BackgroundAutism is a common neurodevelopmental syndrome. Numerous rare genetic etiologies are reported; most cases are idiopathic.Methodology/Principal FindingsTo uncover important gene dysregulation in autism we analyzed carefully selected idiopathic autistic and control cerebellar and BA19 (occipital) brain tissues using high resolution whole genome gene expression and whole genome DNA methylation microarrays. No changes in DNA methylation were identified in autistic brain but gene expression abnormalities in two areas of metabolism were apparent: down-regulation of genes of mitochondrial oxidative phosphorylation and of protein translation. We also found associations between specific behavioral domains of autism and specific brain gene expression modules related to myelin/myelination, inflammation/immune response and purinergic signaling.Conclusions/SignificanceThis work highlights two largely unrecognized molecular pathophysiological themes in autism and suggests differing molecular bases for autism behavioral endophenotypes.

SUMMARYObjective: Psychogenic nonepileptic seizures (PNES) in youth are symptoms of a difficult to diagnose and treat conversion disorder. PNES is associated with high medical and psychiatric morbidity, but specific PNES risk factors in the pediatric population are not known. We examined if youth with PNES have a distinct biopsychosocial risk factor profile compared to their siblings and if the interrelationships between these risk factors differentiate the PNES probands from the sibling group. Methods: This multisite study included 55 youth with a confirmed diagnosis of PNES (age range 8.6-18.4 years) and their 35 sibling controls (age range 8.6-18.1 years). A video EEG and psychiatric assessment confirmed the PNES diagnosis. Parents reported on each child's past and present medical/epilepsy, psychiatric, family, and educational history. Each child underwent a structured psychiatric interview, standardized cognitive and academic achievement testing, and completed self-report coping, daily stress, adversities, and parental bonding questionnaires. Results: Compared to their siblings, the PNES probands had significantly more lifetime comorbid medical, neurological (including epilepsy), and psychiatric problems; used more medications and intensive medical services; had more higher anxiety sensitivity, practiced solitary emotional coping, and experienced more lifetime adversities. A principal components analysis of these variables identified a somatopsychiatric, adversity, epilepsy, and cognitive component. The somatopsychiatric and adversity components differentiated the probands from the siblings, and were highly significant predictors of PNES with odds ratios of 15.1 (95% CI [3.4, 67.3], and 9.5 (95% CI [2.0, 45.7]), respectively. The epilepsy and cognitive components did not differentiate between the PNES and sibling groups. Significance: These findings highlight the complex biopsychosocial and distinct vulnerability profile of pediatric PNES. They also underscore the need for screening the interrelated risk factors included in the somatopsychiatric and adversity components and subsequent mental health referral for confirmation of the diagnosis and treatment of youth with PNES.

S100B is a reporter of blood-brain barrier (BBB) integrity which appears in blood when the BBB is breached. Circulating S100B derives from either extracranial sources or release into circulation by normal fluctuations in BBB integrity or pathologic BBB disruption (BBBD). Elevated S100B matches the clinical presence of indices of BBBD (gadolinium enhancement or albumin coefficient). After repeated sub-concussive episodes, serum S100B triggers an antigen-driven production of anti-S100B autoantibodies. We tested the hypothesis that the presence of S100B in extracranial tissue is due to peripheral cellular uptake of serum S100B by antigen presenting cells, which may induce the production of auto antibodies against S100B. To test this hypothesis, we used animal models of seizures, enrolled patients undergoing repeated BBBD, and collected serum samples from epileptic patients. We employed a broad array of techniques, including immunohistochemistry, RNA analysis, tracer injection and serum analysis. mRNA for S100B was segregated to barrier organs (testis, kidney and brain) but S100B protein was detected in immunocompetent cells in spleen, thymus and lymph nodes, in resident immune cells (Langerhans, satellite cells in heart muscle, etc.) and BBB endothelium. Uptake of labeled S100B by rat spleen CD4+ or CD8+ and CD86+ dendritic cells was exacerbated by pilocarpine-induced status epilepticus which is accompanied by BBBD. Clinical seizures were preceded by a surge of serum S100B. In patients undergoing repeated therapeutic BBBD, an autoimmune response against S100B was measured. In addition to its role in the central nervous system and its diagnostic value as a BBBD reporter, S100B may integrate blood-brain barrier disruption to the control of systemic immunity by a mechanism involving the activation of immune cells. We propose a scenario where extravasated S100B may trigger a pathologic autoimmune reaction linking systemic and CNS immune responses.

BackgroundStudies have shown that patients suffering from depression or schizophrenia often have immunological alterations that can be detected in the blood. Others reported a possible link between inflammation, a microgliosis and the blood-brain barrier (BBB) in suicidal patients. Serum S100B is a marker of BBB function commonly used to study cerebrovascular wall function.MethodsWe measured levels of S100B in serum of 40 adolescents with acute psychosis, 24 adolescents with mood disorders and 20 healthy controls. Patients were diagnosed according to DSM-IV TR criteria. We evaluated suicidal ideation using the suicidality subscale of the Brief Psychiatric Rating Scale for Children (BPRS-C).ResultsSerum S100B levels were significantly higher (p<0.05) and correlated to severity of suicidal ideation in patients with psychosis or mood disorders, independent of psychiatric diagnosis. Patients with a BPRS-C suicidality subscores of 1–4 (low suicidality) had mean serum S100B values +/− SEM of 0.152+/−0.020 ng/mL (n = 34) compared to those with BPRS-C suicidality subscores of 5–7 (high suicidality) with a mean of 0.354+/−0.044 ng/mL (n = 30). This difference was statistically significant (p<0.05).ConclusionOur data support the use of S100B as an adjunctive biomarker to assess suicidal risk in patients with mood disorders or schizophrenia.