Regulatory T cell subtypes and TGF-β1 gene expression in chronic allograft dysfunction

Regulatory T cells have been suggested to have a protective role against acute rejection in allograft recipients. However, there is little information available about their contribution to chronic rejection process. The role of transforming growth factor-beta 1 (TGF-β1) as a profibrogenic and/or immunoregulatory cytokine in renal allografts is also controversial. To evaluate the frequency of CD4+CD25+CD127- and CD3+CD8+CD28- regulatory T cells in chronic allograft dysfunction (CAD) and to investigate the expression of TGF-β1 in renal allografts. Thirty biopsy-proven CAD patients were pair-matched with 30 stable graft function patients and a third group of healthy volunteers. Flowcytometry was performed on PBMCs to determine the frequency of CD3+CD8+CD28- and CD4+CD25+CD127- regulatory T cells in lymphocyt population. TGF-β1 gene expression was assessed by Real Time PCR. The percentages of CD3+CD8+CD28- Tregs among renal allograft recipients was higher than healthy controls (p