Anergic T cells are alloantigen-specific.

(A) Control or hyporesponsive T cells (2 × 10⁴) were restimulated with 1 × 105 specific or third-party stimulator PBMCs that were either completely mismatched or partially matched, ie, in this case, DRB1*0401 (DR4) and B*4901 (B49). (B) IL-2 restored the proliferative response of anergic T cells solely when antigenic restimulation was performed with the specific stimulator PBMCs or the third-party stimulator PBMCs with a shared DR type. Results show the mean ³H incorporation and SE of quadruplicate measurements on day 3 of culture. (C) The cytotoxic response is HLA class I specific. Specific lysis (E/T = 100) is shown against allogeneic target cells, which are either completely mismatched (white bars) or shared MHC antigens (crossed bars) against which the responder cells were generated (here B49 and DR4). Results are expressed as the percentage of specific lysis. Representative experiments are shown.