Roles of follicular helper T cells and follicular regulatory T cells in pathogenesis of Henoch-Schönlein purpura in children

Abstract:

Objective To study the roles of follicular helper T (Tfh) cells and follicular regulatory T (Tfr) cells in the pathogenesis of Henoch-Schönlein purpura (HSP) in children. Methods Peripheral blood samples were collected from 40 HSP children and 25 healthy controls. The percentages of Tfh and Tfr cells were measured by flow cytometry;the mRNA expression levels of Bcl-6, c-MAF, Blimp-1, and PD-1 in peripheral blood were measured by real-time polymerase chain reaction. Results Compared with the controls, the children with HSP had significantly increased percentage of Tfh cells and Tfh/Tfr ratio but a significantly reduced percentage of Tfr cells in the peripheral blood (P<0.05). Compared with the controls, the children with HSP had significantly increased mRNA expression of Bcl-6 and c-MAF but significantly reduced mRNA expression of Blimp-1 in CD4⁺ T cells (P<0.05), and had significantly increased mRNA expression of PD-1 but significantly reduced mRNA expression of Blimp-1 in CD4⁺CD25⁺ regulatory T cells (P<0.05). Conclusions Abnormal percentages of Tfh and Tfr cells may be involved in the pathogenesis of HSP in children, and over-expression of Bcl-6, c-MAF, and PD-1 mRNA and inhibited expression of Blimp-1 mRNA may be considered as important reasons for abnormal percentages of Tfh and Tfr cells.