Influence of culture conditions on recombinant Drosophila melanogaster S2 cells producing rabies virus glycoprotein cultivated in serum-free medium

The recombinant G glycoprotein from the surface of the rabies virus (RVGP) is a promising candidate as a rabies vaccine component and also for diagnostic purposes. In this study, RVGP production by transfected Drosophila melanogaster S2 cells cultivated in a serum-free medium (Supplemented IPL-41 medium) was carried out. The effects of pH and pO(2) were evaluated in batch culture in parallel spinner flasks. The use of a pH equal to 6.3 and a pO(2) of 40% air saturation resulted in the highest RVGP content. These conditions were also used in fed-batch mode, yielding a RVGP content level of 98 g/10(7) cells. The main nutrients consumed were glucose, glutamine, asparagine, serine and proline and the major metabolites produced were alanine and ammonia, according to the metabolism studies performed. Since RVGP is a transmembrane protein, two different methods for protein recovery were assessed and compared. Detergent-based cell disruption showed to be more effective than mechanical disruption with glass beads for glycoprotein recovery. (C) 2008 The International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.