ANTI-HIV POTENTIAL OF A NEW INTERFERON, INTERFERON-TAU (TROPHOBLASTIN)

Antiretroviral effects of a new class of interferon (IFN), IFN-tau, we re compared with those of IFN-alpha in primary peripheral blood lympho cytes (PBLs) and monocyte-derived macrophages (MDMs), infected in vitr o by human immunodeficiency viruses type 1, HIV-1/LAI, and HIV-1/DAS i solates, respectively. Cells were treated with recombinant IFN 24 h be fore or after HIV infection and then continuously exposed. Viral repli cation was monitored twice a week by quantifying the reverse transcrip tase activity in cell culture supernatants. Integrated proviral DNA wa s monitored 24 h after infection in IFN-tau-pretreated MDMs, using spe cific gag gene amplification by the polymerase chain reaction. IFN-tau inhibited HIV-1 replication in both PBLs and MDMs as well as in perip heral blood mononuclear cells (PBMCs). IFN-tau was 35-fold more potent than IFN-alpha in PBLs and 100-fold more potent in MDMs. Differences were observed in the amount of integrated proviral DNA between untreat ed and 10 IU/ml IFN-tau-treated HIV-infected MDMs. IFN-tau exhibits si gnificant anti-HIV activity in comparison to IFN-alpha, and like other IFNs, it seems to interact with several steps of HIV replication cycl e.