Microglial Morphology and Population Density in Autism Spectrum Disorder Superficial Temporal Cortical Tissue

Abstract

Autism Spectrum Disorder (ASD) is prevalent in an estimated 1% of the global population and is characterized by abnormal neural connectivity and increased immunological anomalies (Lai et al., 2014). It remains unclear whether abnormal connectivity of cortical neurons is directly associated with inflammatory activity in the ASD brain. This study analyzed microglia, a specialized glial cell that functions as the central nervous system's main immune cell. Inflammatory microglia may contribute to neurological changes observed in ASD. We examined microglia density in superficial cortical layers (II/III) of human post-mortem ASD temporal lobe using Nissl and evaluate microglial cell body morphology for signs of inflammation. Our results found an increased density of microglia in ASD versus neurotypical tissue as well as the increased average size of microglia cell bodies in ASD temporal cortex. These results support the idea that in ASD subjects' temporal cortex there is evidence of glial immune system activation.