APOO and autoimmune thrombocytopenic purpura: Gene expression analysis showed that APOO, CCR7, and protein tyrosine phosphatase, receptor type C-associated protein (PTPRCAP) were enriched in CD4+CCR7+T cells from normal individuals, while SP100, FOXP1, ANXA1, and CDK6 were upregulated in ITP-derived cells (Figure 4C).