Upstream Processing

Reference Standards for Therapeutic Proteins: Current Regulatory and Scientific Best Practices

Sponsors developing and manufacturing protein therapeutic products use a variety of analytical tests (e.g., cell-based potency and chromatographic assays) to assess quality attributes of their active ingredients and drug products. Those tests are used to assess product quality in a number of activities, including characterization, comparability, lot release, and confirmation product quality and stability. Reference standards play a critical role in calibrating and confirming the suitability of such tests and in helping analysts to draw scientifically sound conclusions from data…

Cell Therapy Bioprocessing Technologies and Indicators of Technological Convergence

The cell therapy industry is undergoing a natural evolution from scientific curiosity into a commercially and clinically attractive opportunity (1). This evolution is by no means complete, and growing evidence suggests that its progression is driving significant developments in cell therapy bioprocessing — notably, convergence. Table 1:&#8 194; () Progressively, bioprocessing technologies primarily used in production of noncell-based products are being evaluated for cell therapy bioprocessing applications (2). Consequently, this process of convergence is leading to an increasing proportion of…

Single-Use, Continuous Processing of Primary Stem Cells

Many potentially therapeutic products involve the culture of stem cells. Their commercial success depends on the development of scalable good manufacturing practice (GMP) technologies that can both robustly and cost-effectively produce very large numbers of cells. Through many improvements and innovations in bioprocessing operations over the years, fed-batch suspension culture has remained the most common mode for large-scale biopharmaceutical manufacturing. However, some recent events suggest that may be changing (1,2). For the culture and expansion of stem cells, large-format adherent…

Single-Use Bioreactors and Microcarriers

Cell-based therapies hold promise for treating many acute and chronic diseases (1). Optimism surrounding that therapeutic potential has driven the initiation of multiple clinical trials in pursuit of such treatments. Procedures for preparing these therapeutic agents begin with selective isolation of cells from desired tissues. That is followed by ex vivo expansion of cells of desired phenotype and functionality. Once expanded to acceptable levels, cells are stored to preserve their viability during transportation to treatment facilities. The final step in…

Activatable Immunoconjugates for Target Cancer-Cell–Specific Diagnosis and Therapy

In cancer treatment, early diagnosis and targeted therapies are assumed to yield the highest cure rates. However, most current methods are limited by their low sensitivity to early disease and a lack of specificity for targeted cell killing. Newly developed, activatable immunoconjugates assist in the accurate detection of cancer through in vivo imaging with high target-to-background contrast (1,2). They also provide for the possibility of highly specific, light-mediated treatment with minimal effects on healthy cells surrounding tumors (3). In fact,…

Powders and Bulk Liquids

    The two major bioprocess fluids — culture media for upstream production and buffers for downstream processing — are classic single-use products. They are used once and then disposed of. The two basic options for both differ by physical state: powdered media and buffers (“powders” for in-house preparation of liquids by end users) and bulk liquid culture media and buffers, which are fully prepared by their suppliers (“liquids”). We conducted market research studies comparing the benefits and risks (value…

Effective Cryopreservation and Recovery of Human Regulatory T Cells

The list of conditions being targeted by cell therapies is rapidly growing, but commercializing cells for widespread medical use will require standardized laboratory practices. Development processes must be adapted specifically for cell-based drug products. Regulatory T-cell therapy represents a promising new frontier in the immunotherapy of autoimmune disorders, especially for patients who have been refractory to available treatments. Because of intrinsic fragility, cell therapy products can be highly sensitive to variations in manufacturing procedures. Standardization of drug-product cryopreservation and storage…

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…

IgM Purification with Hydroxyapatite

Hydroxyapatite (HA) has a long and successful history in the field of antibody purification, and it has worked well for immunoglobulin M (IgM) monoclonal antibodies (MAbs) (1,2,3,4,5,6,7,8). Applications range from initial capture to intermediate purification to final polishing. HA is best known for its superior ability to reduce antibody aggregates, but it also supports excellent reduction of DNA, viruses, and endotoxins. As IgM MAbs exhibit increasing potential in the fields of cancer and infectious disease and in stem-cell therapies, HA’s…

North, South, East, and West

Electrophoresis is the basis of all blotting methods, and BPI Lab covered it last month (1). Electroblotting is a method for transferring electrophoretically separated proteins or nucleic acids onto a polyvinylidene fluoride (PVDF) or nitrocellulose membrane for permanence using electric current and a transfer buffer solution. This allows for analysts to further study them using probes, ligands, or stains. Capillary blotting is a variation designed to work with capillary electrophoresis. After electrophoresis the following are stacked in cathode-to-anode order: a…