[Xenotransplantation of established tumor cells in congenital thymusless "nude" mice (author's transl)].

Successful xenotransplantation of 5 different established tumor cell-lines was performed in the congenital thymusless mouse mutant "nude". The tumors were one human carcinoma of the cervix (HeLa), one Burkitt's lymphoma as well as two Polyoma virus-induced tumors from rats and one spontaneous tumor from hamster. During an observation period of 21-28 days all cells formed rapidly growing tumors at the injection site. The critical cell dose varied in the different lines between 10-4 and 10-6 cells. Histological appearance of the neoplasias resembled that of the primary tumors. Two established lines from normal fibroblasts (3-T-3) and kidney (CV-1) failed to grow. Our results indicate that xenotransplantation in "nude" mice may serve as a simple in-vivo assay for testing the oncogenicity of tissue culture cells.