Check your cultures! A list of cross‐contaminated or misidentified cell lines

Abstract

Continuous cell lines consist of cultured cells derived from a specific donor and tissue of origin that have acquired the ability to proliferate indefinitely. These cell lines are well‐recognized models for the study of health and disease, particularly for cancer. However, there are cautions to be aware of when using continuous cell lines, including the possibility of contamination, in which a foreign cell line or microorganism is introduced without the handler's knowledge. Cross‐contamination, in which the contaminant is another cell line, was first recognized in the 1950s but, disturbingly, remains a serious issue today. Many cell lines become cross‐contaminated early, so that subsequent experimental work has been performed only on the contaminant, masquerading under a different name. What can be done in response—how can a researcher know if their own cell lines are cross‐contaminated? Two practical responses are suggested here. First, it is important to check the literature, looking for previous work on cross‐contamination. Some reports may be difficult to find and to make these more accessible, we have compiled a list of known cross‐contaminated cell lines. The list currently contains 360 cell lines, drawn from 68 references. Most contaminants arise within the same species, with HeLa still the most frequently encountered (29%, 106/360) among human cell lines, but interspecies contaminants account for a small but substantial minority of cases (9%, 33/360). Second, even if there are no previous publications on cross‐contamination for that cell line, it is essential to check the sample itself by performing authentication testing.

BCR – ABL1 expression in multiple myeloma cells: A case of mistaken identity?

“…Standardized PCR-based methods are now available for authenticating cell lines by reference to an interactive cell line database (www.dsmz.de/services/services-human-and-animalcell-lines/online-str-analysis.html), although continually updated lists of false examples are published (5). It is now up to journals and grant agencies to encourage full exploitation of these resources.…”

Establishment of the cell line, HeLa-CD14, transfected with the human CD14 gene

“…This cell line has revealed much efficiency and stability in extrinsic gene transfection (13)(14)(15); in this study, we selected the cell line as the host cell and conducted the human CD14 gene transfection into it.…”

Species identification and authentification of human and rodent cell cultures using polymerase chain reaction analysis of vomeronasal receptor genes

“…Several studies over the past decade have demonstrated the problem of cell line contamination which generally arises due to poor laboratory practice (Capes-Davis et al 2010). Reported reasons include cell spreading via aerosols, use of unplugged pipettes, sharing media/reagents between cell lines and the use of mitotically inactivated feeder cells or conditioned medium, which have not had originating cells removed (van Pelt et al 2003).…”

“…These continuous cell lines are repeatedly passaged, reliably cryopreserved and retain representative properties of the cells and tissues from which they were derived. These attributes have resulted in cell lines being widely used as model systems for the study of cellular processes in health and disease and are therefore commonly used within biomedical research and the pharmaceutical industry (Capes-Davis et al 2010). Recently the robustness of cell cultures used in research has been under scrutiny as data have demonstrated that cross-contamination with other cells lines, misidentification of cell lines, and the use of cultures at high passage numbers has resulted in the generation of erroneous results (Hughes et al 2007).…”