The seed stock concept and quality control for cell lines.

Procedures for the characterization of cell culture lines are reviewed. It is recommended that seed stocks be developed and that major quality-control efforts be applied first to those holdings, with essential tests repeated on cultures from working or distribution stocks prepared subsequently. Steps are taken throughout to ensure absence of microbial contaminants. Mycoplasma are especially troublesome. Investigators need also to be aware of potential endogenous viruses which may be hazardous or interfere with interpretation of results. Cell line species and absolute identities are established by fluorescent antibody staining, by determination of isoenzyme profiles, and by cytogenetic analyses. Additional characterizations will vary with cell type but may include tests for specific products, cytoskeletal proteins, tissue specific antigens, or immunoglobulins. Credentials of lines added to a collection plus representative cultures can be returned to the originators for concurrence before distribution. Advisory committees may be established as circumstance dictates to provide additional expertise regarding quality control for the specific collection being developed.