ИСТИНА

We designed a novel bi-promoter vector harbouring CMV promoter/enhancer, EF-1 alpha promoter and different transcription terminators. The HC was placed downstream of EF-1 alpha promoter, but the antibody LC was driven by CMV promoter (in “head-to-head” (HH) and “head-to-tail” (HT) promoter orientation.) As control, HC and LC of antibodies were cloned separately into pOptiVEC and pcDNA 3.3 plasmids for co-transfection studies. This vector was used for the construction of a set of plasmids for the expression of a humanized antibody to TNF-alpha and a broadly neutralizing human antibody to influenza group A hemagglutinin. Comparison of antibody expr in case of transfection the bi-promoter plasmid and the co-transfection expression system after polyclonal selection (anti-hemagglutinin antibody) and after the MTX-induced gene amplification (anti-TNF-alpha antibody) demonstrated the 2-fold increase of antibody production after selection step and 2,8 - 3,2 – fold increase at the gene amplification. The bi-promoter vector system can be used for increasing the antibody production level at the early stage of cell line development. This work was supported by the Ministry of Science and Education of Russian Federation (Project identification number RFMEFI60714X0060).