CD4 and autoimmune thrombocytopenic purpura: In addition, the number of CD4+CD8+, CD4+CD8−, CD4−CD8−, and CD4−CD8+ subsets of MAIT cells in patients with ITP were significantly lower than those in HCs (p < 0.0001) (Fig 1B, 1C, 1D and 1E), and the frequency of CD4−CD8− and CD4−CD8+ subsets of MAIT cells within blood CD3+ T cells were significantly lower than those in HCs (p = 0.0377 and p = 0.0048, respectively) (Fig 1D and 1E).