A high density CHO-S transient transfection system: Comparison of ExpiCHO and Expi293.

Chinese Hamster Ovary (CHO) cells are the principal mammalian host used for stable cell line generation and biotherapeutic protein production. Until recently, production of milligrams to grams of protein in CHO transient systems was challenging. As such, Human Embryonic Kidney (HEK293) cells are the most common mammalian cell type used for transient transfection.

Scalable transient protein expression.

Transient transfection is a well-established method to rapidly express recombinant proteins from mammalian cells. Accelerating activity in biotherapeutic drug development, demand for protein-based reagents, vaccine research, and large initiatives in structural and functional studies of proteins have propelled the need to generate moderate to high amounts of recombinant proteins and other macromolecules in a flexible and rapid manner. Progress over the last 10-15 years has demonstrated that transient transfections can be reliably and readily scaled up to handle milliliters to tens of liters of cells in suspension culture and obtain milligrams to grams of recombinant protein in a process that requires only days to weeks.

Transient transfection factors for high-level recombinant protein production in suspension cultured mammalian cells.

The efficient transfection of cloned genes into mammalian cells system plays a critical role in the production of large quantities of recombinant proteins (r-proteins). In order to establish a simple and scaleable transient protein production system, we have used a cationic lipid-based transfection reagent-FreeStyle MAX to study transient transfection in serum-free suspension human embryonic kidney (HEK) 293 and Chinese hamster ovary (CHO) cells. We used quantification of green fluorescent protein (GFP) to monitor transfection efficiency and expression of a cloned human IgG antibody to monitor r-protein production.

Non-viral human IL-10 gene expression reduces acute rejection in heterotopic auxiliary liver transplantation in rats.

We studied nonviral delivery, expression, and the effect of the human interleukin-10 (Hu IL-10) gene on the rat model of heterotopic auxiliary liver transplantation (HALT). Two previous pilot studies showed remarkable expression of the Hu IL-10 gene in donor and recipient rats, and a decreasing effect of acute rejection in certain cases. In this study, we focused on the efficacy of Hu IL-10 gene expression to decrease acute rejection compared with cyclosporine A (CyA) in a HALT model.