The Effects And Mechanisms Of CD40 Signal And IL-2R/IL-2 On The Human Monocyte Derived Dendritic Cells In Vitro

Dendritic cells (DC) are professional APC that are specialized for the initiation and regulation of T cell immunity, especially the potent antitumor immunity. Now, DC vaccines has been applied to treat tumor in many clinic trials of immunotherapy. IL-2 is a cytokine which is able to sustain the growth of T, B and natural killer (NK) cells and, during the late phases of antigen specific T-cell response, it contributes to the maintenance of T-cell homeostasis by promoting activation-induced cell death (AICD) of effector T lymphocytes. Recombinant IL-2 demonstrated a value regent in clinic therapy. The effect of IL-2 on human monocyte-derived DC still need to be illustrated.In this study, we investigated the distinct expression profile of CD25 on CD40 and TNF-a activated Mo-DC, and determinate whether CD40 activated DC do express functional IL-2 receptor. Basing on above, we demonstrated the role of IL-2/IL-2R in differentiation, maturation and function of Mo-DC, which could provide value data in preparing DC vaccine.Part I : CD40 signal induced Mo-DC expression of IL-2R/IL-2 and the related biological effectsObjects: compare the roles of CD40mAb or TNF-a induced CD25 (IL-2Ra) expressionon Mo-DC in vitro, study on highly avidity IL-2R expressed on Mo-DC surface, roles ofIL-2 on Mo-DC generation and functions.Methods: using GM-CSF, IL-4 to induce Mo-DC as usual, CD40 or TNF-a was addedinto mature DC; FACS analyzed Mo-DC phenotypes; westernblotting detected Mo-DCNF-kB; confocal microscope and immunoprecipitation detected highly avidity IL-2Rexpression; cytohistochemistry detected IL-2; ELISA and FACS measured IFN-γ inplasma; ~3H-TdR measured T cell proliferation.Results: (1) CD40 could up-regulate the expression of CD25 (IL-2Ra) on Mo-DC, after...