Activin A, a multifunctional factor of the transforming growth factor-beta （TGF-β） superfamily, is mainly produced by microglia and macrophages, and its anti-inflammatory and pro-inflammatory activities are both related to macrophage functions. However the direct effect of activin A on the rest macrophages in vivo remains unclear. In the present study, the results showed that activin A not only increased NO and IL-1β release, but also promoted phagocytic abilities of mouse peritoneal macrophages in vitro and in vivo, whereas it did not influence MHC Ⅰ and MHC Ⅱ expression. Moreover, we found that activin A significantly upregulated the expressions of CD14 and CD68, markers of mature macrophages, on the surface of macrophages in vitro and in vivo. These data suggest that activin A can induce primary macrophage maturation in vitro and in vivo, but may not trigger the acquired immune response via regulating expression of MHC molecules involved in presentation of antigen.
Yinan WangXueling CuiGuixiang TaiJingyan GeNan LiFangfang ChenFang YuZhonghui Liu
Macrophages play critical roles in innate immune and acquired immune v/a secreting pro-inflammatory mediators, phagocytosing microorganisms and presenting antigens. Activin A, a member of transforming growth factor （TGF-β） superfamily, is produced by macrophages and microglia cells. In this study, we reported a direct effect of activin A as a pro-inflammatory factor on mouse macrophage cell line RAW264.7 cells. Our data revealed that activin A could not only increase IL-1β and IL-6 production from RAW264.7 cells, but also promote pinocytic and phagocytic activities of RAW264.7 cells. In addition, activin A obviously up-regulated MHC Ⅱ expression on the surface of RAW264.7 cells, whereas did not influence MHC I expression. Activin A also enhanced CD80 expression, which is a marker of activated macrophages, but did not influence RAW264.7 cell proliferation. These data suggest that activin A may regulate primary macrophage-mediated innate and acquired immune response via promoting the activation of rest macrophages.
Jingyan GeYinan WangYe FengHaiyan LiuXueling CuiGuixiang TaiZhonghui Liu
