Decreased levels of total immunoglobulin in children with autism are not a result of B cell dysfunction.

Autism spectrum disorders are a heterogeneous group of behaviorally defined disorders having complex etiologies. We previously reported a direct correlation between lower plasma levels of the immunoglobulins (Ig) IgG and IgM and increased severity of behavioral symptoms in children with autism. Our current objective was to determine if these reduced plasma levels of IgG and IgM are the result of defective B cell development, activation, or function. Results suggest no differences in the B cell parameters measured, indicating that decreased Ig in autism is not a result of B cell dysfunction and other immune cells might be involved.