Increased frequency of CD4+CD25highCD127lowT cells early after lung transplant is associated with improved graft survival – a retrospective study

Abstract

In this retrospective study, we analyzed the presence of any association of three CD4+ CD25high regulatory T-cell subpopulations at 3weeks after lung transplantation with the later incidence of chronic lung allograft dysfunction and graft survival. Among lung-transplanted patients between January 2009 and April 2018, only patients with sufficient T-cell measurements at 3weeks after transplantation were included into the study. Putative regulatory T cells were defined as CD4+ CD25high T cells, detected in peripheral blood and further analyzed for CD127low , FoxP3+ , and CD152+ using fluorescence-activated cell sorting (FACS) analysis. Associations of regulatory T cells with chronic lung allograft dysfunction (CLAD) and graft survival were evaluated using Cox analysis. During the study period, 724 (71%) patients were included into the study. Freedom from chronic lung allograft dysfunction (CLAD) and graft survival amounted to 66% and 68% at 5years. At the multivariable analysis, increasing frequencies of CD127low were associated with better freedom from CLAD (hazard ratio for each 1% increase of %CD127low , HR=0.989, 95% CI=0.981-0.996, P=0.003) and better graft survival (HR=0.991, 95% CI=0.984-0.999, P=0.026). A higher frequency of CD127low regulatory T cells in peripheral blood early after lung transplantation estimated a protective effect against chronic lung allograft dysfunction, mortality, and re-transplantation.