Contrasting studies are reported on the induction of IL-10 and IFN-γ via chitin microparticles (CMPs) during immune stimulation. Our previous studies have shown marked protection among CMP treated Leishmania-infected mice via regulated IL-10/IFN-γ response, at the present study, once more, examined the inconsistent responses regarding the immunologic response of CMPS. To verify whether CMPs could indeed up-regulate IL-10/IFN-γ axis, isolated spleen cells from the myelin oligodendrocyte glycoprotein (MOG) induced experimental autoimmune encephalomyelitis (EAE) mice were cultured in the presence of MOG peptide and/or CMPs. The effects of CMPs on IL-10, IFN-γ and IL-17 production were evaluated by Enzyme-linked Immunosorbent Assay (ELISA). Moreover, GATA binding protein 3 (Gata3), T-box transcription factor TBX21 (Tbx21), and RAR-related orphan receptor gamma (RORγT) expressions (real-time PCR) were investigated. MOG alone stimulated the production of IFN-γ (p≤0.004) but not, IL-10 (p≤0.140). MOG/chitin stimulation resulted in a significant increase in IFN-γ and IL-10 levels, respectively; (p≤0.004 and p≤0.003) rather than MOG. Additionally, the expression of Tbx21 (p≤0.001), but not Gata3 (p≤0.08), was increased in the MOG/chitin-treated spleen cells. All in all, CMP supports Gata3 independent IL-10 production and promotes Tbx21 dependent IFN-γ induction. These results, alongside our previous data, indicate that CMPs has particular adjuvant effects.
Keywords: Chitin; Cytokine; Experimental autoimmune encephalomyelitis; Immunomodulation; Transcription factor.