TGF-beta favors bone marrow-derived dendritic cells to acquire tolerogenic properties

Dendritic cells (DCs) are the most powerful antigen-presenting cells that have an important role in the immunity and immune tolerance. Transforming growth factor beta (TGF-beta) is a pleiotropic cytokine widely expressing in various tissues and cells, which regulates cellular proliferation, differentiation and apoptosis of several immune cells and is considered to be a key factor in inducing immune tolerance. The effect of TGF-beta on DCs is very complex. In this study, we further investigated the effect of TGF-beta on inducing immune tolerance of DCs. DCs were differentiated from mice bone marrow cells in the absence or presence of TGF-beta. The phenotype as well as function was studied in detail. We found that TGF-beta limited the expression of CD40, CD83, CD86 and MHCII in DCs, increased CD45RB and indoleamine 2, 3-dioxygenase (IDO) expression in DCs, promoted IL-10 and limited IL-12 secretion by DCs. Moreover, TGF-beta increased the endocytosis ability of DCs and limited the ability of DCs in activating T cells. These results suggest that TGF-beta affects the immunity of DCs and enhances their tolerogenicity.