IFNG and infection: Higher serum levels of IFN-γ that promoted M1 polarization and inhibited M2 polarization were observed in TLR2 KO mice compared with WT mice at 4 weeks post-infection (S2 Fig), thus type I immunity may help to downregulate the expression of RELMa. More importantly, IL-6 can recruit both neutrophils and monocytes during inflammation [39].