Author Archives: Bing Hu

Direct Analysis of Bioreactor Harvest for Clone Selection and Process Optimization

Therapeutic monoclonal antibodies (MAbs) mostly are manufactured using bioengineered mammalian cells cultured in a bioreactor for two to three weeks. High temperatures and an altered redox environment may compromise the quality of MAbs produced (e.g., fragmentation, truncation), as can the presence of proteases, reductases, and other chemicals released from dead cells. Thus, it would be valuable to establish analytical methods that can help cell culture groups monitor immunoglobulin G (IgG) product integrity in real time during a bioreactor run, especially…

eBook: Addressing Quality in Cell-Line Development — Direct Analysis of Bioreactor Harvest for Clone Selection and Process Optimization

Using Direct Analysis of Bioreactor Harvest for Clone Selection and Process Optimization Therapeutic monoclonal antibodies (MAbs) mostly are manufactured using bioengineered mammalian cells cultured in a bioreactor for two to three weeks. High temperatures and an altered redox environment may compromise the quality of MAbs produced (e.g., fragmentation, truncation), as can the presence of proteases, reductases, and other chemicals released from dead cells. Thus, it would be valuable to establish analytical methods that can help cell culture groups monitor immunoglobulin…

Residual Host-Cell DNA in Biopharmaceutical Products: 96-Well Plate-Based Extraction and Real-Time PCR Assay for Quantitative Measurement

Regulatory guidelines that cover the development of biopharmaceutical products require testing of host-cell deoxyribonucleic acid (DNA) impurities. Real-time polymerase chain reaction (PCR) has become a popular technology for DNA quantitation and monitoring of process impurities associated with biomanufacturing. One critical challenge associated with host-cell DNA impurity testing is that recombinant proteins (e.g., monoclonal antibodies, MAbs) and their corresponding buffer components often interfere with DNA quantitation in real-time PCR reactions (1, 2). Some sample types do not require a full extraction…

Development of an In-House, Process-Specific ELISA for Detecting HCP in a Therapeutic Antibody, Part 2

    During biopharmaceutical manufacturing, final drug products can get contaminated with host-cell proteins (HCPs) derived from a production cell line. HCPs can elicit adverse immune responses, so regulatory authorities require accurate monitoring of their presence and concentration in final drug products. Because they are robust and offer good throughput, enzyme-linked immunosorbent assays (ELISAs) are the first choice for HCP detection to monitor product quality. Generic ELISA kits are commercially available for HCP detection with a number of commonly used…

Development of an In-House, Process-Specific ELISA for Detecting HCP in a Therapeutic Antibody, Part 1

    After production and purification of biopharmaceuticals generated by cell culture expression systems, endogenous cell line proteins — commonly referred to as host-cell proteins (HCPs) — sometimes contaminate finished products. HCPs can elicit an immune response following administration of those drugs to patients (1), and cause potentially deleterious side effects. It is therefore imperative to minimize HCP contamination in finished biologics. Regulatory health authorities require monitoring of HCP contamination. They expect validation of each purification process to demonstrate its…