Abstract: Objective To investigate the changs and characteristics of regulatory T cells (Treg), helper T cells 17 (Th17) and related cytokines in the peripheral blood of patients with immune platelet transfusion refractoriness (IPTR). Methods A case-control study was conducted involving 20 patients with IPTR, 20 patients with effective platelet transfusion and 20 healthy controls. Flow cytometry was applied to detect the proportions of Treg (CD4+CD25+Foxp3+) and Th17 (CD4+IL-17A+) cells. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum levels of interleukin-6 (IL-6), interleukin-10 (IL-10), interleukin-17A (IL-17A) and transforming growth factor-β1 (TGF-β1). Results Compared with the healthy control group, the IPTR group showed a significantly decreased proportion of Treg (P<0.05), accompanied by a significantly increased proportion of Th17 cells and an elevated Th17/Treg ratio (both P<0.05). Meanwhile, the serum levels of pro-inflammatory cytokines IL-6 and IL-17A were significantly elevated (both P<0.05), while the levels of anti-inflammatory cytokines IL-10 and TGF-β1 were significantly reduced (both P<0.05). Conclusion Patients with IPTR have an imbalance in the Treg/Th17 axis and dysregulation of the pro-inflammatory and anti-inflammatory cytokine network. This finding suggests that the disruption of immune homeostasis may contribute to the pathogenesis of PTR by enhancing inflammatory responses and impairing immune tolerance.

Key words: Immune platelet transfusion refractoriness, Regulatory T cells, Helper T cells, Cytokines, Immune homeostasis