Author Archives: Stephen F. Gorfien

Attaining Next-Level Titers in CHO Fed-Batch Cultures

    Taking full advantage of high cell-specific productivity of recombinant proteins requires use of robust fed-batch processes involving addition of one or more concentrated nutrient solutions. Proportionately large amounts of concentrated nutrient supplements are often needed to support the stoichiometrically balanced metabolic requirements of high-density cell cultures. Large feed additions ultimately dilute the final product at harvest, but attempts to minimize feed volumes often lead to multiple concentrated acidic and basic subgroups. Those impart additional complexity to manufacturing processes.…

Differential Cell Culture Media for Single-Cell Cloning

    Recombinant therapeutic protein production using cell culture systems is a US$70 billion market. Most biotherapeutic proteins, including monoclonal antibodies (MAbs), are produced in Chinese hamster ovary (CHO) cells, which can generate the posttranslational modifications required for full biological function. Single-cell cloning is an important step in generating homogenous recombinant protein-producing mammalian cell lines. Recent advances in media development technologies have enabled limiting dilution cloning (LDC) and protein production in a serum-free environment to meet regulatory requirements.   LDC…