The Clinical Significance Of T Lymphocyte Subsets And Their PD-1 Expression In Peripheral Blood Of Patients With Rheumatoid Arthritis

Rheumatoid arthritis(RA)is a systemic autoimmune disease characterized by chronic,joint synovial inflammation,repeated relapse and joint dysfunction.The pathological mechanism remains unknown.Recent researches have indicated that a number of costimulatory molecules took part in the pathologic processes of autoimmune diseases.Recently,programmed cell death protein 1(PD-1)was identified as one of the most effective immune checkpoint to T cell responses.The inhibitory signals provided by ligation of PD-1 and its ligands PD-L1/2 leads to maintenance of the necessary homeostasis between T cell activation and tolerance.This study discusses PD-1 expression on T cell subsets and its clinical significance in different pathological stages of RA patients.Objective: To evaluate PD-1 expression on T lymphocyte subsets peripheral blood from active RA patients(active),inactive(remission)and healthy controls(control),and the correlation with clinical laboratory indexes.Methods: The fresh peripheral blood was collected from 44 patients with active RA diagnosis,34 patients in remission and 31 healthy donors.T lymphocyte subsets and their PD-1expression were detected by flow cytometry.And then,the correlation between PD-1 expression and the clinical diagnostic indexes of the RA patients was analyzed.Results: 1.In RA patients,the percentages of CD3+T cells and CD3+CD8+T cell were reduced(P<0.01).The percentages of CD3+CD4+T cell,CD4+PD-1+T cell,CD8+ PD-1+T cell and the ratio of CD4+T/CD8+T cell were increased(P<0.01).2.There is no correlation between PD-1 expression and the gender and age.The percentage of T cell subsets,PD-1 expression are correlated with the blood sedimentation,CRP and anti CCP antibody.3.The percentage of CD3+CD8+T cell of the same patients was decreased in remission phase compared with that in active phase(P<0.05);and the percentages of CD3+CD4+T,CD4+T/CD8+T,CD4+PD-1+T and CD8+PD-1+T cell in active phase was significantly higher than those in remission phase(P<0.01).Conclusion: PD-1 expression on T subsets plays an important role in the immune pathological process.PD-1 expressed on T cell subsets was associated with RA clinical and laboratory examination indexes,and its expression reflects the pathological process of RA.The expression of PD-1 on T cells is a promising and new indicator to the prevention,diagnosis,monitoring and treatment of RA.