Cell lines are a crucial part of life science research and development. But did you know an estimated 18-36% of cell lines are believed to be misidentified or cross-contaminated with another cell line?
Misidentified cell lines are becoming so problematic in journals and clinical trials that authentication is commonly being required before publication, while grant funding agencies are highly recommending it. NIH grant applications are now including a section for applicants to describe their authentication plan. To read more about these requirements visit this announcement from the NIH or go here for a complete list of journals with guidelines.
What is STR Profiling?
Luckily, there is a simple solution out there! Cell line authentication by STR profiling is able to provide quick and reliable data to confirm that the cell line you are currently growing is indeed what you think it is. STRs, or short tandem repeats, are short DNA sequences that can be used to create a genetic profile. By comparing the STR profile from the sample in question to the cell line’s reference data, you can determine if your cell line is truly a genetic match. STR profile reference data is available through databases found on the websites of major cell repositories.
There are many different options for implementing STR analysis in your lab. First, find a reputable company that offers the service and then collect a small sample of your cells. Most labs will accept frozen, fresh, or dried cell pellets or genomic DNA samples. There are even much simpler options, such as spotting cells onto a mail-order form which will be sent back to the laboratory for analysis. Finally, you can choose to have the company analyze the data for you or you can interpret it yourself. All of these options have different prices, so do some research and decide what will work best for initiating this process in your lab.
Be aware that STR profiling is only available for human cell lines, but some testing facilities do include a mouse marker. While it will not tell you what the mouse cell line is, it can at least determine if a mouse cell line is present where it shouldn’t be.
This technology is extremely important because simply passaging cell lines continuously can lead to genetic drift and environmental adaptations, so much so that the cells are no longer what they once were. These are the important stages when you should check the identity of your cell lines:
- At an early passage to establish cell line identity
- Before beginning a new study and again right before publication
- Before freezing down a new working bank
- When the cell line is not behaving as expected
To support our commitment to reproducibility, cell line authentication was implemented many years ago. Customers can be reassured that our validation efforts are taking place right down to the cellular level.
Cell line authentication can save you from discovering that hours, months, or even years of your hard work and research are compromised due to misidentification or cross-contamination of a cell line. Take measures now to prevent your laboratory from realizing that your research cannot be reproduced or progressed. If you’re still not convinced it’s a serious issue, consider all the various HeLa cells being grown in labs around the world that should be the same...but aren't!
And as always, remember that no single assay is enough to validate an antibody!