Low dose total body irradiation: a potent anti-retroviral agent in vivo.

Immunosuppression characterizes many human diseases including leukemia and AIDS. Friend virus (FV)-induced murine leukemia is a useful model for studying both malignancy and immunosuppression. In a previous series of experiments, we have demonstrated that untreated FV-infected mice died within 40 days post-infection, whereas infected mice given 150 cGy total body irradiation (TBI) on days 5 and 12 exhibited long-term survival. In this report, we show that no leukemic cells or type C virus particles are found in the spleens of mice treated with TBI. In addition, both NK activity as well as bone marrow cell's proliferative responses to PHA and Con A were fully restored. This treatment produces long term control of FV-induced murine leukemia, and thus might have relevance for the treatment of a number of immunosuppressive diseases including AIDS.