Therapeutic monoclonal antibodies (mAbs) are produced via a laborious multi-step process involving cell line development (CLD), antibody purification, and extensive testing. Although this approach has proven to be effective, as evidenced by the number of mAb therapeutics to reach the market, it has a high associated risk of failure and is often unsuitable for poorly immunogenic targets. As a result, researchers are choosing to incorporate state-of-the-art technologies for rapid identification, characterization, and purification of candidate molecules into mAb development workflows to increase their chances of discovering the next novel drug.
mAbs are one of the fastest-growing classes of biopharmaceuticals, being used to treat conditions spanning cancer to autoimmune disease. To date, over 100 mAbs have been approved by the U.S. Food and Drug Administration (FDA) and more than 400 mAbs are currently undergoing clinical evaluation. However, while the majority of approved mAbs target cell surface or single-pass membrane proteins, the development of mAbs targeting less immunogenic multi-pass membrane proteins such as G protein-coupled receptors (GPCRs) has lagged behind. Addressing this disparity requires the use of innovative high-throughput cell screening and protein production methods to bring urgently needed therapeutics to patients.
Cell line development is one of the earliest stages in the mAb development process, which aims to generate and validate stable, high-titer cell lines that can be readily scaled. It begins with gene cloning and rapid screening of cell mini-pools to assess titer, cell health, and cell growth, followed by a more comprehensive analysis of selected, high-productivity clones to confirm critical quality attributes (CQAs) and target specificities. Next, culture conditions and media formulations for optimal growth and protein production must be identified and the best-performing clones evaluated for stability, productivity, and CQAs of the secreted antibody.
Sartoclear Dynamics® Lab performs rapid, one-step clarification and filtration of cell culture media.
Once the successful cell lines have been banked, it is necessary to optimize the conditions for antibody purification. Key steps to consider include cell clarification and filtration, antibody capture by affinity chromatography, and purification, as well as concentration and sterile filtration, all of which have the potential to influence antibody yield and quality. For example, contaminating artifacts such as host cell proteins (HCPs) and DNA can be present in varying abundance depending on the cell type and culture conditions, and must be removed from the final product to ensure patient safety.
Critically, by applying process optimization throughout CLD and antibody purification workflows, it is possible to both save time and reduce costs.
A broad range of tools and technologies is now available to streamline mAb development. For faster screening, selection, and isolation of individual clones, researchers can replace manual workflows with automated single-cell picking. And for more efficient evaluation of cellular phenotype and function, advanced flow cytometry systems have been developed that provide high content information using as little as 5 µL sample in a 384-well plate. Other options for CLD include live cell analysis systems for real-time monitoring of the kinetic effects of antibody treatment on target cells, and label-free biomolecular interaction analysis platforms for rapid affinity ranking and epitope binning of antibody matrices.
Antibody purification workflows have likewise been improved with innovative solutions covering every stage of the process. To separate antibody-containing supernatant from cells, cellular debris, and other artifacts, various kits have been developed that enable clarification and sterile filtration to be performed in a single step. For simpler antibody enrichment compared to using traditional resin-based ion exchange or affinity chromatography methods, Protein A affinity membrane chromatography delivers high yields and is easily transferred to manufacturing. And for antibody concentration purposes, it is now possible to perform tangential flow filtration (TFF), also known as cross-flow filtration, in place of conventional centrifugation methods to provide the highest target recoveries. Importantly, a wide variety of membrane materials and molecular weight cut-offs (MWCOs) is now available for concentrating and purifying antibodies to prevent protein loss while ensuring maximum processing speeds.
Sartorius offers a wide array of lab essentials for cell line development and antibody purification, including Sartoclear Dynamics® Kits for rapid, one-step clarification and filtration of cell culture media. To learn more, visit sartorius.com.