CD8A and autoimmune thrombocytopenic purpura: The binding level of Ricinus communis agglutinin I (RCA-I) on platelets, which was represented by the mean fluorescence intensity (MFI) of RCA-I, was significantly higher in the cytotoxic group than in the non-cytotoxic group and controls (MFI of RCA-I: cytotoxic vs. non-cytotoxic, 5.95 ± 1.92 vs. 4.14 ± 2.44, respectively, P = 0.008; cytotoxic vs. controls, 5.95 ± 1.92 vs. 2.80 ± 1.12, respectively, P < 0.001; Fig. 2a,b), revealing a potential association between the cytotoxicity of CD8+ T cells and platelet desialylation in ITP.