Question

Asked 10 October 2018

German Cancer Research Center

STR analysis for cell line authentication - Anyone experienced with ?

Hi Everyone,

can anyone tell me if there is any issue with reliability for STR analysis when authenticating a cell line?

Otto-von-Guericke University Magdeburg

Kais Khudhair al Hadrawi

Al-Furat Al-Awsat Technical University

Annemarie Honegger

University of Zurich

Karen A. Darbinyan

Seied Mehdi Miri

Islamic Azad University, Karaj

Amos Bairoch

University of Geneva

It all depend on what you mean by "reliability": good STR profiling services will send you not only the allele assignments for all the markers that they have tested (currently most companies/services will report on 18 markers) but they will also send you the chromatograms which can help you pinpoint potential minor alleles. So all this is quite "reliable": but then the interpretation of these results may be, in some cases, ambiguous: many cell lines STR profiles were reported with 8+1 (amelogenin) markers and "your" cell line could well have many hits with one of these cell lines without being identical or derived from it. In addition some cancer cell lines can drift quite quickly and loose alleles compared to the "original" stock.

But if your are comparing a cell line you are using with what should be the "original" one you will generally have no issue determining if it is the right one. Similarly contamination with known frequent contaminants (HeLa, HT-29, K-562, T24) are rather easy to diagnose.

Just make sure to make use of a well established cell line authentication service, which is not a problem in Germany, home of the DSMZ and CLS cell line collections which both offer such services.

Best

Amos

PS: While there is not yet a tool to search and compare STR profiles, you can use the Cellosaurus (https://web.expasy.org/cellosaurus/) to look up STR profiles for more than 5,500 human cell lines

Cite

Thales De Paula Ribeiro

German Cancer Research Center

Thank you very much for your detailed answer Dr. Bairoch. It was really helpful.

Cite

Amos Bairoch

University of Geneva

To complete my answer from last year, there is now a STR similarity search tool for the Cellosaurus. It is available at:

https://web.expasy.org/cellosaurus-str-search/

Cite

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