HLA-DRB1 and Sepsis: Additional experiments revealed that the observed elevation in CTCF expression, CTCF binding at CM1, CM2, CM3 and CM9 as well as the reduced expression of adjacent classical HLA genes HLA-DRA, HLA-DRB1, HLA-DPA1 and HLA-DPB1 persisted in all patients with postoperative sepsis (S7–S9 Figs).