Immunologic induction of malignant lymphoma: identification of donor and host tumors in the graft-versus-host model.

Primary lymphoid tumors were induced by inoculation of parental line spleen cells into H-2 incompatible F1 hybrid mice. The genotypes of lymphomas arising in 19 different parent yields F1 combinations were determined with cytotoxic antisera against H-2 specificities of donor and host. Additional chromosome marker studies established the reliability of tumor genotyping by the cytotoxicity test. According to H-2 typing, 12 primary lymphomas were of donor type, 66 of host type, and 14 of intermediate type. As a group, those parent yields F1 combinations in which donor-type lymphomas developed (group 1) showed a higher degree of histocompatibility between donor and host than those combinations in which donor-type lymphomas failed to appear (group 2). Allogeneic inhibition may have suppressed the development of donor-type tumors in the combinations of group 2. The development of malignant lymphomas of donor-type in the graft-versus-host reaction (GNHR) supports the concept of lymphomagenesis as a consequence of persistent stimulation by antigen.