Rebound effect of the allogenic T-cell response to donor and third-party lymphocytes after cyclosporine withdrawal in renal transplant recipients

Mixed lymphocyte reaction (MLR) assays were performed serially over 24 months in 19 first cadaver renal transplant recipients. Immunosuppression consisted of cyclosporine, methylprednisolone and azathioprine. Cyclosporine was withdrawn at 6 months postoperatively. The MLR reactivity gradually decreased over the first 3 months following transplantation. However, there was a significant increase in MLR reactivity at 12 months postoperatively after the cyclosporine withdrawal. This rebound effect in MLR reactivity following cyclosporine withdrawal could account for the increased incidence of acute rejection episodes.