The Experimental Study On How The Exosome Secreted From The Dendritic Cells Of Mouse Influence The Proliferation Of Allogeneic T Cell

Objective：To explore the phenotypic variation of exosome extracted from mousebone marrow-derived dendritic cells(DC) managed from different means, and itsinfluences to the proliferation of allogeneic T lymphocyte derived from mouse spleen,and the mechanism of its influences;To optimize the DC culture protocol and study themechanism of the influence between the exosome extracted from DC and T lymphocyte.Methods: The DC was co-cultured by LPS(pathogenic microbial products), or byLPS+IL-10(inhibit inflammatory cytokine), or LPS+glucocorticoid dexamethasone andthen the surface marker of DC was assayed.There are five groups:A,5days withouttreatment group, B:7d LPS group, C:7d glucocorticoid dexamethasone group, D:7dIL10group, E:7d without treatment groups. Exosome extracted from mouse DC underdifferent culture conditions was used to address the effects on T cell proliferation by mixedlymphoid reaction(MLR).The T cell plus imDC derived from the ICR mouse and theExosome extracted from the Kunming mouse was used to simulate the mixed lymphocytereaction（MLR），the test of CCK-8was used to calculate the inhibition rate ofproliferation of allogeneic T cell induced by the Exosome in each group.The results:(1)the expression level of surface molecules MHC-II, CD80and CD86are as follows: the statistically significance (P <0.05) occurred between LPS group and theother four groups.(2) the Exosome extracted from each group is as follows: MHC-IIexpression of B group was significantly different (P <0.05) compared with the other fourgroups respectively, CD80expression of group C compared with group A and group Erespectively(P <0.05). T cell proliferation inhibition rate induced by exosome extractedfrom each group is as follows: There was significant difference (P <0.05) between thegroups, and within each group (P <0.05).Conclusions:(1) the expression of surface molecules of DC,such as MHC-II, CD80 and CD86is increased gradually during the maturation of DC process,LPS can stimulateimmature DC(imDC) into mature,meanwhile dexamethasone and IL-10have anantagonistic effect of LPS, and lower down the expression of surface molecules MHC-II,CD80and CD86.(2) the expression of surface molecules of exosome is dependent on theirsource cells.(3)Exosome extracted in each group inhibits the proliferation of T cell in thepresence of imDC.The inhibition rate of T cell proliferation is correspondingly increasedwith the amount of exosome.The inhibition of T cell proliferation was the best in allgroups.