Approximately 7000 studies involved contaminated HEp-2 and INT 407 cell lines.
A recent analysis found that thousands of scientific studies could be incorrect due to cell lines were contaminated or misidentified.
Although this issue has been known about for 35 years, journals have not yet issued disclaimers for these potentially effected studies, STAT reported. The HeLa cell line, a cervical cancer cell line, is known to proliferate and contaminate any cells it comes in contact with.
The HEp-2 and INT 407 cell lines are now known to be contaminated with HeLa cells. It was estimated that more than 7000 studies used the contaminated cell lines, thinking they were HEp-2 and INT 407, according to the study. This contamination can happen from something as simple as transferring 1 cell line from a glove or a piece of equipment to another cell line.
If it happens at the beginning of cell growth, 1 single cell could take over the culture without any signs that a change has occurred. Aware of this occurrence, the journal Nature and its other publications require study authors to verify (without proof) that they have checked their cell lines’ identity, according to the article.
However, no journals have created disclaimers for studies known to have used contaminated cells. They also have not retracted these studies either.
This contamination has the potential to affect future research and could impact experimental treatments, the article concluded.