INFUSION OF CYTOTOXIC T-CELLS FOR THE PREVENTION AND TREATMENT OF EPSTEIN-BARR VIRUS-INDUCED LYMPHOMA IN ALLOGENEIC TRANSPLANT RECIPIENTS

Epstein-Barr virus (EBV) causes potentially lethal immunoblastic lymph oma in up to 25% of children receiving bone marrow transplants from un related or HLA-mismatched donors. Because this complication appears to stem from a deficiency of EBV-specific cytotoxic T cells, we assessed the safety and efficacy of donor-derived polyclonal (CD4(+) and CD8()) T-cell lines as immunoprophylaxis and treatment for EBV-related lym phoma. Thirty-nine patients considered to be at high risk for EBV-indu ced lymphoma each received 2 to 4 intravenous infusions of donor-deriv ed EBV-specific T lymphocytes, after they had received T-cell-depleted bone marrow from HLA-matched unrelated donors (n = 33) or mismatched family members (n = 6). The immunologic effects of this therapy were m onitored during and after the infusions. Infused cells were identified by detection of the neo marker gene. EBV-specific T cells bearing the neo marker were identified in all but 1 of the patients. serial analy sis of DNA detected the marker gene for as long as 18 weeks in unmanip ulated peripheral blood mononuclear cells and for as long as 38 months in regenerated lines of EBV-specific cytotoxic T cells. Six patients (15.5%) had greatly increased amounts of EBV-DNA on study entry (> 2,0 00 genome copies/10(6) mononuclear cells), indicating uncontrolled EBV replication, a complication that has had a high correlation with subs equent development of overt lymphoma. All of these patients showed 2 t o 4 log decreases in viral DNA levels within 2 to 3 weeks after infusi on and none developed lymphoma, confirming the antiviral activity of t he donor-derived cells. There were no toxic effects that could be attr ibuted to prophylactic T-cell therapy. Two additional patients who did not receive prophylaxis and developed overt immunoblastic lymphoma re sponded fully to T-cell infusion. Polyclonal donor-derived T-ceIl line s specific for EBV proteins can thus be used safely to prevent EBV-rel ated immunoblastic lymphoma after allogeneic marrow transplantation an d may also be effective in the treatment of established disease. (C) 1 998 by The American Society of Hematology.