[Analysis of Correlation between Platelet Desialylation, Apoptosis and Platelet Alloantibody and CD8+ T Cells in Platelet Transfusion Refractoriness].

Objective: To investigate the correlation between platelet alloantibodies and CD8⁺ T cell with platelet desialylation and apoptosis in platelet transfusion refractoriness(PTR).

Methods: The expression of RCA-1, CD62P and Neu1 on platelets were detected in 135 PTR patients and 260 healthy controls. The ability of PTR patients' sera with anti-HLA antibody, anti-CD36 antibody and antibody-negative groups to induce platelet desialylation and apoptosis, and the potential effect of FcγR inhibitors on desialylation and apoptosis were evaluated. Additionally, the association between CD8⁺ T cells and platelet desialylation in patients was analyzed.

Results: The expression of RCA-1 and Neu1 on platelets in PTR patients were significantly higher than those in healthy donors（P < 0.05）, but were not related to platelet alloantibody (P >0.05). The sera of PTR patients generally induced platelet desialylation in vitro （P < 0.05）, with no significant differences among the groups（P >0.05）. However, the sera with anti-CD36 antibodies could induce platelet apoptosis significantly higher than that in the anti-HLA antibody group and antibody-negative group in vitro (P < 0.05). In PTR patients with anti-CD36 antibodies, platelet apoptosis was dependent on FcγR signaling, while desialylation is not. Moreover, CD8⁺ T cells in PTR patients were significantly associated with platelet desialylation (P < 0.05).

Conclusion: Platelet desialylation is a common pathological phenomenon in PTR patients， which involves the participation of CD8⁺ T cell, but isn't associated with platelet alloantibody; while anti-CD36 antibodies have potential clinical significance in predicting platelet apoptosis in PTR patients.