Background: Adoptive immunotherapy with autologous and donor-derived cytotoxic T lymphocytes (CTL) has recently been used to treat Epstein Barr virus (EBV)-positive posttransplant lymphoproliferative disease (PTLD).
Methods and results: We report complete regression of EBV-positive PTLD in an 18-month-old small bowel and liver transplant recipient after one infusion of partially human leukocyte antigen (HLA)-matched EBV-specific CTL grown ex vivo from an EBV seropositive unrelated blood donor. No infusion-related toxicity or evidence of graft-versus-host disease was observed. The tumor showed signs of regression within 1 week and EBV load in peripheral blood dropped to undetectable levels. Limiting dilution analyses (LDA) detected no EBV-specific CTL precursor (CTLp) cells before the infusion, and high numbers of CTLp at 4 hr and 24 hr post-CTL infusion. There was a reversal of the CD4/8 ratio in peripheral blood and an increase in HLA-DR positive CD8 cells. The patient has been in complete remission for 24 months.
Conclusion: If this success is repeated in more PTLD patients, then stored CTL could be used for antiviral and antitumor therapies in immunocompromised patients.