Author Archives: Steven P. Allen

Expression of Recombinant Antibody Fragments: High-Density Fermentation in Multiuse and Single-Use Systems

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Single-use fermentors (SUFs) offer dramatic advantages over traditional stainless-steel clean-in-place (CIP)/sterilization-in-place (SIP) fermentors. Single-use technology eliminates the need for steam, chemicals, and water to clean and sterilize stainless vessels, which provides a direct reduction in capital cost and environmental-impact mitigation. Single-use platforms also increase equipment and process flexibility significantly, making it possible to switch campaigns from one product to another in minimal time, while eliminating cleaning and associated validation steps (1). Both Cytiva and Thermo Fisher Scientific offer SUFs that…

February 9, 2022

Oxygen Control Strategy and Yield of Recombinant Antibody Fragments Produced in Fermentation

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Immunoglobulin molecules are used extensively in therapeutic treatments, diagnostic applications, and fundamental academic research. Traditionally, full-length antibodies and smaller fragments such as the recombinant antigen-binding fragment (rFab) are produced through mammalian cell culture. rFabs also are small enough to be produced in Escherichia coli through fermentation (1, 2). Because disulfide bonds cannot be formed efficiently in the reducing cytoplasm of E. coli, rFabs are supplemented most commonly with a signal sequence that directs them to the more oxidizing bacterial periplasm…

February 4, 2021

Optimization and Scale-Up of HCIC-Based MAb Purification Processes, Part 2

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In multistep schemes, hydrophobic charge-induction chromatography (HCIC) has been shown to contribute effectively to clearance of Chinese hamster ovary (CHO) host-cell proteins (CHOPs), DNA, and viruses. When used for capture chromatography, HCIC can provide better aggregate clearance than protein A sorbents can. Chen et al. enhanced clearance of aggregates, CHOPs, and product- related impurities by controlling HCIC based on both pH and the presence of binding-promoting salt in the wash and elution buffers used (1). Taken together with our findings…

June 16, 2015

Optimization and Scale-Up of HCIC-Based MAb Purification Processes, Part 1

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Monoclonal antibodies (MAbs) serve important medical needs in cancer treatment as well as that of autoimmune and infectious diseases (1). Antibodies are also widely used in clinical diagnostic assays. They can be coated on solid surfaces to bind specific analytes, conjugated to reporter molecules (either as whole antibodies or fragments) for analyte detection, used in sensitivity panels for lot-release testing, and supplied as positive controls in diagnostic kits (2). Our study evaluates the use of hydrophobic charge-induction chromatography (HCIC) for…

May 12, 2015