Tissue Culture: Mammalian Cell Cultures
Workers who handle or manipulate human, non-human primate, or other mammalian cell lines and tissues are at risk for possible exposure to potentially infectious latent and adventitious agents that may be present in those cells and tissues. The potential for human cell lines to harbor a bloodborne pathogen led OSHA to include human cell lines in the final rule unless they were specifically tested for, and documented to be free of, human bloodborne pathogens.
There also is evidence of accidental transplantation of human tumor cells to healthy recipients, indicating that these cells are potentially hazardous to the laboratory workers who handle them. Further, human and animal cell lines that are not well characterized or are obtained from secondary sources may introduce a biohazard to the laboratory.
Note that cell lines purchased from companies like ATCC are not routinely tested for viruses, including those that may be human or animal pathogens.
However, ATCC has recently announced that it will test every lot of every human cell line manufactured after January 4th, 2010 for common human viral pathogens: HIV, HepB, HepC, HPV, EBV and CMV.
Biosafety Level 2 is appropriate when work is done with any mammalian cell line that has not been well characterized or where the presence of an infectious agent may be unknown.