High Yield Expression and Secretion of the Ovine Pregnancy Recognition Hormone Interferon-τ by Pichia pastoris

The early conceptus (embryo and associated membranes) of domestic ruminants signals its presence to the maternal uterus through production of interferon-τ (IFN-τ). Production of IFN-τ ensures continued production of progesterone, the hormone of pregnancy, by the ovarian corpus luteum. This paper reports the high-level expression and efficient secretion of biologically active recombinant ovine IFN-τ (rOvIFN-τ) by Pichia pastoris. The developed method produces more than 80% pure recombinant ovine IFN-τ, obviating the need for further purification for many purposes. Initial fermentation studies produced IFN-τ at 280 mg/liter and demonstrate the potential of this system for large-scale production of IFN-τ.