Impairment of T-cell control of Epstein-Barr virus infected B-cells in patients with adult T-cell leukemia.

The abilities of peripheral blood lymphocytes from 9 patients with adult T-cell leukemia (ATL) and 14 healthy control adults to cause regression of proliferating B-cell foci induced by Epstein-Barr virus (EBV) were examined. Marked regression of EBV-transformed B-cell foci was observed in lymphocytes from all 10 EBV-seropositive donors but with none of those of the 4 EBV-seronegative donors in the control group. The lymphocyte of all 9 patients with ATL, who were EBV-seropositive, caused little or no regression of B-cell foci like those of EBV-negative healthy donors. These results suggest that the absence of regression of EBV-induced B-cell proliferation observed in ATL patients is due to impairment of EBV-specific killer T-cell activities.