LABORATORY IMMUNOLOGY - IMMUNE MONITORING AND MOLECULAR DIAGNOSIS

B.J.C. Näther
Department Of Nephrology, Charité Campus Mitte, Berlin/GERMANY

Body: Introduction: Immunosuppression minimization and tolerance induction require reliable in vitro assays for monitoring cellular alloimmunity in transplant patients. The IFN-γ ELISPOT assay could be a useful tool for monitoring alloreactive memory/ effector T cells. Methods: Peripheral blood mononuclear cells (PBMNC) of kidney transplant recipients were depleted of CD14+ and CD15+ cells to increase the percentage of T cells. The assay was used in a population of 27 de novo renal transplant patients and tested for clinical relevance. Before (pre-tx) and 2-3 times during the first 6 months after transplantation (post-tx) IFN-γ-producing donor-reactive T cell frequencies were determined. The outcome of patients getting grafts from deceased donors (n=19) was compared with patients receiving a living (related or unrelated, n=8) transplant. Results: From those 8 patients with living grafts it was possible to match 6 with a corresponding recipient of a transplant from a deceased donor. In 4 of 6 cases there was no difference in the strength of donor-reactive T cell frequency. The 6 months creatinine and 6 months glomerular filtration rate of recipients of kidneys from deceased donors and of those getting living transplants were on the same level. In 2 of 6 cases the recipients of organs from deceased donors showed even weaker mean alloresponses than the matched recipients of living grafts. Conclusion: Our results suggest that our modified donor-reactive ELISPOT test could be a reliable surrogate marker for renal transplant outcome. The preparation time of living transplantations would permit the running of the ELSPOT assay pre-tx in each patient. Therefore, in clinical use, determination of high donor-reactive responses pre-tx could guide the use of alternative living donors and identify high risk recipients for prophylactic aggressive immunosuppression. Additionally, our study has shown once more that kidney transplantation from deceased donors can achieve the same good results as that achieved with living transplantation.

Disclosure: All authors have declared no conflicts of interest.