Biology of the human malignant lymphomas. III. Intracranial heterotransplantation in the nude, athymic mouse.

Intracranial heterotransplantation in the nude, athymic mouse has been found to be an effective method for the experimental growth of human malignant lymphomas. Transplants of 11 primary lymphomas and six derived cell lines yielded a high take rate (90%) and a low mean latent period (36 days). Relatively small inocula produced extensive intracerebral infiltrates which could be identified as human in origin by immunofluorescence. Although confined to the central nervous system and meninges, the tumors were highly invasive and displayed morphologic features strikingly similar to those of the original primary tumors. Heterotransplantation of the lymphomas to extracranial sites was only rarely successful. Nude mice previously grafted with isologous neonatal thymuses failed to develop intracerebral tumors. Secondary cell cultures successfully established from several of the intracranial heterotransplants were found to be infected with NIH type-C xenotropic virus. The distinctive growth patterns and other neuropathologic features of the heterotransplants are described, and the relevance of these observations to the development of intracerebral lymphomas in immunosuppressed organ transplant recipients is noted. This method of studying human malignant lymphomas in vivo may permit better histopathologic characterization of the tumors, and may serve as a basis for further experimental lines of investigation, including viral, immunologic, and therapeutic studies.