Alteration of T follicular helper cells in children with persistent immune thrombocytopenic purpura / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the role of T follicular helper ( Tfh) cells in the immuno-pathogenesis of persistent immune thrombocytopenic purpura ( pITP) .Methods Twenty children with pITP and twenty healthy controls were enrolled in this study .The proportion of CD4+CXCR5+ICOShigh PD-1high T ( cTfh) cells and the expression of ICOSL on CD 19+B cells in peripheral blood of the patients and healthy subjects were analyzed by flow cytometry .The expressions of Bcl-6, c-Maf, IL-21 and ICOSL at mRNA level were detected by real-time PCR.The plasma concentrations of IL-2, IL-6 and IL-21 were determined by ELISA.Results (1) Compared with the healthy controls , the proportions of cTfh cells increased signifi-cantly in patients with pITP [(17.45±9.04) %vs.(7.57±2.57) %, P0.05).(4) The plasma concentration of IL-21 was remarkably elevated in patients with pITP , regardless of DEX treatment (P0.05).Con-clusion The immunopathogenesis of persistent immune thrombocytopenic purpura might be associated with the hyper-activation of Tfh cells caused by excessive expression of ICOSL and IL-21.The persistent high expression of ICOSL and IL-21 might be one of the important factors resulting in the recurrence of pITP in children .