IFNG and listeriosis: Blockage of STAT1 Ser phosphorylation, using STAT1 Ser mutants, significantly altered the IFNγ transcriptional response and its ability to clear Listeria monocytogenes infection, highlighting the relevance of STAT1 Ser phosphorylation in modulating IFNγ response in macrophages (Varinou et al., 2003).