PPIB and autism: Adults with autism have been shown to have higher proportions of B-lymphocytes when compared to healthy controls [14]. B-lymphocytes specific to certain infections, are also found to be more common among those with autism spectrum disorder, are predictive of the diagnosis, and have been correlated to the severity of repetitive behaviors in autism spectrum disorder [15]. Consistent with this, B-lymphocyte cytokines are elevated in individuals with autism spectrum disorder regardless of immune status [16].