STAT1 and HIV-1 infection: More importantly, IFN-α and IFN-β neutralizing antibodies, which were able to block the binding of type I IFNs with their receptor IFNR and the downstream STAT1 phosphorylation (60% reduction, [25], Fig. 5H), significantly attenuated both mRNA (Fig. 5G) and protein levels (Fig. 5H and I) of GAC induced by HIV-1 infection.