Enhanced production of interferon-gamma by T lymphocytes cloned from rejected kidney grafts.

Seventy-seven T cell clones were generated from cell blasts infiltrating rejected kidney allografts. All clones, either CD4 or CD8, displayed cytolytic activity evaluated by lectin-dependent cell-mediated cytotoxicity (LDCC) and natural killer activities. Furthermore, both types of clones were able to produce IFN-gamma following PHA stimulation. These data suggest that the graft infiltrate is characterized by T cell clones with cytolytic potential responsible for the killing of graft cells. The production of IFN-gamma, enhancing the class II MHC expression, may amplify the recipient immune response.