[Immunotherapy of Friend leukemia with antiserum (author's transl)].

Friend leukemia is caused by Friend leukemia virus (FLV) in susceptible mice. The malignant cells are of erythrocyte and lymphoid cell origin. Spleen enlargement could be detected within two weeks of FLV inoculation. The diseased mice usually die in the third or fourth month. Specific antisera were prepared from chimpanzee or rabbit by injection of FLV or FLV gp 71 in Freund's adjuvant. In the study of immunotherapy, DBA/2J mice were used. Normally, DBA/2J mice have an average spleen weight of 100 mg. After inoculation with FLV, the spleen enlarged to around 1,000 mg. Chimpanzee anti-FLV and chimpanzee anti-FLV gp 71 antisera were effective in treatment of FLV infection. The spleen enlargement could be recovered to normal range. The survival also was remarkably prolonged. Rabbit anti-FLV gp 71 antiserum was partially effective in retardation of spleen enlargement after FLV inoculation. On the contrary, 2 lots of rabbits anti-FLV antisera were found to accelerate spleen enlargement. Possibility of the presence of enhancement factor is considered. Therefore, different reactions in different species of animal to FLV vaccination are evident.