A Preliminary Study On The Biological Characters And Function Of Tolerogenic Dendritic Cells Induced By Tacrolimus

This experiment depicted the biological characteristics and immunosuppressive function on human tolerogenic dendritic cells (tDC) induced by tacrolimus based on that of human tolerogenic dendritic cells derived from peripheral blood mononuclear cells.Dendritic cells (DC) are the most important antigen-presenting cells (APC) in vivo and the only APC can induce the naive-T cells activation, they have the dual role of immune response and immune tolerance in immune system.As the deepening research on the heterogeneity of DC, the characteristic of immune tolerance has attracted the scientists’ attention in recent years. DC can be used on the treatment of organ transplantation and autoimmune diseases. Since the amount of DC is minimal in vivo, DC can’t meet the need of clinical research. So how to amplify and maintain the negative immune regulation function in vitro is the key to the clinical application. It is said in some research that medicines such as immunesuppressive agent (dexamethasone, rapamycin, cyclosporine A, deoxyspergualin), Aspirin, Vitamin D and other cytokines such as IL-10 and TGF-β can induce tDC. We established a method to induce tolerogenic dendritic cells with tacrolimus, and analyzed the biological characters and immunosuppression function of them in this paper.Human monocytes in the cGMP-compliant medium CellGro DC were treated with GM-CSF, IL-4 to obtain dendritic cells (DC), and replenished with immunosuppressive drugs tacrolimus to obtain tolerogenic DC (tDC). The molecular markers such as CD209, HLA-DR, CD80, CD83, CD86 of them and the livability were assayed by flow cytometry. tDC induced by tacrolimus exhibited a typical tolerogenic phenotype of reduced costimulatory molecules CD80, CD86, CD83 and HLA-DR. And immunosuppressive drugs didn’t influence the differentiation of DC from monocytes.Then the tolerance functionality of tDC induced by many agents such as IL-10, TGF-β, Dexamethasone, and Cyclosporin A were analyzed. These tDC modulated allogeneic CD4 T cells was determined via CFSE proliferation assay. Functional analyses showed that tDC induced by immunosuppressive drugs Dexamethasone, Cyclosporin A and tacrolimus had lower immunogenic than control DC and could not primed allogeneic CD4+T cells proliferation. Moreover tDC induced by tacrolimus can more effectively suppressed mature DC-induced T cell proliferation than other tDC. Importantly, tDC had phenotypical and functional stability after storage.Although it is studied that tDC can be induced by Dexamethasone, IL-10 and TGF-β etc, few research oftheir function of modulating allogeneic T cells by these tDC have been reported. tDC induced by tacrolimus with tolerance functionality in this research has also verified the immune function as well as their characteristic. It is demonstrated in this study that tDC induced by tacrolimus is a promising cellular therapeutic for immunomodulation. This study also provides the scientific experimental basis for the storage and clinical usage of tacrolimus.