ANXA5 and autoimmune thrombocytopenic purpura: The percentage of apoptotic cells were considered as Annexin V‐positive and PI‐negative.12 Indirubin could only induce the apoptosis of PMBCs from ITP patients at higher doses of 2 and 10 μmol/L (Figure 2F,H), and the apoptosis level of PBMCs from healthy controls did not change much after indirubin treatment (Figure 2G).