Since TLR4 is an innate immune receptor for bacterial glycoproteins and a major activator of the M1 macrophage phenotype [58], our findings are consistent with high levels of macrophage-derived cytokines in patient blood [5, 39–42], and with other studies finding increased TLR4 mRNA in peripheral mononuclear cells extracted from people with schizophrenia [19, 20]. This evidence concerns the gene TLR4 and schizophrenia.