EVIDENCE FOR TRANSFORMATION OF SPLEEN CELLS ONE DAY AFTER INFECTION OF MICE WITH FRIEND LEUKEMIA VIRUS

Abstract
Proliferation and erythroid differentiation of transplanted DBA/2 marrow cells and Friend virus-induced leukemic cells were assessed in syngeneic, allogeneic (H-2 compatible), and (BALB/c x DBA/2)F1 hybrid mice (CDF1). Measurements were made 5 days after transplantation of donor cells into nonirradiated or X-irradiated mice by the spleen colony or the 125IUdR-59Fe uptake methods. Growth of DBA/2J (Jackson subline) marrow grafts was poor in irradiated CDF1J hybrids as compared with growth in syngeneic and allogeneic hosts. The DBA/2J transplants proliferated, however, without impairment in irradiated CDF1 hybrids which were the progeny of DBA/2 male parents of other sublines, e.g. DBA/2Ha, DBA/2Cr, and DBA/2Cum. In contrast, tissue-cultured Friend leukemic cells of DBA/2J origin grew deficiently in all CDF1 hybrids tested, regardless of irradiation and of the DBA/2 parent's subline. The growth pattern of transplanted DBA/2J cells was a manifestation of hybrid resistance. The results with DBA/2J and other DBA/2 subline grafts suggested that hybrid histocompatibility alleles were expressed to a greater extent in leukemic than in normal marrow cells, for the former were consistently recognized as "nonself" by CDF1 mice, but not the latter cells.