In 17 ITP patients in cohort 2, the protein expression of COX-2 protein was positively related with platelet count (r = 0.5034, p = 0.0394) (Fig. 1E) and negatively correlated with Caspase-1 expression (r = -0.5971, p = 0.0114) (Fig. 1F), but not significantly correlated with Caspase-1, or Caspase-3 p17 subunit expressions (Additional file 1: Fig. S5A–C). Here, PTGS2 is linked to autoimmune thrombocytopenic purpura.