The growth of human HIV-1 infected U937 cells in immune-deprived mice

We report in vivo growth of human promonocytic cells infected with HIV-1 presented in new mouse model. Cloned U937 cells chronically infected with HIV-1 were grafted in (CBA*C57B1/6)F1 mice deprived of immunity by thymectomia and total body irradiation with subsequent marrow reconstitution. Nine weeks after cell inoculation, HIV-1-positive cells were found only in mice that received an additional single dose of cyclophosphamide (100 mg/kg bw) prior to transplantation, whereas, in mice without further immune deprivation, the complete elimination of cells bearing viral antigen occured already on the seventh day after transplantation. The approach described may be suitable for in vivo development of antiviral drugs against latent infection in macrophage-like cells which represents a serious problem in therapy of AIDS in humans