Production of functional antibodies generated in a nonlytic insect cell expression system

A monoclonal antibody directed against the type 2 adenovirus (Ad2) penton b ase protein was cloned and expressed in Spodoptera frugiperda (Sf9) cells u sing a nonlytic vector system. The coding sequences for the immunoglobulin light and heavy chains were placed under the control of the Orgyia pseudots ugata multicapsid nucleopolyhedrosis virus immediate-early 2 (OpIE2) promot er. Transfected Sf9 cells continuously secreted the antibody which retained the ability to recognize both native and recombinant Ad2 penton base prote ins. Bifunctional penton base antibodies were also generated by fusing a ge ne for a growth factor or a cytokine at the 3' end of the Ig constant heavy chain domain, The quantity and activity of recombinant antibodies generate d in the nonlytic insect cell system could be determined relatively quickly compared to other expression systems. Moreover, these recombinant proteins were not subjected to proteolytic degradation as frequently occurs during baculovirus-mediated cell lysis and the levels of recombinant antibodies pr oduced in the nonlytic system were comparable to those reported for cytolyt ic baculovirus vectors. (C) 2001 Academic Press.