The Significance Of Lymphocyte Subsets And PD-1/PD-L1 In Ulcerative Colitis

Objective:1.The significance of lymphocyte subsets in ulcerative colitis(UC):To explore the disorder of lymphocyte subsets in peripheral blood of patients with UC,the value of lymphocyte subsets in predicting and evaluating the condition of patients with UC,and effects of CMV and EB infection on lymphocyte subsets in UC,the effects of CMV and EB infection on lymphocyte subsets were also analyzed;2.Expression and significance of Programmed cell death-1(PD-1)and Programmed cell death ligand-1(PD-L1)in ulcerative colitis(UC):To investigate the expression and significance of in PD-1/PD-L1 mucosal tissues and peripheral blood of patients with UC.Methods:1.The significance of lymphocyte subsets in ulcerative colitis(1)Flow cytometry was used to detect the percentages and ratios of T cells,B cells,CD4+T cells,CD8+T cells,NK,Treg,Th1,Th2,reg and Th17 cells in peripheral blood of UC group;The amount of CMV DNA and EB DNA in mucosal tissues was detected by PCR fluorescence probe;2.Expression and significance of PD-1/PD-L1 in ulcerative colitis(1)PD-1 and PD-L1 expression was assessed by immunohistochemistry in mucosal tissues.An enzyme-linked immunosorbent assay was used to measure soluble PD-1 and PD-L1 levels in peripheral blood serum,and the expression levels of PD-1/CD3+T,PD-1/CD4+T,PD-1/CD8+T cells,Thl and Th17 in peripheral blood were detected by flow cytometry.Results:1.The significance of lymphocyte subsets in ulcerative colitis(1)The percentage of Th1,Th2,Th17 and Th17/Treg,Th1/Treg and Th2/Treg in peripheral blood of UC group were significantly higher than that of control group(P<0.001),and the percentage of Treg in peripheral blood of UC group was significantly lower than that of normal control group(P<0.001).The percentage of Th17 cells,Th1/Treg and Th2/Treg in severe UC group were higher than those in mild and moderate UC group(P<0.05).The percentage of Treg cells in mild UC group was higher than that in moderate and severe UC group,while the percentage of Th1 cells in mild UC group was lower than that in moderate and severe UC group(P<0.05);(2)The AUC of combined detection was 0.941,Th1(AUC=0.921,cut off value 15.25%),Th2(AUC=0.785,cut off value 2.95%),Th17(AUC=0.874,cut off value 1.95%),Th1/Treg(AUC=0.933,cut off value 4.885),Th2/Treg(AUC=0.849,cut off value 0.485),Th17/Treg(AUC=0.923,cut off 0.425)(P<0.001);(3)Th and Treg cells were negatively correlated with the improved Mayo score,while Th17,Th17/Treg,Th1/Treg and Th2/Treg were positively correlated with the improved Mayo score(P<0.05),and Th17/Treg was correlated with the improved Mayo score(r=0.513,P<0.001);(4)The Th cell percentage and Th/CTL value in the UC group infected with CMV were lower than those in the UC group without CMV(P<0.05).The percentage of CTL,Th17 cells and Th17/Treg in UC group infected with CMV were higher than those in UC group not infected with CMV(P<0.05).The percentage of CTL cells in the UC group infected with Epstein-Barr virus were higher than those in the UC group without EB infection,the Th cell percentage and Th/CTL value in the UC group infected with EB were lower than those in the UC group without EB infection(P<0.05).2.Expression and significance of PD-1/PD-L1 in ulcerative colitis(1)PD-1 expression was observed only in monocyte of mucosal lamina propria of UC patients,While for PD-L1,it was mainly located in both epithelial cells and in monocyte on the cell membrane,PD-1/PD-L1 expression was negative in intestinal mucosal tissues of normal and common acute enteritis and and there were statistical differences in the expression of PD-1/PD-L1 in the mucosal tissues of UC groups with different disease activity(p<0.05);(2)The percentages of PD-1/T,PD-1/CD4+T in peripheral blood of UC and healthy control group were significantly different(P<0.05),and the moderate UC group(PD-1/T 12.83 ± 6.15%,PD-1/CD4+T 19.67±9.95%)and severe UC group(PD-1/T 14.29±5.71%,PD-1/CD4+T 21.63±11.44%)had higher expression level than mild UC group(PD-1/T 8.17±2.80%,PD-1/CD4+T 12.44±4.73%)(P<0.05);(3)sPD-L1 in normal group(232.27±65.93pg/ml)and UC group(mild group(256.38 ± 80.23pg/ml),moderate group(350.30 ± 95.67pg/ml),severe group was 441.64±8 5.57pg/ml)and the expression of sPD-Ll in peripheral blood was statistically different between the UC groups with different disease severity,and the expression of sPD-L1 increased with the disease severity(P<0.05).Conclusion:1.The immune disorder of T lymphocyte subsets is the main cause of cellular immune disorder in UC patients.The combination of Th1,Th2,Th17,Th1/Treg,Th2/Treg and Th17/Treg in the prediction and evaluation of UC has certain clinical application value;2.CMV and EB infection further affect the function of T lymphocyte subsets in UC patients,and clinical detection of CMV and EB in UC patients is of great significance;3.The expression of PD-1/PD-L1 was positive in the intestinal mucosal tissues of UC patients,but negative in acute enteritis and normal mucosal tissues.PD-1/PD-Ll is an important signaling molecule in the chronic inflammatory response of UC;4.The expression levels of PD-1/PD-L1 in tissue mucosa of UC patients,PD-1 on T lymphocytes and soluble PD-L1 in peripheral blood increased with the disease activity of UC.Two forms of PD-1/PD-L1 can be used to explore the etiology of UC and evaluate the disease condition of UC.