Cell-based bioassays are routinely used for the assessment of product potency, comparability and stability testing, pharmacokinetic and pharmacodynamic properties, or determine the ability of anti-drug antibodies to neutralize the biological effect of the drug in a cell based system. In addition, cell cultures can also be the source of key biological reagents such as monoclonal antibodies or enzymes that are used in ligand binding or enzymatic assays. In all of its applications, the cell itself serves as a highly critical, highly complex “reagent” in the analytical test assay that requires distinct characterization and control measures to ensure operational consistency with each use. These assays must provide accurate information throughout the product development and on the market. The accuracy and reliability of cell based bioassay test results depends on controlled, consistent banks of designated cells.
There are evolving industry practices on preparing, characterizing and storing cell banks used specifically for bioanalytical test assays. Timelines for the generation of cell banks, growth conditions, purity, reproducibility, equipment and stability, should be considered. Establishment and maintenance of assay cell banks is a major element of test assay qualification and validation to assure that assays using cell cultures will be reliable and robust from pre-clinical stage to marketing.
Appropriately established and stored master and working cell banks (MCB/WCB) can better assure the continued supply of viable cells that can be used to generate accurate, reliable results.