Australasian Science: Australia's authority on science since 1938

Medical Research Must Come Clean

By Mark Shannon

Up to one-third of cell lines may be contaminated, threatening the reliability of research.

Medical research often uses cell lines – cells taken from a human or animal and grown in a laboratory – to evaluate potential therapies. Cultured cells need everything that they’d normally get in nature, but supplied artificially. One wrong step could cause the cells to die.

Another misstep could introduce contaminants to the culture. Microbial contamination, especially by Mycoplasma species, can have major impacts on cell culture results even if there aren’t any visible sign of contamination. Cross-contamination between cell lines may also make experimental results unreliable.

Concern about research reproducibility has grown over the past few years. It’s impossible to know the true extent of the cell line contamination problem today, but up to one-third of cell lines could be affected worldwide.

A few years ago I joined CellBank Australia, our only not-for-profit national cell line repository. I soon learned that while many labs were using CellBank Australia’s validated cell lines and related services, other labs were not aware of the risks of cell line contamination. I wanted to know how we could help, so we asked the scientists themselves and more than 250 responded.

Our survey, published in The International Journal of Cancer ( found that sharing of cell lines between laboratories is widespread in Australia and New Zealand and that Mycoplasma and authentication testing arrangements are increasingly in place. However, scientists often don’t know how to test cells to be sure that they are authentic and not some other cell line.

So what can be done to reduce cell culture contamination and make medical research in Australasia more reproducible?

Common cell culture risks can be more effectively addressed by training scientists to attain minimal standards for cell culture practice. Researchers can obtain cell lines from sources that perform Mycoplasma and cell authentication testing, or they can arrange for that testing to be done as soon as the cells arrive in their labs – prior to the commencement of new projects.

Published cell lines can also be placed in cell line repositories, where their quality can be assured before the cells are widely distributed. Repositories can make it easier for scientists to access quality-validated cell lines.

Research journals can introduce reporting measures so that readers of published studies know about the quality of cell lines used. Research funding agencies can likewise introduce funding application instructions and review criteria that focus on cell line quality assurance for research reproducibility.

I know that the risk of contamination will remain despite the best cell culture practices, but this can be managed to a much lower level: the Australasian research community is in great shape to do this. Good cell culture practice is not a new concept to many of us, and in CellBank Australia we already have our own national cell line repository.

The wave of concern around research reproducibility is now so strong that it would be risky to ignore the part played by cell line contamination. Each of us now needs to make a choice. Do we quickly get to the crest of the wave by our own volition, where we can enjoy the ride? Or do we stand still and wait for the wave to crash down on us, only to be pulled along in the undertow afterwards?

I think there’s only one real choice.

Mark Shannon is General Manager of CellBank Australia.