RELEVANCE OF PRETRANSPLANT DONOR-SPECIFIC T-CELL ALLOREPERTOIRE FOR HUMAN KIDNEY GRAFT-SURVIVAL

In order to determine whether the donor-specific T cell allorepertoire evaluated in patients before transplantation can be predictive for ki dney graft survival, a study has been set up in which the number and a ctivation state of donor-specific T lymphocytes before transplantation were correlated to transplant survival time. Limiting dilution analys is assays were carried out to determine precursor frequencies of both T helper and cytotoxic T lymphocytes. The activation state of these ce lls was studied by evaluating the inhibitory capacity of cyclosporine on helper and cytotoxic T cells and/or a monoclonal antibody directed against CD8 on cytotoxic T cells. This study shows that neither a sign ificant difference in the number nor activation state of donor-directe d helper and cytotoxic T cells before transplantation could be detecte d when patients who acutely rejected their grafts were compared with p atients who still had a well-functioning kidney graft after more than 10 years. Moreover, no significant differences in the donor-specific T cell repertoire were found when patients who had been subject to mult iple rejection episodes were compared with patients who experienced fe w complications after transplantation. Therefore, we conclude that in individuals who have not been sensitized to HLA antigens of the donor, the donor-specific peripheral T cell allorepertoire prior to transpla ntation is not predictive of kidney graft survival.