Total CD8⁺and antigen-specific T cells from AIM patients are susceptible to apoptosis in vitro but can be rescued by cytokines. (A) Freshly isolated PBMCs from AIM patients or from those with previous history of AIM were cultured in complete culture medium for 5 days. Survival of total CD8⁺ and tetramer-positive CD8⁺ T cells was calculated as a percentage of the initial number of CD8 or tetramer-positive T cells present before culture. Mean ± SEM of triplicate determinations from 1 of 3 separate experiments with similar results are shown. (B) Survival of CD8⁺ and EBV-lytic, epitope-specific CD8⁺ T cells cultured in the presence or absence of IL-2, IL-15, or type 1 IFN for 24 hours was investigated. Mean ± SEM percentage survival of 3 separate experiments is shown. (C) Expression of Bcl-2, Bcl-x, and Bax mRNA levels were determined by RT-PCR, performed over a range of cycles. Representative blot shows the level of expression in freshly isolated CD4⁺ and CD8⁺ T cells from an AIM patient and the same CD8⁺ T cells cultured in the presence of IL-2 for 24 hours.