CD8A and autoimmune thrombocytopenic purpura: As shown in Fig. 4, representative dot plots of CD8+ Ki67+ , CD8+ GnB+ , CD8+ TNFα+ , CD8+ IFNγ+ , and CD8+ IL17+ cells in the PBMCs of HC, positive pathogen-ITP patient, and negative pathogen-ITP patient were shown in Fig. 4A, B, C, D and E. The percentages of CD8+ Ki67+ (Fig. 4F) and CD8+ IL17+ (Fig. 4J) cells were increased significantly in positive pathogen-ITP and negative pathogen-ITP patients than HC (p < 0.05).