Figure 2.

Regulation of immune responses by IL-10 family cytokines during Mycobacteria infection: IL-10 family of cytokines induced by mycobacteria infection modulates immune responses. IL-10 can enhance intracellular survival and growth of bacilli by inhibition nitric oxide production, phagosomal maturation and IFN-γ-mediating killing. In addition, IL-10 can inhibit CD4+ T cell responses by suppression of IL-12 production and trafficking of Mtb peptide-MHC-II complexes to the plasma membrane. It also suppresses T cells cross-priming by antigen-presenting cells via blocking macrophages apoptosis. IL-10 can modulate granuloma formation via inhibition of TNF-α, Th17 cells and T cells expansion. Il-26 enhances intracellular survival of Mtb by unknown mechanism. IL-26 can recruit neutrophils to site of battle that can cause tissue damage and suppression Th1 response. IL-26 also promotes binding of released bacterial DNA to the TLR9 in surface of plasmacytoid DC resulting in production type I IFN. IL-22 can inhibit intracellular growth of bacilli via enhancing phagolysosomal fusion. IL-22 is an important activator of adaptive immune responses through promoting the expansion of memory CD4+ cells and IFN-γ production and recruitment of B cells to site of infection. IL-24 induces IFN-γ production by CD8+ cells and suppresses FOXP3 T reg cells.