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Robustness, reliability and proven track-records to advance biotherapeutic programs

The CHOSOURCE™ Glutamine Sythetase (GS) knockout (KO) cell line is a well-established, cGMP-manufactured CHO-K1 suspension cell line, specifically engineered using precise rAAV technology to knock-out the glutamine synthetase gene to provide a robust industry standard selection system.

Since its introduction in 2016, this cell line has been adopted by over 100 users globally, leading to more than 60 regulatory filings submitted worldwide since 2018.

The performance of the CHOSOURCE GS KO cell line has been tested under different conditions such as diverse feeds, media, processes, molecules, and vector technologies, demonstrating unparalleled adaptability and flexibility. With its proven performance, the CHOSOURCE GS KO cell line comes with a comprehensive cell history package and protocols to support the entire biotherapeutic journey: from research and development to regulatory filing. CHOSOURCE GS KO has been designed to combine a flexible and cost-effective pricing structure without compromising on quality to meet specific customer needs. 

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