Unresponsiveness of antidonor cytotoxic T cells in a long-term stable renal transplant recipient.

The antidonor immune response was examined in a one haplotype-mismatched renal transplant recipient with an allograft that had been well-functioning for more than 10 years. Although the relative response of the mixed lymphocyte reaction (MLR) was (45.8)% and the MLR responder cells stimulated by donor cells produced measurable amounts of interleukin-2 (IL-2) (11.6 U/ml), the cytotoxic T lymphocytes (CTL) could not be generated against donor cells, even with exogenous IL-2. These results indicate that antidonor CTL precursors were either deleted or inactivated in this recipient.