Origin of lymphoid lines established from mixed cultures of cord-blood lymphocytes and explants from infectious mononucleosis, Burkitt lymphoma and healthy donors.

Lymphocytes were explanted from EBV-seropositive donors including peripheral blood of infectious mononucleosis patients, healthy donors and EBV-genome-carrying cells from Burkitt lymphoma (BL) biopsies or nude mouse-passaged, BL-biopsy-derived lines. The explanted cells were mixed with fresh cord-blood lymphocytes from mice of the opposite sex. In all categories of derived lines, cord-blood cell progeny was predominant, as judged by the sex marker and other associated markers. Only one BL biopsy line, serially passaged in nude mice, gave rise to a monoclonal lymphoma line.