Study On Immunosuppressive Factors Of Chronic Obstructive Pulmonary Diseasee

Objective By detecting the expression of TIGIT,PD-1,Tim-3,CTLA-4immunoregulatory factors,analyze and compare their differences in patients with COPD and healthy controls,to understand whether they play a role in the pathogenesis of COPD.Methods A total of 27 patients with COPD who were in clinical remission from January 2019 to December 2019 were selected as the case group.22 healthy controls of our hospital's physical examination center were selected at the same period.Flow cytometry was used to detect the expression of TIGIT,PD-1,Tim-3 and CTLA-4 on CD4⁺T cells and CD8⁺T cells on peripheral blood mononuclear cells.Fifteen cases were selected from the above-mentioned COPD group and healthy control group respectively,and CCR7 and CD45RO on CD8⁺T cells were detected by flow cytometry for cell status grouping,and TIGIT,PD-1,Tim-3,and CTLA-4 Different expression in different cell subpopulations.In addition,the expression of CD155 on the alveoli and airways in lung tissues of patients with COPD and healthy controls was measured by immunohistochemistry.Results1.Flow cytometry results show:?1?Proportion of CD4⁺T cells and CD8⁺T cells:The proportion of CD4⁺T lymphocytes in peripheral blood mononuclear cells in the COPD group was significantly lower than that in the healthy control group,p<0.05,the difference was statistically significant.The ratio of peripheral blood CD8⁺T lymphocytes and Treg cells in the COPD group was higher than that in the healthy control group,but there was no statistical significance,p>0.05.?2?The proportion of TIGIT,PD-1,Tim-3 and CTLA-4 expressed in CD4⁺T cells and CD8⁺T cells:CD4⁺CTLA-4⁺T cells were significantly higher in the COPD group than in the healthy control group,p<0.05,the difference was statistically significant;CD4⁺PD-1⁺T cells were higher in the COPD group than the healthy control group,p<0.05,the difference was statistically significant;while CD4⁺TIGIT⁺T cells and CD4⁺Tim-3⁺T Cells had an increasing trend in the COPD group,but p>0.05,which was not statistically significant.CD8⁺TIGIT⁺T cells were higher than the healthy control group,p<0.05,the difference was statistically significant;CD8⁺PD-1⁺T cells were higher in the COPD group than the healthy control group,p<0.05,the difference was statistically significant;CD8⁺Tim-3⁺T cells were higher in COPD group than healthy control group,p<0.05,the difference was statistically significant;CD8⁺CTLA-4⁺T cells were higher in COPD group than healthy control group,p<0.05,the difference was statistically significant learn.?3?Comparison of the expression of TIGIT,PD-1,Tim-3 and CTLA-4 in CD4⁺T cells and CD8⁺T cells:whether in healthy control group or COPD group,the percentage of TIGIT and Tim-3 in CD8⁺T lymphocytes were significantly higher than the percentage of TIGIT and Tim-3 in CD4⁺T cells in the same group,both of which were p<0.0001,the difference was statistically significant.No matter in the healthy control group or the COPD group,there was no significant difference in the percentage of PD-1 between CD4⁺T lymphocytes and CD8⁺T lymphocytes,p>0.05.However,in the healthy control group and the COPD group,the percentage of CTLA-4 in CD8⁺T lymphocytes was significantly lower than the percentage of CTLA-4 in CD4⁺T lymphocytes in the same group p<0.0001,the difference was statistically significant.?4?CD8⁺T cell subgroups:CD8⁺T cells were labeled with CD45RO and CCR7 and divided into four subgroups:primitive T cells?T_N,CCR7⁺CD45RA^-?,central memory T cells(T_CM,CCR7⁺CD45RA⁺),effector memory T cells(T_EM,CCR7^-CD45RA⁺)and terminally differentiated effector cells(T_EMRA,CCR7^-CD45RA^-).Among CD8⁺T cells,the proportion of terminal effector cells(T_EMRA)was the highest,and the proportion of T_EMRA in COPD group was higher than that in healthy control group,p<0.05,the difference was statistically significant.Compared with the healthy control group,the initial CD8⁺T cells in the COPD group were significantly reduced,p<0.05,and the difference was statistically significant.Effector memory T cells(T_EM)were higher in the COPD group than in the healthy control group,but there was no statistical difference,p>0.05.?5?Proportions of TIGIT,PD-1,and Tim-3 in different CD8⁺T cell subsets:The percentage of TIGIT in terminal effector CD8⁺T cells(T_EMRA)in the COPD group was higher than that in the healthy control group,p<0.05,the difference is statistically significant.TIGIT showed no significant difference between central memory T cells(T_CM)and effector memory T cells(T_EM)in the healthy control group and the COPD group.The proportion of Tim-3 in central memory T cells(T_CM)in the COPD group was higher than that in the healthy control group,p<0.05,the difference was statistically significant;in the COPD group,the effect of memory T cells(T_EM)was higher than in the healthy control group,p<0.05,the difference is statistically significant.There was no significant difference in the proportion of Tim-3between initial T cells and terminal effector T cells(T_EMRA).PD-1 was only on the initial T cells?T_N?,the COPD group was higher than the healthy control group,p<0.05,the difference was statistically significant.There was no significant difference in the percentage of PD-1expression between the other two subgroups.2.The result of immunohistochemistry show:Immunohistochemical results showed that,as a high-affinity ligand of TIGIT,the expression of CD155 on airway epithelial cells and alveoli in patients with COPD increased compared with healthy controls.Conclusion1.In patients with COPD,the ratio of effector and regulatory T cells is unbalanced;the inhibitory immunomodulatory factors CTLA-4,TIGIT,PD-1,Tim-3 increase or show an increasing trend,suggesting that these immunomodulatory factors affect the Immune Function.In addition,the expression ratio of CTLA-4 on CD4⁺T cells was significantly higher than that on CD8⁺T cells,while the expression of TIGIT and Tim-3 on CD8⁺T cells was significantly higher than that on CD4⁺T fine cells,suggesting that different in COPD The effect of immunosuppressive factors on different effector T cells is different.2.End effector T cells?TEMRA?in COPD patients increased significantly,while TIGIT expression on TEMRA CD8⁺T cells in COPD patients increased,while Tim-3 expression on TEM CD8⁺T cells in COPD patients increased.It is suggested that the damage of CD8⁺T cells to TIGIT may be more obvious in COPD.3.Immunohistochemical results showed that the expression of CD155 in the alveoli and airways was higher in the COPD group than in the healthy control group.It is suggested that as a high-affinity ligand of TIGIT,CD155 plays a role in the pathogenesis of COPD.