Expression of human PAI-2 in the baculovirus expression system

Using pSXIVVI⁺X3 as an expressing vector, an occluded recombinant Trichoplusia ni nuclear polyhedrosis virus carrying the cDNA encoding plasminogen activators inhibitor-2 (PAI-2) under the control of the Syn and XIV promoters, has been constructed. SDS-PAGE and immunoblot analysis revealed that the virus-mediated PAI-2, with a molecular weight of ∼45 kDa, was synthesized in the Sf cells at a level of ∼16% of total intracellular protein and in the supernatant phase at a level of ∼64% of total extracellular protein secreted into the hemolymph of infected larvae. The expressed protein was similar to its authentic counterpart in terms of immunoreactivity and bioactivity. Received 5 May 1998/ Accepted in revised form 15 July 1998