Propensity of red blood cells to undergo P2X7 receptor–mediated phosphatidylserine exposure does not alter during in vivo or ex vivo aging

摘要: BACKGROUND Phosphatidylserine (PS) exposure facilitates the removal of red blood cells (RBCs) from circulation, potentially contributing to loss stored RBCs after transfusion, as well senescent RBCs. Activation P2X7 receptor by extracellular adenosine 5′-triphosphate (ATP) can induce PS on freshly isolated human RBCs, but whether this process occurs in or changes during RBC aging is unknown. STUDY DESIGN AND METHODS RBCs were processed and according Australian banking guidelines. was determined annexin V binding flow cytometry. Efficacy P2X antagonists assessed cytometric measurements ATP-induced ethidium+ uptake RPMI 8226 cells. Osmotic fragility lysis hypotonic saline. fractionated discontinuous density centrifugation. RESULTS ATP (1 mmol/L) induced for less than 1 week. This near-completely inhibited A438079 AZ10606120 P2X1/P2X7 antagonist MRS2159 not P2X1 NF499. dependent K+, Na+, Cl− fluxes. ATP did alter osmotic similar between different densities. also week 6 weeks. CONCLUSION The propensity undergo P2X7-mediated does vivo ex aging. Thus, activation unlikely be involved transfusion.