CXCL8 and schizophrenia: Two studies reported no difference in IL-1β mRNA in the prefrontal cortex,86, 136 despite measuring increases IL-1RA,136 IL-6 (ref. 86) and IL-8 mRNA.86 IFN-γ, measured by enzyme-linked immunosorbent assay, was reported to be increased in the prefrontal cortex of 35 schizophrenia patients compared to unaffected controls.137 However, Rao et al. reported 150% and 3.9 fold increases in IL-1β protein and mRNA respectively in the frontal cortex of schizophrenics.