分子免疫学-T细胞免疫应答机制 2014硕士.ppt

Effector functions of Th1 cells T cell signals that activate macrophages IFN-? CD40L-CD40 interactions Central role of Th1 in the activation of macrophage IFN-? The major sources: Th1, CD8+ T cells The major macrophage-activating cytokine Stimulates the microbicidal activities of phagocytes Stimulates the production of IgG Abs to promote the phagocytosis of microbes CD40L/CD40 Deliver contact-mediated signals activates the transcription factors nuclear factor KB (NF-KB) and activation protein-1 (AP-1) Increases the response to IFN-? Clinical evidence Humans with inherited mutations in CD40L (X-linked hyper-IgM syndrome) : severe deficiencies in CMI to intracellular microbes The effector functions of activated macrophages Killing of phagocytosed microbes Become the more efficient APCs Stimulation of acute inflammation Tissue Repair Activation and functions of macrophages in CMI Th2-Mediated Immune Responses The physiological role of Th2 cells Elimination of helminthic infection Pathological roles of Th2 cell The underlying cause of allergic reactions Effector functions of Th2 cells Promotion of antigen-specific IgE production Activation of eosinophils and mast cells Alternative macrophage activation Barrier immunity by Th2 cytokine Effector functions of Th2 cells The effector function of Th2 cytokines IL-4 and IL-13 Stimulate the production of antigen-specific IgE Alternatively activate macrophages IL-4 promotes expulsion of microbes while IL-13 stimulates mucus secretion IL-5 Recruit and activate eosinophils The orchestration of macrophage activation and polarization by Th cells Biswas S, et al. Nature Immunol, 2010 The physiological role of Th17 cells Protection against extracellular bacterial and fungal infections Pathological roles of Th17 cell may be important in meditating tissue damage in immune-mediated inflammatory diseases, e.g. autoimmune dis