Analysis of Frequencies and Subsets of Peripheral Helper T Cells in Patients with Immune Thrombocytopenia
Objective:To investigate the frequencies and subset distribution of peripheral helper(Tph)T cells in patients with immune thrombocytopenia(ITP),and explore the pathogenesis of ITP.Methods:A total of 25 newly diagnosed ITP patients treated in The Second Affiliated Hospital of Dalian Medical University from January to December 2022 were selected,and 25 healthy volunteers(age-and sex-matched)were recruited as the control group.Flow cytometry was used to detect the subsets of CD4+T cells and Tph cells.Results:The frequency of effector memory(CCR7-CD45RO+CD4+)T cells in ITP patients was significantly higher than that in healthy controls(P<0.05).The frequency of Tph cells in ITP patients was also significantly higher than that in healthy controls(P<0.001),and most of the Tph cells in ITP patients were effector memory T cells.Furthermore,the expressions of T-cell costimulatory molecules in Tph cells,including ICOS and CD84,were similar to those in follicular helper T(Tfh)cells.CXCR3-CCR6-Tph(Tph2)subgroup was dominant in Tph cells,but the frequency of CXCR3+CCR6-Tph(Tph1)cells in ITP patients was much higher than that in healthy controls(P<0.05).Conclusion:Tph cells,especially Tph1 cells,were abnormally expanded in ITP patients,which may be a potential etiology of ITP.
peripheral helper T cellsimmune thrombocytopeniaCD4+T cells