The Purinergic Receptor Antagonist Oxidized Adenosine Triphosphate Promotes Corneal Allograft Survival Without Expanding Regulatory T Cells

Purpose: Adenosine triphosphate (ATP) is released into the extracellular environment during transplantation, and acts via purinergic receptors to amplify the alloimmune response. The purpose of our study was to investigate the immunomodulatory mechanisms of the purinergic receptor antagonist oxidized ATP (oATP) in a murine model of corneal allotransplantation.Methods: Allogeneic corneal transplantation was performed using 6-8 week-old C57BL/6 donors and BALB/c hosts. oATP was administered via intraperitoneal injection (250 μg) once daily for 14 days post-operatively. The control group received intraperitoneal injections of sterile saline. Single cell suspensions of corneal tissue and draining lymph nodes were prepared at 14 days post-transplantation, and frequencies of CD45+ leukocytes, CD11b+ MHCII+ antigen presenting cells (APCs), CD4+ IFN-γ+ effector Th1 cells and CD4+ Foxp3+ regulatory T …