2.9 Tissue Cultures and Cell Lines
Cell lines obtained from commercial sources may become contaminated with adventitious agents while used in the laboratory. The extent of screening varies among providers and while most test for bacteria, mycoplasma, and fungi, they do not routinely include testing for viruses other than those categorized as ‘Bloodborne Pathogens’.
Cell cultures known to contain an infectious agent or oncogenic virus should be manipulated at the Biosafety Level appropriate for the agent, usually BSL-2.
For activities with materials not known to contain infectious agents, the following hazard classification applies:
BSL-1 is appropriate for well-established lines of cells of sub-primate origin if they do not harbor a primate virus and are free of bacteria, fungi, and mycoplasma. However, working with these materials at BSL-2 is recommended because of the additional degree of protection from contamination provided by BSL-2 practices, particularly the use of a Biological Safety Cabinet.
BSL-2 is appropriate for activities with: all primate cell lines, even well established ones, all cells derived from primate lymphoid or tumor tissues; all primate tissue; all human clinical material*; cultured cells new to the laboratory until proven contaminant-free; and, cells exposed to or transformed by a primate oncogenic virus.
*These activities and the use of any cells purposely infected with or suspected of harboring agents defined as bloodborne pathogens are covered by the Bloodborne Pathogens Standard). Laboratories using human cell strains (non‑transformed cells) propagated from primary explants must also comply with the Standard because they are considered “unfixed human tissue” which is covered by the regulation.