Standardization in animal cell technology.

Continuous cell lines offer a level of reproducibility, and thus standardization, which cannot normally be achieved using primary cells. However, even with continuous cell lines adoption of correct cell banking and appropriate quality control procedures are critical to the provision of reliable, reproducible and safe cell stocks. These procedures enable establishment of cryopreserved stocks of pure cultures of correct identity and phenotype which are free from adventitious agents. In addition to quality control techniques, culture conditions and growth medium used often require standardization. In particular different sources of serum, growth factors and cell attachment substrates may lead to significant variation in the 'performance' of cell lines. To ensure a high degree of reliability it is essential to obtain cells from authenticated and quality controlled sources. In culture collections, the principles of correct cell banking should be applied with appropriate quality control for which the minimum standard should be confirmation of viability and mycoplasma testing. Such approaches will afford increased confidence in research data and avoid the waste of time and resources which result from the use of cross-contaminated or infected cells.