Recombinant TNF and recombinant IFN-G have been shown to be effective against the virus which causes AIDS and ARC in some laboratory studies, but may increase virus replication in other laboratory studies. Previous studies in humans showed no increase in virus cultures and some decrease in measurements of virus. Extensive preclinical data show that TNF and IFN-G are more effective together than separately in laboratory and animal studies. As single agents, both TNF and IFN-G have modest effect against HIV. Studies have demonstrated that TNF and IFN-G, in combination, can not only inhibit HIV infection of previously uninfected cells, but also can selectively induce the destruction of acutely infected target cells.