Brief Report: Low Rates of Herpesvirus Detection in Blood of Individuals with Autism Spectrum Disorder and Controls.

Previous research indicates that infection, especially from viruses in the family Herpesviridae, may play a role in the etiology of some cases of autism spectrum disorder (ASD). Using a case-control design and the polymerase chain reaction with site-specific primers, we screened newborn and childhood blood samples for the presence of eight human herpesviruses. Herpesvirus DNA was detected in 4 of 225 ASD individuals and 2 of 235 controls, with the most frequently detected virus being HHV-6B.

Common Genetic Variants Found in HLA and KIR Immune Genes in Autism Spectrum Disorder.

The "common variant-common disease" hypothesis was proposed to explain diseases with strong inheritance. This model suggests that a genetic disease is the result of the combination of several common genetic variants. Common genetic variants are described as a 5% frequency differential between diseased vs.

Prenatal and Newborn Immunoglobulin Levels from Mother-Child Pairs and Risk of Autism Spectrum Disorders.

Background: An etiological role for immune factors operating during early brain development in children with autism spectrum disorders (ASD) has not yet been established. A major obstacle has been the lack of early biologic specimens that can be linked to later diagnosis. In a prior study, we found lower risk of ASD associated with higher levels of maternally-derived total IgG and Toxoplasmosis gondii (Toxo) IgG in newborn blood spot specimens from children later diagnosed with ASD compared to population controls.

C4B null alleles are not associated with genetic polymorphisms in the adjacent gene CYP21A2 in autism.

Background: Research indicates that the etiology of autism has a strong genetic component, yet so far the search for genes that contribute to the disorder, including several whole genome scans, has led to few consistent findings. However, three studies indicate that the complement C4B gene null allele (i.e.

Are there altered antibody responses to measles, mumps, or rubella viruses in autism?

The role that virus infections play in autism is not known. Others have reported that antibodies against measles virus are higher in the sera/plasma of children with autism versus controls. The authors investigated antibody titers to measles, mumps, and rubella viruses and diphtheria toxoid in children with autism, both classic onset (33) and regressive onset (26) forms, controls (25, healthy age- and gender-matched) and individuals with Tourette's syndrome (24) via enzyme-linked immunosorbent assays.

Are there enhanced MBP autoantibodies in autism?

Autoantibodies to central nervous system antigens, such as myelin basic protein (MBP), may play a role in autism. We measured autoantibody titers to MBP in children with autism, both classic onset and regressive onset forms, controls (healthy age- and gender-matched) and individuals with Tourette syndrome via enzyme-linked immunosorbent assays. We found a significant difference in autoantibody titers to MBP, not accounted for by age or medication, between Tourette and classic autism (both significantly lower) when compared to regressive autism, but not when compared to controls.

How relevant are GFAP autoantibodies in autism and Tourette Syndrome?

Controversy exists over the role of autoantibodies to central nervous system antigens in autism and Tourette Syndrome. We investigated plasma autoantibody titers to glial fibrillary acidic protein (GFAP) in children with classic onset (33) and regressive onset (26) autism, controls (25, healthy age- and gender-matched) and individuals with Tourette Syndrome (24) by enzyme-linked immunosorbent assays. We found a significant difference in autoantibody titers to GFAP, not accounted for by age, between the Tourette (significantly lower) and regressive autism groups.

The association and linkage of the HLA-A2 class I allele with autism.

Previous research has revealed associations between autism and immune genes located in the human leukocyte antigen (HLA). To better understand which HLA genetic loci may be associated with autism, we compared the class I HLA-A and -B alleles in autistic probands with case control subjects from Caucasian families. The frequency of HLA-A2 alleles was significantly increased in autistic subjects compared with normal allelic frequencies from the National Marrow Donors Program (NMDP) (p = 0.

Hyperserotoninemia and altered immunity in autism.

One of the most consistent biological findings in autism is elevated whole blood serotonin (5-HT) levels found in about 1/3 of cases. Immune abnormalities are also commonly observed in this disorder. Given 5-HT's role as an immunomodulator, possible connections between 5-HT and immune abnormalities in autism are explored in this review.

Autistic disorder and viral infections.

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.

Brief report: autistic disorder in three children with cytomegalovirus infection.

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 pilot study of D-cycloserine in subjects with autistic disorder.

Objective: The authors assessed the effects of D-cycloserine on the core symptom of social impairment in subjects with autism.

Method: Following a 2-week, single-blind placebo lead-in phase, drug-free subjects with autistic disorder were administered three different doses of D-cycloserine during each of three 2-week periods. Measures used for subject ratings included the Clinical Global Impression (CGI) scale and Aberrant Behavior Checklist.

High nitric oxide production in autistic disorder: a possible role for interferon-gamma.

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.

Increased prevalence of familial autoimmunity in probands with pervasive developmental disorders.

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.

High blood monocyte counts and neopterin levels in children with autistic disorder.

Objective: Leukocyte counts and plasma neopterin levels were determined in autistic children and matched healthy comparison subjects.

Method: Blood from 31 autistic children and 28 age- and gender-matched healthy comparison subjects was analyzed for numbers of neutrophils, eosinophils, basophils, lymphocytes, monocytes, and total leukocytes and for plasma neopterin levels.

Results: The monocyte count and neopterin level were significantly higher in the autistic children than in the comparison subjects.

The amygdala and related structures in the pathophysiology of autism.

Autism is a neurodevelopmental disorder that is defined behaviorally by severe deficiencies in reciprocal social interaction, verbal and nonverbal communication, and restricted interests. The amygdala is involved in the regulation of social behaviors and may be an important site of pathology for the social dysfunction seen in autism. This review focuses on lesion, postmortem, and neuroimaging studies that investigate the amygdala and related structures in this disorder.