This revealed a number of genes whose expression positively correlated with TTP including those involved in the adaptive immune response (PDCD1, HAVCR2, CCL5, CD244), compared to genes involved in proliferation/DNA damage (MSH6, LDHB, BIRC5, EGFR), which were negatively correlated. This evidence concerns the gene PDCD1 and thrombotic thrombocytopenic purpura.