Effects Of Adipose-derived Stem Cells On Regulating The Ability Of Heterologous CD4~+T Cells To Secrete Cytokines

Objective:As an important group of T cells,CD4~+T cells are divided into several subsets due to the different cytokines secreted by T cells.The role of each subset of T cells in the pathogenesis of autoimmune diseases has been widely studied and affirmed in the past decade.Adipose-derived stem cells are multipotent mesenchymal cells that have the ability to differentiate into adipocytes,osteoblasts,and chondrocytes.More and more recent studies have shown that autologous or allogeneic ADSCs have a unique ability to play a regulatory role in adaptive and innate immunity.CD4~+T cells can be divided into Th0,Th1,Th2,Tfh,Th3 and Th17 according to different secretory factors.Current studies on autoimmune diseases have shown that the imbalance of Th1/Th2 cells’immune response leads to the occurrence and development of diseases,and Th1 cells are the key factor mediating the occurrence and development of autoimmune diseases.Current studies have shown that ADSCs can regulate Th1/Th2 imbalance caused by immune response and regulatory T cell function,thereby inhibiting or reversing the inflammatory process.Selecting ADSCs to readjust the cellular immune Th1/Th2balance in patients and to search for specific effector T cells will be an innovative design strategy.Phytohemagglutinin is a compound of oligosaccharides and proteins,which can stimulate the proliferation and differentiation of T cells.This study intends to simulate the inflammatory microenvironment of autoimmune diseases,to explore the influence of ADSCs on the ability of CD4~+T cells to secrete inflammatory factors,and then to infer the regulatory mechanism of ADSCs on cellular immunity of autoimmune diseases.Methods:1.Isolation,culture and identification of ADSCs.2.CD4~+T cells in PBMC were isolated and cultured by immunomagnetic bead method.3.Activate CD4~+T cells with PHA and check the results after activation to verify the changes of inflammatory cytokines secreted by CD4~+T cells after activation.4.Pretreat h ADSCs with IFN-γand TNF-αfor 24h to activate the immune adjustment ability.Co-cultrue PHA activated CD4~+T cells and pretreated h ADSCs for 24h,and then test the level of IFN-γ,TNF-α,IL-10 and the IL-4 in the supernatant fluid.5.Analyze the data using SPSS19.0 and Graph Pyramid 5 software.P<0.05 was considered statistically significant.Results:1.h ADSCs,PBMC and CD4~+T cells were successfully isolated;2.PHA can effectively activate CD4~+T cells and promote the secretion of pro-inflammatory cytokines,such as IFN-γ,TNF-α,IL-4 and IL-10(P<0.05);3.IFN-γand TNF-αpretreated ADSCs can effectively inhibit the secretion of IFN-γand TNF-αby PHA activated CD4~+T cells(P<0.05),promote the secretion of IL-10,and there is no significant difference in IL-4 secretion(P>0.05).Conclusion:1.It was confirmed that PHA stimulated CD4~+T cells to secrete more IFN-γ,TNF-α,IL-4 and IL-10.2.ADSCs pretreated by inflammatory factors can significantly inhibit the secretion of IFN-γand TNF-αof CD4~+T cells after PHA stimulation,and promote the secretion of IL-10 and IL-4.It was confirmed that ADSCs had an inhibitory effect on inflammatory immune response.