In Vitro Study Of Inhibitory Effects Of SCD83 By Inducing Tolerant DC And Regulatory T Cells

Objective:To explore the immune tolerance effect and possible mechanism of sCD83in vitro,and to provide experimental evidence for its transformation into clinical practice.Method:The method of co-cultivating sCD83 with dendritic cells(DC)and lymphocytes(TC)in vitro is divided into the following four groups:Group 1:DC+TC group;Group 2:DC+TC+sCD83 group;Group3:DC+TC+sCD83+1-MTgroup;Group4:DC+TC+sCD83+anti-TGFβ1 group.Cell culture was mixed according to the ratio of DC:TC=1:10 in all groups.The concentration of sCD83 was 3μg/m L in group 2,3and 4;0.1mg/m L 1-MT was added in group 3,and 5ng/m L of anti-TGFβ1 was added in group 4.Morphological and differential changes of DC was observed and traced with microscope in DC and TC co-culture system before and after sCD83 and related antibodies were added.q PCR was explored to analyze the transcription level of Foxp3,TGF-β1 and IDO m RNA;ELISA was explored to compare the changes in the expression levels of cytokines IL-2,IL-10,IFN-γ,and TGF-β1;Flow cytometry was used to detect the expression level of costimulatory moleculesCD86,CD80,MHC-II on the surface of DC,and the expression of IDO~+DC,CD4~+TGFβ1~+T,CD4~+CD25~+Foxp3~+T(Treg)cells.Results:sCD83 can reduce the secretion of IL-2 and promote the secretion of IL-10,IFN-γand TGF-β1.Promoting the m RNA expression of Foxp3,TGF-β1 and IDO;The expressions of CD80,CD86 and MHCII on the surface of DC cells were decreased,and the expression of IDO on the surface of DC cells was increased.The ratio of CD4~+TGF-β1~+and CD4~+CD25~+Foxp3~+T(Treg)were increased.Conclusion:The co-culture of sCD83 with DC and T lymphocytes showed that sCD83 had the effect of immune tolerance.The mechanism may be related to the increase of TGF-β1 expression by sCD83,activation of IDO immunosuppressive pathway,and increase of tolerance to DC and Treg cells.