ExpreS2ion Biotechnologies The company is a world leading biotech company within protein production in Drosophila Schneider-2 (S2) cells. S2 cell have been used for recombinant protein production for several decades, including for production of clinical lots. The S2 platform is robust, scalable from lab bench to cGMP production, and regulatory friendly. The company has a proprietary Drosophila S2 technology platform that was developed over ten years. The company offers recombinant protein production services and licenses to the ExpreS2 platform.