Expression And Significance Of PD-1/PD-L1 In CD4+CD25+Treg/Th17 And Its Cells In Peripheral Blood Of Patients With Chronic Obstructive Pulmonary Disease

Objective:To explore the the role of CD4+CD25+Treg/Th17 in different stages of COPD,we detected the levels of CD4+CD25+Treg/Th17 in peripheral blood of patients with COPD and AECOPD and the healthy people.To discuss the correlations between Programmed Cell Death Protein 1(PD-1)and Programmed Cell Death ligand 1(PD-L1)expressed on CD4+CD25+Treg and Th17.Methods:There were 30 patients with AECOPD in the respiratory medicine department named as AECOPD group,30 patients with COPD named as COPD group,and 30 cases of healthy subjects with healthy physical examination in the medical center from Affiliated Hospital of Jining Medical College named as Healthy Controls(HC)group.Fluorescent antibody CD4/CD25 mark Treg,CD4/ CD25/ CD279 mark PD-1 expressed on Treg,CD4/IL-17 A mark Th17,CD4/IL-17A/CD279 mark PD-1 expressed on Th17,CD4/IL-17A/ CD274 mark PD-L1 expressed on Th17.Using flow cytometry analysis to detect the CD4+CD25+Treg/Th17 and CD4+CD25+Treg-PD-1 and Th17-PD-1/PD-L1 in the peripheral blood of AECOPD group,COPD group and HC group.To explore the roles of CD4+CD25+Treg/ Th17,PD-1/PD-L1 in COPD through discuss the correlations between CD4+CD25+Treg-PD-1and Th17-PD-1/PD-L1.Results:(1)Compared with the control group,the levels of CD4+CD25+Treg in AECOPD groups and SCOPD groups were significantly lower(P <0.05)than the control group,the levels of CD4+CD25+Treg in AECOPD groups were significantly lower(P <0.05)than the SCOPD groups;the levels of Th17 in AECOPD groups and SCOPD groups were significantly higher(P <0.05)than the control group,the levels of Th17 in AECOPD groups were significantly higher(P<0.05)than the SCOPD groups.(2)PD-1/PD-L1 expressed in peripheral blood CD4+CD25+Treg/Th17 cells was observed in all the subjects.PD-1expressed in peripheral blood CD4+CD25+Treg in AECOPD were significantly higher(P <0.05)than the control group,PD-1 expressed in peripheral blood CD4+CD25+Treg in SCOPD were significantly lower(P <0.05)than the control group.PD-1/PD-L1 expressed in Th17 in peripheral blood were significantly higher(P <0.05)than the control group,however,there was significant difference between the AECOPD group and the HC group(P<0.05),there was no significant difference between the SCOPD group and the HC group(P>0.05).(3)There is a positive coeeelation between CD4+CD25+Treg-PD-1 and Th17-PD-L1 in peripheal blood in COPD,the correlation coefficient is 0.49(P<0.05).Conclusion:(1)The imbalance of the proportion of CD4+CD25+Treg/ Th17 cells involved in the development of COPD,and the role of COPD in the pathogenesis of the opposite.(2)PD-1,PD-L1 expressed onTh17 cells of COPD and the correlation with infection.(3)There is a positive correlation between CD4+CD25+Treg-PD-1 and Th17-PD-L1 in peripheral blood in COPD,which suggested that the relationship between the two may be receptor.In patients with COPD which may regulate CD4+CD25+Treg/ Th17 through the PD-1/PD-L1 pathway.