[The decreased number of regulatory T cells in peripheral blood is accompanied by decreased autophagy in pediatric immune thrombocytopenia].

Objective To detect the number of CD4+CD25+FOXP3+ regulatory T cells (Tregs) and the expression of autophagy related proteins in autoantibody positive children with immune thrombocytopenia (ITP). Methods Flow cytometry was used to sort Tregs in peripheral blood of newly-diagnosed ITP children or healthy donor controls, the expression of autophagy related gene ATG5 or ATG7 was calculated by their mean fluorescence intensity, and the phosphorylation of protein kinase B (AKT) or extracellular signal regulatory kinase (ERK) of CD4+CD25+ Tregs was determined by Western blot analysis. Results Compared with healthy donor control, the number of Tregs in ITP children decreased significantly, the expression of ATG5 and ATG7 decreased, and the phosphorylation of AKT and ERK decreased significantly. Conclusion In newly-diagnosed auto-antibody positive ITP children, the number of Tregs is reduced, and the levels of protein phosphorylation related to the proliferation and autophagy of Tregs is decreased.