2006 Apr;27(2 Suppl):S120-7.
University of Michigan Autism and Communication Disorders Center University of Michigan, Ann Arbor, Michigan 48109, USA.
Previous studies have suggested that children with autism spectrum disorders (ASD) may have different medical histories than nonspectrum children in several areas: their reactions to vaccinations, number of ear infections, chronic gastrointestinal problems, and use of antibiotics. Furthermore, some studies have found associations between regressive autism and gastrointestinal (GI) symptoms. The present study analyzes the medical records from birth to the age of 2 years of 99 children (24 typically developing; 75 with ASD, of whom 29 had parent-reported regression). Data were coded in the following areas: frequency and purpose of pediatrician visits, frequency and type of illnesses and medications, type and chronicity of GI complaints, date of vaccinations, growth data, and whether the pediatrician noted behaviors indicative of an ASD before the age of 2 years. Children with ASD were found to have significantly more ear infections than the typically developing children as well as to use significantly more antibiotics. Typically developing children had significantly more illness-related fevers. There was a nonsignificant trend toward the ASD group having more chronic gastrointestinal problems. There were no significant differences between the groups for the age of vaccination or for number of pediatrician visits. Finally, pediatricians noted symptoms of onset of possible autism, including language delay, for 44 of the 75 children with ASD and 2 of the 24 typical children. Results are discussed in terms of needs for future research.
PMID: 16685178 [PubMed - indexed for MEDLINE]
Okada K, Hashimoto K, Iwata Y, Nakamura K, Tsujii M, Tsuchiya KJ, Sekine Y, Suda S, Suzuki K, Sugihara GI, Matsuzaki H, Sugiyama T, Kawai M, Minabe Y Takei N, Mori N. Decreased serum levels of transforming growth factor-beta1 in patients with autism. Prog Neuropsychopharmacol Biol Psychiatry. 2006 Oct 5.
Department of Psychiatry and Neurology, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka 431-3192, Japan.
BACKGROUND: The neurobiological basis for autism remains poorly understood. Given the key role of transforming growth factor-beta1 (TGF-beta1) in brain development, we hypothesized that TGF-beta1 plays a role in the pathophysiology of autism. In this study, we studied whether serum levels of TGF-beta1 are altered in patients with autism. METHODS: We measured serum levels of TGF-beta1 in 19 male adult patients with autism and 21 age-matched male healthy subjects using enzyme-linked immunosorbent assay (ELISA). RESULTS: The serum levels (7.34+/-5.21 ng/mL (mean+/-S.D.)) of TGF-beta1 in the patients with autism were significantly (z=-5.106, p<0.001) lower than those (14.48+/-1.64 ng/mL (mean+/-S.D.)) of normal controls. However, there were no marked or significant correlations between serum TGF-beta1 levels and other clinical variables, including Autism Diagnostic Interview-Revised (ADI-R) scores, Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), aggression, Theory of Mind, and Intellectual Quotient (IQ) in patients. CONCLUSIONS: These findings suggest that decreased levels of TGF-beta1 may be implicated in the pathophysiology of autism.
PMID: 17030376 [PubMed - indexed for MEDLINE]
Pardo CA, Vargas DL, Zimmerman AW. Immunity, neuroglia and neuroinflammation in autism. Int Rev Psychiatry. 2005 Dec;17(6):485-95.
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. [email protected]
Autism is a complex neurodevelopmental disorder of early onset that is highly variable in its clinical presentation. Although the causes of autism in most patients remain unknown, several lines of research support the view that both genetic and environmental factors influence the development of abnormal cortical circuitry that underlies autistic cognitive processes and behaviors. The role of the immune system in the development of autism is controversial. Several studies showing peripheral immune abnormalities support immune hypotheses, however until recently there have been no immune findings in the CNS. We recently demonstrated the presence of neuroglial and innate neuroimmune system activation in brain tissue and cerebrospinal fluid of patients with autism, findings that support the view that neuroimmune abnormalities occur in the brain of autistic patients and may contribute to the diversity of the autistic phenotypes. The role of neuroglial activation and neuroinflammation are still uncertain but could be critical in maintaining, if not also in initiating, some of the CNS abnormalities present in autism. A better understanding of the role of neuroinflammation in the pathogenesis of autism may have important clinical and therapeutic implications.
PMID: 16401547 [PubMed - indexed for MEDLINE]
Pletnikov MV, Jones ML, Rubin SA, Moran TH, Carbone KM. Rat model of autism spectrum disorders. Genetic background effects on Borna disease virus-induced developmental brain damage. Ann N Y Acad Sci. 2001 Jun;939:318-9.
Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
PMID: 11462786 [PubMed - indexed for MEDLINE]
Plioplys AV. Autism: electroencephalogram abnormalities and clinical improvement with valproic acid. Arch Pediatr Adolesc Med. 1994 Feb;148(2):220-2.
Division of Neurology, Mercy Hospital and Medical Center, Chicago, IL 60616.
PMID: 8118547 [PubMed - indexed for MEDLINE]
Plioplys AV, Greaves A. Yoshida W. Anti-CNS antibodies in childhood neurologic diseases. Neuropediatrics. 1989;20:93.
Department of Pediatrics, Hospital for Sick Children, University of Toronto, Ontario, Canada.
To study the incidence of circulating anti-CNS antibodies in childhood neurologic diseases, a population study was undertaken. Serum samples were obtained from a total of 348 children and stored at -80 degrees C until being studied. The samples were collected when routine blood tests were being performed. In all cases informed consent was obtained. This study was approved by hospital ethics review committees. One hundred and ninety-nine of the samples were from children with no known neurologic illnesses and served as the control group. One hundred and twenty-one of the samples were from children with epilepsy and the remaining 28 from a number of different neurologic conditions. The serum samples were screened against normal, adult, autopsy-derived cerebellar and frontal cortex tissue sections and Western blots. Serum immunoreactivity was revealed using HRP-conjugated anti-human IgG. Significant findings included: (1) patients with epilepsy had an increased incidence of anti-CNS reactivity as revealed on frontal cortex immunoblots (p less than 0.05) but not on cerebellar immunoblots; (2) there was an increase in the incidence of immunoblot reactivity with age in the controls and the neurology cases; (3) there was an increased incidence of immunoblot reactivity in those cases with a presumed inflammatory central or peripheral neurologic disease; (4) in six additional cases with opsoclonus-myoclonus there was cerebellar-specific immunoreactivity with identified antigenic molecular weights of 27 and 35, and 62 kDaltons; (5) in 31 additional cases of systemic lupus erythematosus there was significant immunoblot reactivity (p less than 0.001) when compared to a subset of age-matched controls. There was no difference in immunoreactivity between males and females. There was no significant increase in immunoreactivity in those children with cognitive disturbances including developmental delay and mental retardation.
PMID: 2739881 [PubMed - indexed for MEDLINE]
Rumsey JM, Ernst M. Functional neuroimaging of autistic disorders. Ment Retard Dev Disabil Res Rev. 2000;6(3):171-9.
Clinical Neuroscience Branch, National Institute of Mental Health, Bethesda, Maryland 20892, USA. [email protected]
Functional neuroimaging methods hold promise for elucidating the neurobiology of autistic disorders, yet they present difficult practical and scientific challenges when applied to these complex and heterogeneous syndromes. Single-state studies of brain metabolism and blood flow thus far have failed to yield consistent findings, but suggest considerable variability in regional patterns of cerebral synaptic activity. Patients with idiopathic autism are less likely to show abnormalities than are patients with comorbid illness or epilepsy. Activation studies have begun to suggest alterations in brain organization for language and cognition. Neurotransmitter studies using positron emission tomography (PET) suggest abnormalities of serotonergic and dopaminergic function. Studies using magnetic resonance spectroscopy (MRS) have begun to document metabolic deficits in the frontal cortex and cerebellum. A single study using magnetoencephalography suggests a high incidence of epileptiform activity in children with autistic regression. Research needs include well-controlled developmental studies, particularly of young subjects and relatively homogeneous subgroups, which balance scientific rigor with ethical constraints. Investigations of the serotonergic and dopaminergic systems, limbic-based memory and emotional systems, and the role of epileptiform activity in autism represent priorities for future research.
PMID: 10982494 [PubMed - indexed for MEDLINE]
Silva SC, Correia C, Fesel C, Barreto M, Coutinho AM, Marques C, Miguel TS, Ataide A, Bento C, Borges L, Oliveira G, Vicente AM. Autoantibody repertoires to brain tissue in autism nuclear families. J Neuroimmunol. 2004 Jul;152(1-2):176-82.
Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2781-196 Oeiras, Portugal.
The hypothesis of an immune dysfunction in autism spectrum disorders has previously been put forward without, however, compelling evidence of a direct relation to its etiology or pathogenesis. To further understand if autoimmunity could play a significant role in autism, we analyzed autoantibody repertoires to brain tissue extract in the plasma of 171 autism children, their parents, and 54 controls, by quantitative immunoblotting. Multiparametric analysis revealed significant differences between patients and controls, and showed that one single reactivity in Section 32 of the blot had the most power to discriminate between these samples. Family correlation coefficients and heritability estimates did not provide any evidence that this reactivity was genetically determined. While the molecular weight of the target protein suggested that it might be an isoform of Myelin Basic Protein (MBP), inhibition assays with human MBP argued against this hypothesis. The study evidences the widespread occurrence of autoreactivities to brain tissue in autism patients, which may represent the immune system's neuroprotective response to a previous brain injury occurred during neurodevelopment. The molecular identification of the target protein in Section 32 will contribute to the understanding of the role of immune responses against brain antigens in autistic patients.
PMID: 15223250 [PubMed - indexed for MEDLINE]
Singer HS, Morris CM, Williams PN, Yoon DY, Hong JJ, Zimmerman AW. Antibrain antibodies in children with autism and their unaffected siblings. J Neuroimmunol. 2006 Sep;178(1-2):149-155.
Department of Neurology, Johns Hopkins University School of Medicine, Jefferson Street Building 124, 600 N. Wolfe Street, Baltimore, MD 21287-1000, USA. [email protected]
Serum autoantibodies to human brain, identified by ELISA and Western immunoblotting, were evaluated in 29 children with autism spectrum disorder (22 with autistic disorder), 9 non-autistic siblings and 13 controls. More autistic subjects than controls had bands at 100 kDa in caudate, putamen and prefrontal cortex (p<0.01) as well as larger peak heights of bands at 73 kDa in the cerebellum and cingulate gyrus. Both autistic disorder subjects and their matched non-autistic siblings had denser bands (peak height and/or area under the curve) at 73 kDa in the cerebellum and cingulate gyrus than did controls (p<0.01). Results suggest that children with autistic disorder and their siblings exhibit differences compared to controls in autoimmune reactivity to specific epitopes located in distinct brain regions.
PMID: 16842863 [PubMed - indexed for MEDLINE]
Singh VK. Plasma increase of interleukin-12 and interferon-gamma. Pathological significance in autism. J Neuroimmunol. 1996 May;66(1-2):143-5.
Department of Psychiatry, University of Michigan, School of Medicine, Ann Arbor 48109-0656, USA.
Immune factors such as autoimmunity have been implicated in the genesis of autism, a neurodevelopmental disorder. Since autoimmune response involves immune activation, the plasma levels of interferon-alpha (IFN-alpha), interferon-gamma (IFN-gamma), interleukin-12 (IL-12), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and soluble intercellular adhesion molecule-1 (sICAM-1) were measured in autistic patients and age-matched normal controls. The levels of IL-12 and IFN-gamma were significantly (P < or = 0.05) higher in patients as compared to controls. However, IFN-alpha, IL-6, TNF-alpha, and sICAM-1 levels did not significantly differ between the two groups. Because macrophage-derived IL-12 is known to selectively induce IFN-gamma in T helper type-1 (Th-1) cells, it is suggested that IL-12 and IFN-gamma increases may indicate antigenic stimulation of Th-1 cells pathogenetically linked to autoimmunity in autism.
PMID: 8964908 [PubMed - indexed for MEDLINE]
Singh VK. Th1- and Th2-like cytokines in CD4+ and CD8+ T cells in autism. J Neuroimmunol. 1998 May 1;85(1):106-9.
Department of Medicine, University of California, Irvine 92697-4075, USA. [email protected]
Th1-like (IL-2, IFN-gamma) and Th2-like (IL-4, IL-6, and IL-10) cytokines were examined in CD4+ and CD8+ T cells in children with autism. Intracellular cytokines were measured using specific antibodies to various cytokines and anti-CD4 or anti-CD8 monoclonal antibodies by FACScan. Proportions of IFN-gamma+CD4+ T cells and IL-2+CD4+ T cells (Th1), and IFN-gamma+CD8+ and IL-2+CD8+ T cells (TC1) were significantly lower in autistic children as compared to healthy controls. In contrast, IL-4+CD4+ T cells (Th2) and IL-4+CD8+ T cells (TC2) were significantly increased in autism. The proportions of IL-6+ CD4+, IL-6+CD8+ and IL-10+CD4+, IL-10+CD8+ T cells were comparable in autism and control group. These data suggest that an imbalance of Th1- and Th2-like cytokines in autism may play a role in the pathogenesis of autism.
PMID: 9627004 [PubMed - indexed for MEDLINE]
Singh VK, Warren R, Averett R, Ghaziuddin M. Circulating autoantibodies to neuronal and glial filament proteins in autism. Pediatr Neurol. 1997 Jul;17(1):88-90.
Department of Psychiatry, University of Michigan, Ann Arbor 48109-1065, USA.
Autoimmunity may be a pathogenic factor in autism, a behavioral disorder of early childhood onset. Circulating autoantibodies are produced in organ-specific autoimmunity; therefore, we investigated them in the plasma of autistic subjects, mentally retarded (MR) subjects, and healthy controls. Autoantibodies (IgG isotype) to neuron-axon filament protein (anti-NAFP) and glial fibrillary acidic protein (anti-GFAP) were analyzed by the Western immunoblotting technique. We found a significant increase in incidence of anti-NAFP (P = .004) and anti-GFAP (P = .002) in autistic subjects, but not in MR subjects. Clinically, these autoantibodies may be related to autoimmune pathology in autism.
PMID: 9308986 [PubMed - indexed for MEDLINE]
Singh VK, Warren RP, Odell JD, Warren WL, Cole P. Antibodies to myelin basic protein in children with autistic behavior. Brain Behav Immun. 1993 Mar;7(1):97-103.
Biomedical Division, Center for Persons with Disabilities, Logan, Utah.
Based on a possible pathological relationship of autoimmunity to autism, antibodies reactive with myelin basic protein (anti-MBP) were investigated in the sera of autistic children. Using a screening serum dilution of 1:400 in the protein-immunoblotting technique, approximately 58% (19 of 33) sera of autistic children (< or = 10 years of age) were found to be positive for anti-MBP. This result in autistics was significantly (p < or = .0001) different from the controls (8 of 88 or only 9% positive), which included age-matched children with normal health, idiopathic mental retardation (MR) and Down syndrome (DS), and normal adults of 20 to 40 years of age. Since autism is a syndrome of unknown etiology, it is possible that anti-MBP antibodies are associated with the development of autistic behavior.
PMID: 7682457 [PubMed - indexed for MEDLINE]
Singh VK, Singh EA, Warren RP. Hyperserotoninemia and serotonin receptor antibodies in children with autism but not mental retardation. Biol Psychiatry. 1997 Mar 15;41(6):753-5.
Veterans Administration West Los Angeles Medical Center, California 90073.
This study examined the linkage between elevated blood serotonin in autism and the presence of circulating autoantibodies against the serotonin 5HT1A receptor. Information was also obtained on the diagnostic and receptor specificity of these autoantibodies. Blood serotonin was measured as was inhibition of serotonin binding to human cortical membranes by antibody-rich fractions of blood from controls and from patients with childhood autism, schizophrenia, obsessive-compulsive disorder, Tourette's, and multiple sclerosis. The results showed elevated blood serotonin was not closely related to inhibition of serotonin binding by antibody-rich blood fractions. Inhibition of binding was highest for patients with multiple sclerosis and was not specific to the 5HT1A receptor as currently defined. Although inhibition was not specific to autism, the data were insufficient to establish if people with autism differed from normal controls on this measure.
PMID: 1375597 [PubMed - indexed for MEDLINE]
Singh VK, Rivas WH. Prevalence of serum antibodies to caudate nucleus in autistic children. Neurosci Lett. 2004 Jan 23;355(1-2):53-6.
Department of Biology, Biotechnology Center Building, Utah State University, 4700 Old Main Hill, Logan, UT 84322-4700, USA. [email protected]
Autism may involve autoimmunity to brain. We studied regional distribution of antibodies to rat caudate nucleus, cerebral cortex, cerebellum, brain stem and hippocampus. The study included 30 normal and 68 autistic children. Antibodies were assayed by immunoblotting. Autistic children, but not normal children, had antibodies to caudate nucleus (49% positive sera), cerebral cortex (18% positive sera) and cerebellum (9% positive sera). Brain stem and hippocampus were negative. Antibodies to caudate nucleus were directed towards three proteins having 160, 115 and 49 kD molecular weights. Since a significant number of autistic children had antibodies to caudate nucleus, we propose that an autoimmune reaction to this brain region may cause neurological impairments in autistic children. Thus, the caudate nucleus might be involved in the neurobiology of autism.
PMID: 14729233 [PubMed - indexed for MEDLINE]
Stubbs EG, Crawford ML. Depressed lymphocyte responsiveness in autistic children. J Autism Child Schizophr. 1977 Mar;7(1):49-55.
Although there are associations linking autism with prenatal rubella, cytomegalovirus, syphilis, and varicella, the etiology of the autistic state remains obscure. Host defense against the etiologic agents postulated to be responsible for the autism-associated syndromes is believed to be primarily of the cell-mediated type. In this preliminary study, cellular immune function was assessed in vitro by phytohemagglutinin (PHA) stimulation of lymphocyte cultures. Twelve autistic children and 13 control subjects were compared. The autistic group exhibited a depressed lymphocyte transformation response to PHA when compared to the control subjects (p less than .01).
PMID: 139400 [PubMed - indexed for MEDLINE]
Sweeten TL, Bowyer SL, Posey DJ, Halberstadt GM, McDougle CJ. Increased prevalence of familial autoimmunity in probands with pervasive developmental disorders. Pediatrics. 2003 Sweeten TL, Posey DJ, McDougle CJ. High blood monocyte counts and neopterin levels in children with autistic disorder. Am J Psychiatry. 2003 Sep;160(9):1691-3.
Department of Psychiatry, Indiana University School of Medicine, and James Whitcomb Riley Hospital for Children Indianapolis 46202-4800, USA.
OBJECTIVES: Increased prevalence of familial autoimmune disease is a common finding among probands with various autoimmune disorders. Autistic disorder (autism) is a highly genetic disorder with known immune and immunogenetic abnormalities. Previous research has found an increased frequency of autoimmune disorders in families with autistic probands. We further investigated this association by determining the frequency of autoimmune disorders in families that have probands with pervasive developmental disorders (PDDs), including autism, compared with 2 control groups. METHODS: Three well-defined study groups, including 1) families that have a child with a PDD, 2) families that have a child with an autoimmune disorder, and 3) families with a healthy control child, constituted the sample. A questionnaire inquiring about which first- and second-degree family members had received a diagnosis of having specific autoimmune disorders was completed by 101 families in each group. RESULTS: The frequency of autoimmune disorders was significantly higher in families of the PDD probands compared with families of both the autoimmune and healthy control probands. Autoimmunity was highest among the parents of PDD probands compared with parents of the healthy control subjects. Hypothyroidism/Hashimoto's thyroiditis and rheumatic fever were significantly more common in families with PDD probands than in the healthy control families. CONCLUSIONS: Autoimmunity was increased significantly in families with PDD compared with those of healthy and autoimmune control subjects. These preliminary findings warrant additional investigation into immune and autoimmune mechanisms in autism.
PMID: 14595086 [PubMed - indexed for MEDLINE]
Sweeten TL, Posey DJ, McDougle CJ. Brief report: autistic disorder in three children with cytomegalovirus infection. J Autism Dev Disord. 2004 Oct;34(5):583-6.
Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN 46202-4800, USA.
Previous research has identified a relationship between autistic disorder (autism) and specific congenital infections. Three cases of congenital or perinatal cytomegalovirus (CMV) infection occurring in association with autism are described. Hypothetical mechanisms relating congenital infection, such as CMV, to the development of autism are discussed. A better understanding of the immunologic response to certain congenital infections may provide important information pertaining to the pathophysiology and etiology of autism in vulnerable individuals.
PMID: 15628611 [PubMed - indexed for MEDLINE]
Sweeten TL, Posey DJ, Shankar S, McDougle CJ. High nitric oxide production in autistic disorder: a possible role for interferon-gamma. Bio Psychiatry. 2004 Feb 15:55(4):434-7.
Department of Psychiatry, Indiana University School of Medicine, 1111 W. 10th Street, Indianapolis, IN 46202-4800, USA.
BACKGROUND: Neuroimmune regulation abnormalities have been implicated in the pathophysiology of autistic disorder. Nitric oxide (NO) is involved in immune reactivity and is known to affect brain neurodevelopmental processes. Recent evidence indicates that NO, and cytokines involved in NO production, may be high in children with autism. The purpose of this study was to verify that plasma NO is high in children with autism and determine whether this elevation is related to plasma levels of cytokines involved in NO production. METHODS: The metabolites of NO, nitrite, and nitrate (NOx), along with the cytokines interferon-gamma (IFN-gamma), tumor necrosis factor-alpha, and interleukin-1beta, were measured in plasma of 29 children with autism (mean age +/- SD = 6.1 +/- 2.8 years) and 27 age- and gender-matched healthy comparison subjects using commercially available assay kits. RESULTS: Plasma levels of NOx were significantly higher in the autistic subjects (p =.006); plasma levels of the cytokines did not differ between groups. NOx and IFN-gamma levels were positively correlated in the autistic subjects (r =.51; p =.005). CONCLUSIONS: These results confirm that plasma NO is high in some children with autism and suggest that this elevation may be related to IFN-gamma activity.
PMID: 14960298 [PubMed - indexed for MEDLINE]
Swisher CN, Swisher L. Letter: Congenital rubella and autistic behavior. N Engl J Med. 1975 Jul 24;293(4):198.
Swisher CN, Swisher L.
PMID: 1134536 [PubMed - indexed for MEDLINE]
Todd RD, Hickok JM, Anderson GM, Cohen DJ. Antibrain antibodies in infantile autism. Biol Psychiatry. 1988 Mar 15;23(6):644-7.
Todd RD, Hickok JM, Anderson GM, Cohen DJ.
Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110.
PMID: 3355880 [PubMed - indexed for MEDLINE]
Torrente F, Ashwood P, Day R, Machado N, Furlano RI, Anthony A, Davies SE, Wakefield AJ, Thomson MA, Walker-Smith JA, Murch SH. Small intestinal enteropathy with epithelial IgG and complement deposition in children with regressive autism. Mol Psychiatry. 2002;7(4):375-82, 334.
Centre for Paediatric Gastroenterology, Royal Free & University College Medical School, London, UK.
We have reported lymphocytic colitis in children with regressive autism, with epithelial damage prominent. We now compare duodenal biopsies in 25 children with regressive autism to 11 with coeliac disease, five with cerebral palsy and mental retardation and 18 histologically normal controls. Immunohistochemistry was performed for lymphocyte and epithelial lineage and functional markers. We determined the density of intraepithelial and lamina propria lymphocyte populations, and studied mucosal immunoglobulin and complement C1q localisation. Standard histopathology showed increased enterocyte and Paneth cell numbers in the autistic children. Immunohistochemistry demonstrated increased lymphocyte infiltration in both epithelium and lamina propria with upregulated crypt cell proliferation, compared to normal and cerebral palsy controls. Intraepithelial lymphocytes and lamina propria plasma cells were lower than in coeliac disease, but lamina propria T cell populations were higher and crypt proliferation similar. Most strikingly, IgG deposition was seen on the basolateral epithelial surface in 23/25 autistic children, co-localising with complement C1q. This was not seen in the other conditions. These findings demonstrate a novel form of enteropathy in autistic children, in which increases in mucosal lymphocyte density and crypt cell proliferation occur with epithelial IgG deposition. The features are suggestive of an autoimmune lesion.
PMID: 11986981 [PubMed - indexed for MEDLINE]
Trajkovski V, Ajdinski L, Spiroski M. Plasma concentration of immunoglobulin classes and subclasses in children with autism in the Republic of Macedonia: retrospective study. Croat Med J. 2004 Dec;45(6):746-9.
Institute of Immunobiology and Human Genetics, Medical Faculty, PO Box 60, 1109 Skopje, Republic of Macedonia.
AIM: To examine plasma concentration of IgA, IgM, IgG classes, and IgG1, IgG2, IgG3, and IgG4 subclasses in children with autism. METHODS: Infantile autism was diagnosed by the Diagnostic and Statistical Manual for Mental Disorders (DSM)-IV and the International Classification of Diseases (ICD)-10 criteria. Plasma samples were collected from 35 autistic subjects, and their 21 siblings (biological brothers and sisters) who served as healthy controls. Plasma samples were separated by centrifugation and stored at -20 degrees C until the determination. Plasma immunoglobulin classes (IgM, IgA, IgG) and subclasses (IgG1, IgG2, IgG3, IgG4) were determined using a nephelometer. RESULTS: Plasma concentrations (mean+/-standard deviation) of IgM and IgG in autistic children (1.36+/-0.31 g/L and 13.14+/-1.27 g/L, respectively) were significantly higher (p=0.031 and p=0.023, respectively) in comparison with their healthy brothers or sisters (1.20+/-0.15 g/L and 12.39+/-0.96 g/L, respectively). Children with autism had significantly higher plasma concentrations of IgG4 (p<0.001) compared to their siblings (healthy brothers or sisters). Plasma concentration of IgA, IgG1, IgG2, and IgG3 were similar in autistic children and their healthy brothers or sisters. Increased plasma concentration of IgG1 was found (p=0.027) in autistic males (8.06+/-2.40), as compared with their healthy brothers (5.24+/-4.13 g/L). Plasma concentrations of IgG (14.28+/-3.66 g/L), and IgG1 (9.41+/-2.20 g/L) in autistic females were increased (p=0.012 and p=0.021, respectively) in comparison with IgG (11.07+/-2.07) and IgG1 (6.37+/-3.38 g/L) in their healthy sisters. CONCLUSION: Children with autism have increased plasma concentration of immunoglobulines. Increased immunoglobulines in children with autism could be a result of impaired development of the immune system, and/or genetic factors connected with defense mechanism in these children.
PMID: 15578810 [PubMed - indexed for MEDLINE]
Tuchman RF, Rapin I, Shinnar S. Autistic and dysphasic children. I: Clinical characteristics. Pediatrics. 1991 Dec;88(6):1211-8.
Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, New York.
Autism and dysphasia are behaviorally defined disorders of higher cerebral function which in preschool children share the common core symptom of impairment of language. In this study we describe the clinical characteristics of 314 autistic and 237 dysphasic nonautistic children evaluated by one child neurologist. There was no significant difference between autistic and dysphasic children in gestational age, birth weight, or prevalence of associated medical disorders, all of which were infrequent, although a positive history of resuscitation or ventilatory support was more common in dysphasic than autistic children (P = .03). As a group autistic children are more likely than dysphasic children to have language subtypes affecting central processing and formulation, a family history of psychiatric disorders and autism, and a history of regression of language and behavior. After excluding 12 girls with autistic symptoms who met the clinical criteria for Rett syndrome, we found that there was no significant difference in the number of autistic and dysphasic children with an abnormal sensorimotor examination. Girls with autism were more likely than boys to have severe mental deficiency (38% of autistic girls vs 23% of boys) (P = 0.012) and a motor deficit (27% vs 11%) (P = .0009).
PMID: 1956739 [PubMed - indexed for MEDLINE]
Vargas DL, Nascimbene C, Krishnan C, Zimmerman AW, Pardo CA. Neuroglial activation and neuroinflammation in the brain of patients with autism. Ann Neurol. 2005 Jan;57(1)67-81.
Department of Neurology, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA.
Autism is a neurodevelopmental disorder characterized by impaired communication and social interaction and may be accompanied by mental retardation and epilepsy. Its cause remains unknown, despite evidence that genetic, environmental, and immunological factors may play a role in its pathogenesis. To investigate whether immune-mediated mechanisms are involved in the pathogenesis of autism, we used immunocytochemistry, cytokine protein arrays, and enzyme-linked immunosorbent assays to study brain tissues and cerebrospinal fluid (CSF) from autistic patients and determined the magnitude of neuroglial and inflammatory reactions and their cytokine expression profiles. Brain tissues from cerebellum, midfrontal, and cingulate gyrus obtained at autopsy from 11 patients with autism were used for morphological studies. Fresh-frozen tissues available from seven patients and CSF from six living autistic patients were used for cytokine protein profiling. We demonstrate an active neuroinflammatory process in the cerebral cortex, white matter, and notably in cerebellum of autistic patients. Immunocytochemical studies showed marked activation of microglia and astroglia, and cytokine profiling indicated that macrophage chemoattractant protein (MCP)-1 and tumor growth factor-beta1, derived from neuroglia, were the most prevalent cytokines in brain tissues. CSF showed a unique proinflammatory profile of cytokines, including a marked increase in MCP-1. Our findings indicate that innate neuroimmune reactions play a pathogenic role in an undefined proportion of autistic patients, suggesting that future therapies might involve modifying neuroglial responses in the brain.
PMID: 15546155 [PubMed - indexed for MEDLINE]
Vojdani A, Campbell AW, Anyanwu E, Kashanian A, Bock K, Vojdani E. Antibodies to neuron-specific antigens in children with autism: possible cross-reaction with encephalitogenic proteins from milk, Chlamydia pneumoniae and Streptococcus group A. J Neuroimmunol. 2002 Aug;129(1-2):168-77.
Section of Neuroimmunology, Immunosciences Laboratory, Inc., 8693 Wilshire Boulevard, Suite 200, Beverly Hills, CA 90211, USA. [email protected]
We measured autoantibodies against nine different neuron-specific antigens and three cross-reactive peptides in the sera of autistic subjects and healthy controls by means of enzyme-linked immunosorbent assay (ELISA) testing. The antigens were myelin basic protein (MBP), myelin-associated glycoprotein (MAG), ganglioside (GM1), sulfatide (SULF), chondroitin sulfate (CONSO4), myelin oligodendrocyte glycoprotein (MOG), alpha,beta-crystallin (alpha,beta-CRYS), neurofilament proteins (NAFP), tubulin and three cross-reactive peptides, Chlamydia pneumoniae (CPP), streptococcal M protein (STM6P) and milk butyrophilin (BTN). Autistic children showed the highest levels of IgG, IgM and IgA antibodies against all neurologic antigens as well as the three cross-reactive peptides. These antibodies are specific because immune absorption demonstrated that only neuron-specific antigens or their cross-reactive epitopes could significantly reduce antibody levels. These antibodies may have been synthesized as a result of an alteration in the blood-brain barrier. This barrier promotes access of preexisting T-cells and central nervous system antigens to immunocompetent cells, which may start a vicious cycle. These results suggest a mechanism by which bacterial infections and milk antigens may modulate autoimmune responses in autism.
PMID: 12161033 [PubMed - indexed for MEDLINE]
Wakefield AJ, Walker-Smith JA, Murch SH. Colonic CD8 and gamma delta T-cell infiltration with epithelial damage in children with autism. Pediatrics 2001;138:366-72.
University Department of Paediatric Gastroenterology, the Inflammatory Bowel Diseases Study Group, Royal Free and University College School of Medicine, London, United Kingdom.
OBJECTIVES: We have reported colitis with ileal lymphoid nodular hyperplasia (LNH) in children with regressive autism. The aims of this study were to characterize this lesion and determine whether LNH is specific for autism. METHODS: Ileo-colonoscopy was performed in 21 consecutively evaluated children with autistic spectrum disorders and bowel symptoms. Blinded comparison was made with 8 children with histologically normal ileum and colon, 10 developmentally normal children with ileal LNH, 15 with Crohn's disease, and 14 with ulcerative colitis. Immunohistochemistry was performed for cell lineage and functional markers, and histochemistry was performed for glycosaminoglycans and basement membrane thickness. RESULTS: Histology demonstrated lymphocytic colitis in the autistic children, less severe than classical inflammatory bowel disease. However, basement membrane thickness and mucosal gamma delta cell density were significantly increased above those of all other groups including patients with inflammatory bowel disease. CD8(+) density and intraepithelial lymphocyte numbers were higher than those in the Crohn's disease, LNH, and normal control groups; and CD3 and plasma cell density and crypt proliferation were higher than those in normal and LNH control groups. Epithelial, but not lamina propria, glycosaminoglycans were disrupted. However, the epithelium was HLA-DR(-), suggesting a predominantly T(H)2 response. INTERPRETATION: Immunohistochemistry confirms a distinct lymphocytic colitis in autistic spectrum disorders in which the epithelium appears particularly affected. This is consistent with increasing evidence for gut epithelial dysfunction in autism.
PMID: 11241044 [PubMed - indexed for MEDLINE]
Warren RP, Margaretten NC, Pace NC, Foster A. Immune abnormalities in patients with autism. J Autism Dev Disord. 1986 Jun;16(2):189-97.
We have begun an investigation on the immune systems of patients with autism in attempt to determine if immune mechanisms are involved in the development of this severe developmental disorder. A study of 31 autistic patients has revealed several immune-system abnormalities, including reduced responsiveness in the lymphocyte blastogenesis assay to phytohemagglutinin, concanavalin A, and pokeweed mitogen; decreased numbers of T lymphocytes; and an altered ratio of helper to suppressor T cells. Immune-system abnormalities may be directly related to underlying biologic processes of autism, or these changes may be an indirect reflection of the actual pathologic mechanism.
PMID: 2941410 [PubMed - indexed for MEDLINE]
Warren RP, Cole P, Odell JD, Pingree CB, Warren WL, White E, Yonk J, Singh VK. Detection of maternal antibodies in infantile autism. J Am Acad Child Adolesc Psychiatry. 1990 Nov;29(6):873-7.
Developmental Center for Handicapped Persons, Utah State University, Logan 84322.
Maternal antibodies reactive with antigenic proteins expressed on the cell surface of paternal lymphocytes can be detected in couples with histories of more than one miscarriage or stillbirth. It is possible, but not proven, that these antibodies also react with tissues of the fetus and result in fetal death. Since many mothers of autistic children have a history of pregnancy disorder, antibodies were studied in 11 mothers of autistic children who were 6 years of age or younger. Six of the mothers had antibodies that reacted with lymphocytes of the autistic child. Five of these six mothers had a history of pregnancy disorder. Since antigens expressed on lymphocytes are found on cells of the central nervous system and, perhaps, other tissues of the developing embryo, it is suggested that aberrant maternal immunity may be associated with the development of some cases of infantile autism.
PMID: 2273013 [PubMed - indexed for MEDLINE]
Warren RP, Foster A, Margaretten NC. Reduced natural killer cell activity in autism. J Am Acad Child Adolesc Psychiatry. 1987 May;26(3):333-5.
Warren RP, Foster A, Margaretten NC.
PMID: 3597287 [PubMed - indexed for MEDLINE]
Warren RP, Singh VK, Averett RE, Odell JD, Maciulis A, Burger RA, Daniels WW, Warren WL. Immunogenetic studies in autism and related disorders. Mol Chem Neuropathol. 1996 May-Aug;28(1-3):77-81.
Utah State University, Logan 84322, USA.
The major histocompatibility complex comprises a number of genes that control the function and regulation of the immune system. One of these genes, the C4B gene, encodes a product that is involved in eliminating pathogens such as viruses and bacteria from the body. We previously reported that a deficient form of the C4B gene, termed the C4B null allele (no C4B protein produced) had an increased frequently in autism. In this study we attempted to confirm the increased incidence of the C4B null allele in autism and investigated the presence of a C4B null allele in two other childhood disorders, attention-deficit hyperactivity disorder and dyslexia (reading disability). In addition, we explored the relationship of autism to the DR beta 1 gene, a gene located close to the C4B in autism. We confirmed the finding of an increased frequency of the C4B null allele in autism and found that the related disorders also had an increased frequency of this null allele. In addition, two alleles of the DR beta 1 gene also had significantly increased representation in the autistic subjects.
PMID: 8871944 [PubMed - indexed for MEDLINE]
Yonk LJ, Warren RP, Burger RA, Cole P, Odell JD, Warren WL, White E, Singh VK. CD4+ helper T cell depression in autism. Immunol Lett. 1990 Sep;25(4):341-5.
Developmental Center for Handicapped Persons, Utah State University, Logan 84322-6800.
CD4+ (helper) T cells are a heterogenous population of lymphocytes including at least two distinct subpopulations. To investigate the possibility that immune abnormalities in some subjects with autism may involve abnormal distributions of CD4+ and/or CD8+ cells, (suppressor) T cells, peripheral blood lymphocytes of 25 autistic subjects were characterized with monoclonal antibodies and flow cytometry. The autistic subjects had a significantly lower percentage and number of CD4+ cells, a lower number of T cells (CD2+ cells) and B cells (CD20+ cells), and a lower percentage and number of total lymphocytes than siblings and normal subjects. The level of blood values for female subjects appeared lower than those for males as compared to normal subjects of the same sex. These results suggest that a decrease in CD4+ cells is associated with autism.
PMID: 1979061 [PubMed - indexed for MEDLINE]
Zimmerman AW, Connors SL, Matteson KJ, Lee LC, Singer HS, Castaneda JA, Pearce DA. Maternal antibrain antibodies in autism. Brain Behav Immun. 2006 Oct 5.
Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, 707 North Broadway, Baltimore, MD 21205, USA. [email protected]
Autism is a neurodevelopmental disorder of prenatal onset that is behaviorally defined. There is increasing evidence for systemic and neuroimmune mechanisms in children with autism. Although genetic factors are important, atypical prenatal maternal immune responses may also be linked to the pathogenesis of autism. We tested serum reactivity in 11 mothers and their autistic children, maternal controls, and several groups of control children, to prenatal, postnatal, and adult rat brain proteins, by immunoblotting. Similar patterns of reactivity to prenatal (gestational day 18), but not postnatal (day 8) or adult rat brain proteins were identified in autistic children, their mothers, and children with other neurodevelopmental disorders, and differed from mothers of normal children, normal siblings of children with autism and normal child controls. Specific patterns of antibody reactivity were present in sera from the autism mothers, from 2 to 18 years after the birth of their affected children and were unrelated to birth order. Immunoblotting using specific antigens for myelin basic protein (MBP) and glial acidic fibrillary protein (GFAP) suggests that these proteins were not targets of the maternal antibodies. The identification of specific serum antibodies in mothers of children with autism that recognize prenatally expressed brain antigens suggests that these autoantibodies could cross the placenta and alter fetal brain development.
PMID: 17029701 [PubMed - indexed for MEDLINE]
Zimmerman AW, Jyonouchi H, Comi AM, Connors SL, Milstien S, Varsou A, Heyes MP. Cerebrospinal fluid and serum markers of inflammation in autism. Pediatr Neurol. 2005 Sep;33(3):195-201.
Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore Maryland 21205, USA.
Systemic immune abnormalities have no known relevance to brain dysfunction in autism. In order to find evidence for neuroinflammation, we compared levels of sensitive indicators of immune activation: quinolinic acid, neopterin, and biopterin, as well as multiple cytokines and cytokine receptors, in cerebrospinal fluid and serum from children with autism, to control subjects with other neurologic disorders. In cerebrospinal fluid from 12 children with autism, quinolinic acid (P = 0.037) and neopterin (P = 0.003) were decreased, and biopterin (P = 0.040) was elevated, compared with control subjects. In sera from 35 persons with autism, among cytokines, only tumor necrosis factor receptor II was elevated compared with controls (P < 0.02). Decreased quinolinic acid and neopterin in cerebrospinal fluid are paradoxical and suggest dysmaturation of metabolic pathways and absence of concurrent infection, respectively, in autism. Alternatively, they may be produced by microglia but remain localized and not expressed in cerebrospinal fluid.
PMID: 16139734 [PubMed - indexed for MEDLINE]
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