Abstract: Objective To compare the efficacy of two blood cell separator in reduction of blood group antibody titers in renal transplants with incompatibility of blood groups. Methods Plasma exchange was performed on 23 patients with ABO incompatible renal transplant recipients between 2015 and 2017 by using the CS-3000 and COM.TEC blood cell separators. Results CS-3000 gave rise to the replace of 1.3±0.5 plasma volume and COM.TEC resulted in the replace 0.9±0.2 plasma volume for a half reduction of the antibody titers. The procedure time to exchange one plasma volume was 95.2±10.4 min with the CS-3000 and 75±11.2 min with the COM.TEC （P<0.001）. The plasma removal efficiency （PRE） was 39.7±4.9% with the CS-3000 and 48.2±3.7% with the COM.TEC （P<0.001）. In comparison with the blood components before plasma exchange，the platelet counts of patients with the CS-3000 blood cell separator replacement obviously decreased by an average of 25.42% while those of patients with the COM.TEC reduced by 12.56%. Conclusion Compared with the CS-3000，the COM.TEC might improve PRE and have short procedure time and slight losses of platelet counts for exchange of one plasma volume. Additionally，the COM.TEC is suitable for kidney transplant recipients with high initial antibody titers and low number of platelets.

Key words: Blood cell separators, Therapeutic plasma exchange , ABO-incompatible kidney transplantation