Abstract
Lymphoblasts appearing in immunosuppressed patients after bone marrow transfusion are compared to those that can be established in vitro as permanent lymphoid cell lines. It is suggested that Epstein-Barr virus (EBV) could be responsible for the recurrent "lymphoblastic leukemia" in these patients and that the transplanted cells may be a clone of nonmalignant cells that has become capable of growing without normal restraints. It is important that in future patients the transplanted cells be characterized as to morphology, chromosome constitution, relative clonability and transplantability, the presence of EBV, T or B cell-like traits, and their growth potential in immunosuppressed heterologous hosts. The antibody titer to EBV should be measured before and after leukocyte transfusion.
