Anti-CD45RB monoclonal antibody induces immunologic toleration by suppressing dendritic cells

Abstract Background In transplantation, the antigen presentation step of T cell activation determines whether the T cell rejects the graft, ignores the graft, or inhibits other T cells from attacking the graft. Dendritic cells (DCs) are the most potent antigen presenting cells that are capable of activating naive T cells. The purpose of the present study was to investigate the influence of anti-CD 45 RB monoclonal antibody on the phenotypes and functions of DCs and to further illustrate the mechanism of anti-CD 45 RB monoclonal antibody-inducing immunologic tolerance. Methods DCs from mice were cultured and treated with varying doses of anti-CD 45 RB monoclonal antibody at specific time points. Fluorescence-activated cell sorting (FACS) was used to verify the changes of phenotypes in the cultured DCs labeled with fluorescent antibody. DCs were also used as stimulators in mixed leukocyte reaction to detect their ability to stimulate T cell proliferation. Results Anti-CD 45 RB monoclonal antibody induced a dose- and time-dependent suppression of maturation of DCs and a dose-dependent suppression of T cell proliferation in mixed leukocyte reaction when anti-CD 45 RB monoclonal antibody-treated DCs were used as stimulators. Conclusions One of the mechanisms of anti-CD 45 RB monoclonal antibody-induced tolerance was inhibiting maturation and function of DCs and inducing tolerogenic DCs to achieve a new immune balance.