EFFECTS OF RECOMBINANT INTERFERON-TAU ON OVINE LENTIVIRUS REPLICATION

As a pregnancy recognition signal, sheep trophoblast cells secrete a t ype I interferon, ovine interferon-tau (Ov-IFN-tau), which has potent antiviral activity, We studied the effects of a recombinant protein (r Ov-IFN-tau) on the replication of ovine lentivirus (OvLV) in goat syno vial membrane cells, The amount of provirus DNA, as measured by polyme rase chain reaction (PCR), the virus titers, and the number of OvLV-in duced syncytia were 76.5%, 82%, and 95%, respectively, lower in cultur es treated with rOv-IFN-tau than in placebo-treated controls (p < 0.01 ), rOv-IFN-tau also reduced OvLV reverse transcriptase activity and pr otected cells from OvLV-induced cell lysis, but the effect was less dr amatic, The antiviral activity increased with the concentration up to a maximum with 256 antiviral units of rOv-IFN-tau per ml.