Assays

Nucleic Acid Impurity Reduction in Viral Vaccine Manufacturing

Commercial-scale viral vaccine manufacturing requires production of large quantities of virus as an antigenic source. To deliver those quantities, a number of systems are used for viral replication based on mammalian, avian, or insect cells. To overcome the inherent limitations in production outputs with serial propagation of cells, mammalian cells can be immortalized, which increases the number of times they can divide in culture. Modifications that immortalize cells are typically accomplished through mechanisms similar to those converting normal cells to…

Assay Acceptance Criteria for Multiwell-Plate–Based Biological Potency Assays

For most biopharmaceuticals, potency is assessed in a bioassay by comparing dose–response curves of the test material and a reference standard. As with all analytical techniques, such assays require criteria by which their execution can be judged objectively to be valid, regardless of whether the desired or expected result is obtained for the test sample. PRODUCT FOCUS: BIOLOGICSPROCESSFOCUS: R&D, QCWHO SHOULD READ: PRODUCT AND PROCESS DEVELOPMENT, ANALYTICAL, QCKEYWORDS: IMMUNOASSAYS, POTENCY ASSAYS, PRODUCT RELEASE, REFERENCE STANDARDS, CONTROL SAMPLES, SAMPLE ACCEPTANCELEVEL: ADVANCED…

Mathematical Model for Production of Recombinant Antibody 14D9 By Nicotiana tabacum Cell Suspension Batch Culture

Transgenic plants are increasingly considered a competing system for producing high-value recombinant proteins for biomedical and industrial purposes at affordable costs (1). Researchers have shown that molecular farming (or biopharming) is a secure technology that is capable of rendering valuable recombinant proteins free of toxins and animal pathogens in a relatively short time (2,3,4,5,6). Scientists have also demonstrated that most recombinant antibodies produced in plants maintain their functional properties (substantial bioequivalence) as well as do those produced in mammalian cell…

Quality Risk Assessment and Management Strategies for Biopharmaceutical Companies

You’ve probably been hearing a lot about risk assessment in recent months. Indeed, some 15 times more articles have been printed referencing the concept over the past year relative to a 12-month period just three years ago. That truly represents a geometric progression. Unfortunately, very few authors have been able to disambiguate the different methods or provide insight into this time-tested, multiple-industry philosophy that at its core uses good science to make better decisions. When we undertake the challenge to…

Robots in the Laboratory

Whether cell-based or molecular biology focused, most assays performed in biopharmaceutical laboratories involve liquid solutions. Increasingly, automated liquid handlers (laboratory robotics) are demonstrating utility in these labs, especially for high-throughput screening and optimization of cell culture media, chromatography conditions, formulations, and so on. Some experts say that screening 100,000 samples/day will soon become routine. But the robots haven’t condemned all manual pipettes to the trash heap — far from it. With multichannel and electronic pipettes improving throughput and reproducibility of…

Biological Assay Qualification Using Design of Experiments

In 2012, the United States Pharmacopeia (USP) published a complementary set of three guidance documents on the development, analysis, and validation of biological assays (1,2,3). USP chapter recommends a novel, systematic approach for bioassay validation using design of experiments (DoE) that incorporates robustness of critical parameters (2). Use of DoE to establish robustness has been reported (4,–5), but to our knowledge its use in qualification or validation protocols for assessing assay accuracy, precision, and linearity is not described in literature.…

High-Throughput Chromatography Screenings for Modulating Charge-Related Isoform Patterns

Monoclonal antibodies (MAbs) are an important class of biopharmaceuticals and are widely used to treat a variety of diseases such as cardiovascular diseases, cancer, and blood disorders. Antibodies are very complex proteins that show a high degree of microheterogeneities, including charge-, hydrophobicity- and size-related variances (1). Such variants can arise during any stage in a manufacturing process or storage as a result of enzymatic or nonenzymatic processes (2). Particular antibody variants that may affect the in vitro and in vivo…

Amplifying the Possibilities

Polymerases are natural enzymes that are vital to nucleic acid synthesis: DNA polymerase for replication of deoxyribonucleic acid and RNA polymerase for replication of ribonucleic acid. Thus all living things make and use polymerases of their own. But in 1969, the University of Wisconsin’s Thomas D. Brock and Hudson Freeze identified a new species of extremophilic bacterium thriving at 160 °F (70 °C) in a hot spring in Yellowstone National Park. In time, heat-tolerant polymerase isolated from Thermus aquaticus (Taq)…

Antibodies, Bioassays, and Cells

It’s no surprise that immunochemistry forms a broad and solid basis of biopharmaceutical analytical laboratory work. Immunochemicals include antibiotics and antigens, nucleic acids and nucleotides, enzymes, lipids, antioxidants, probes and dyes, and proteins and peptides. Available from companies such as Advanced Immunochemical, Immundiagnostik, Lampire Biological Laboratories, and Rockland Antibodies and Assays, their many uses include antibody isotyping and fragmentation. Adjuvants, buffers, assay kits, target biomolecules, and phage-display systems support those applications. Because background and off-target effects complicate the study of…

Rapid Detection of Pandemics

A Coronavirus — like severe acute respiratory syndrome (SARS) — is back in the headlines. On returning from a trip to Saudi Arabia in summer 2012, a Qatari national was struck down by a mystery respiratory illness. Because of inadequate diagnostic capabilities, the patient was transferred from Qatar to London for intensive-care treatment and diagnosis. The UK Health Protection Agency (HPA) confirmed infection with the same Coronavirus strain discovered by a Dutch team following the death of a Saudi national…