Dynamic Changes of IFN-γ-producing Cells, TGF-β and Their Predictive Value in Early Outcomes of Renal Transplantation

Background: A growing body of evidence demonstrated an immune etiology as well as nonimmune mechanismsfor episodes of clinical acute rejection and long-term allograft dysfunction.Objective: To investigate the correlation of IFN-γ-producing cells and TGF-β with incidence of clinical acuterejection in living-related and unrelated kidney allogarft recipients during the first post-transplant year.Methods: This multi-center study was performed on 57 kidney allograft recipients from living-related(n=20) and unrelated (n=37) donors between April 2011 and September 2012 and who were followedprospectively for a mean period of one year. Peripheral blood samples were collected from all patientspre-transplantation and at days 14, 30 and 90 after transplantation; PBMCs were used as responding cellsin enzyme-linked immunosorbent spot (ELISPOT) assay to measure the frequency of IFN-γ-producingcells after stimulation with donor lymphocytes. Additionally, TGF-β levels were measured in cell culturesupernatants of ELISPOT assay.Results: During the follow-up period, 45 (79%) patients were diagnosed with stable graft function (groupA); 12 (21%) experienced clinical acute rejection episodes (group B). The frequency of IFN-γ-producingcells was significantly (p<0.001) higher in the rejection group in all three times after transplantation.Also, post-transplantation comparison for TGF-β showed a significantly (p