Evaluation of Recombinant Antibody Production Efficiency in CHO Cells with Sleeping Beauty Transposon Vector System

Chinese hamster ovary (CHO) mammalian cell lines are widely used as cell platforms in biopharmaceutical productions. Different transfection systems are employed for the integration of the target gene cassette into the cell genome and have limitations, such as (i) the integration region in the genome, (ii) the size of the target cassette, and (iii) long selection periods for stable expression. Transposon systems can be utilized to overcome the limitations mentioned in the efficient production of commercially significant recombinant proteins. This study aims to demonstrate the differences in production potential and selection periods by using a specially designed vector system for random genome integration in CHODG44 DHFR -/- cells and the Sleeping Beauty (SB) transposon system. In this context, the optimal transfer ratio between the donor and the helper plasmid was determined for the most efficient co-transfection in the SB transposon system. According to the results, the pools obtained using the SB transposon system had titers ranging from 1300 to 2600 mg/L in 13-day fed-batch studies, while the pool obtained using the random transfer system had a titer of 0.056 mg/L. Additionally, stable cell pools obtained using the transposon system underwent selection in a short period of 52 days, compared to over 100 days for the pool obtained through random transfer. Considering all these results together, it is demonstrated that stable CHO pools obtained using the optimal SB transposon system can achieve high-efficiency monoclonal antibody production in a short period, making it an optimal production platform in the biopharmaceutical field.