Generation of autologous Epstein-Barr virus-specific cytotoxic T cells foradoptive immunotherapy in solid organ transplant recipients

Background. Epstein-Barr virus (EBV)-driven posttransplant lymphoproliferat ive disorders (PTLD) affect 2%-27% of solid organ transplant (SOT) recipien ts. Adoptive immunotherapy may have therapeutic potential in this setting, but there is little experience in generating autologous EBV-specific cytoto xic T-cell lymphocytes (EBV-CTLs) from SOT recipients, and their efficacy a nd persistence in an immunosuppressed environment is unknown. Methods. EBV-CTLs were generated from eight SOT recipients. using weekly st imulations with autologous lymphoblastoid cell lines (LCLs) and interleukin -2. CTL phenotype and function were evaluated in the presence of therapeuti c concentration of cyclosporin A or FK506. Results. In all cases, CTLs expanded with normal kinetics. The majority was CD3+CD8+ (mean, 76%), with less than 3% of natural killer cells. All ex vi vo-generated CTLs produced significantly higher killing of autologous LCLs than of FILA-mismatched LCLs (mean, 56% vs. 14% at 20:1 ratio). No lysis of autologous or allogeneic PHA blasts was observed. The CTL expansion rate w as reduced in a concentration-dependent manner in the presence of immunosup pressive drugs; however, neither lytic activity nor phenotype was affected. Conclusions. Using methods that are approved for clinical application, EBV- CTLs can be generated from SOT recipients, even those with frank lymphoma, or who are receiving immunosuppressive drugs. These CTLs retain their funct ion in the presence of immunosuppressive agents. Although in vivo efficacy, safety, and persistence can be assessed only in clinical trials, our resul ts suggest that CTLs can be effective for the treatment of PTLD, even when immunosuppression cannot be reduced because of the high risk of graft rejec tion.