Deficiency in Epstein-Ban- Virus Receptors on B-Lymphocytes of Preleukemia Patients1

Lymphocytes from eight preleukemia patients were exposed to Epstein-Barr virus (EBV) in vitro in an attempt to establish lymphoblastoid cell lines. No signs of viral infection were de tected, and no cell lines were obtained. Studies using fluoresceinlabeled EBV and flow cytometry revealed an unusual and con sistent deficiency in EBV receptors in all patients examined. In control studies, about 15% of the unseparated lymphocytes from healthy donors bound fluorescein-labeled EBV. In spite of the lack of EBV receptors, B-lymphocytes amounted to 10 to 20% of the preleukemia lymphocyte populations, a proportion similar to that in healthy donors. When lymphocytes from preleukemic patients were first implanted with functional EBV receptors and then exposed to EBV, synthesis of EBV-determined nuclear, early, and viral capsid antigens was induced. Subsequently, several cell lines originating from preleukemic patients' lympho cytes were established. These lines are of a B-lymphocyte origin and carry EBV genome. They will provide experimental material for the molecular analysis of lymphocytic defects in preleukemia and their possible role in the transition to acute leukemia.