Biopharmaceutical manufacturing will continue to be increasingly challenging as medical knowledge and understanding rapidly advance. Many new therapies and products will utilize cellular, viral, genetic, and epigenetic approaches along with a repertoire of increasingly complex proteins targeting a rapidly increasing inventory of newly discovered biomarkers. Manufacturing these products efficiently, consistently, and reliably will require sophisticated manufacturing approaches, methods, and controls. In addition, growing patient, societal, and even regulatory pressures demand that new therapeutics be developed and manufactured quickly, reliably, and efficiently. Historically, manufacturing has been viewed and managed in terms of minimizing patient safety risks.
Category: <span>Regulatory</span>
Plaque assays have traditionally been a reliable way to determine the titer of a lytic virus. However, this method has several shortcomings in that it is time-consuming, labor intensive, and suffers from limited sensitivity. In this article, we describe a novel flow cytometry-based titration assay to quantify green fluorescent protein-labeled herpes simplex virus type 1 (HSV-1-GFP). Using this assay, we were able to directly quantify ten-fold dilutions of the virus in which every GFP-positive cell could be counted. In a head-to-head comparison with a traditional plaque assay, the flow cytometry assay showed a greater linear range and was accomplished in less than half the time of the plaque assay.
Antibody-dependent cellular phagocytosis (ADCP), which relies on macrophages to attack and devour tumor cells following antibody binding, is a potentially useful mechanism of action (MOA) for antibody drug developers and vaccine makers to consider in determining product efficacy. Unfortunately, it is often ignored in favor of more accessible MOAs driving biological function such as antibody-dependent cellular cytotoxicity (ADCC) because the assays are tedious to prepare, perform, and reproduce.