: Can you tell us what your company is doing to address the cell line authentication problem?
MdM: Since 1986, ATCC has been the leader in identifying and authenticating human cell lines via short tandem repeat (STR) profiling. ATCC routinely performs STR analyses on its human cell lines, and has created a searchable online database of STR profiles from the resulting data. The ATCC STR Profile Database provides researchers in industry and academia with an easy-to-use comparative tool to cross-reference STR profile queries against hundreds of human cell lines maintained by ATCC. Further, this large data set is employed as a reference against the profiles generated by the ATCC Cell Authentication Service, enabling a comprehensive interpretation of the assay results.
Additionally, ATCC was instrumental in developing the current standards for STR in human cells. Through the American National Standards Institute (ANSI)–accredited Standards Development Organization (SDO) at ATCC, a consensus standard was developed and published: ANSI/ATCC ASN-0002-2001 Authentication of Human Cell Lines: Standardization of STR Profiling. We are also working with the National Institute of Standards and Technology (NIST) under two collaborative research and development agreements (CRADAs) to develop the STR technology for mouse cell lines as mouse is the next most represented species in cell lines after human. Once the technology and protocols are defined, we would like to pursue the development of a consensus standard for the authentication of mouse cell lines.
: Do you provide services or materials (such as published white papers, technical guides, or other references) to researchers to ensure that cell lines are authenticated?
MdM: There are a number of ways ATCC supports researchers in their cell line authentication efforts. As I mentioned previously, we routinely perform STR profiling as a component of our stringent quality control analyses. Further, we provide an STR profiling service that allows researchers to send in their samples to be tested against an extensive database, with the results analyzed by experts. I would also like to emphasize that cell authentication should embrace not only identity, but purity. To support this, ATCC offers both a mycoplasma detection kit for laboratory use and a service for mycoplasma detection that enables researchers to determine if their cultures are contaminated with this common, yet hard-to-control organism. Additionally, for animal cell lines, we have published a consensus standard on the use of the CO1 subunitof the cytochrome oxidase subunit 1 (CO1) gene to provide reliable species-level identification. The portfolio of resources on our website include several technical and application notes to help guide customers in the use, application, and understanding of cell authentication methods and benefits.
: Do you provide any training?
MdM: The training we provide is available in different formats. On our website, we have several videos highlighting and illustrating STR profiling and mycoplasma detection. We also provide a tutorial for customers that are performing their own STR analyses and using our database to compare STR profiles. Further, we host wet-lab training in cell culture techniques to support one of our ongoing federal grants.
: Knowing what we know now about contaminated and misidentified cell lines, why do you think researchers persist in using cell lines that haven't been authenticated?
MdM: This was a topic that was brought up during an NIH sponsored workshop to promote reproducibility in research, and also the focus of a survey sponsored by the Global Biological Standards Institute (GBSI). It was found that over half of researchers do not authenticate their cell lines. There are 3 main reasons for this: 1) the cost of authenticating one cell line at one time can be done for $100–$150, this can add up for multiple cell lines and multiple times (these costs have not been historically covered in research grants); 2) the time it takes to make authentication a routine part of the research; and 3) delays in research if issues are uncovered. Interestingly, at the NIH workshop there were admissions that the consequences of uncovering issues with cell lines, particularly in well-established labs with an ongoing cell model, were too daunting. Additionally, a lack of awareness and complacency are significant factors.
: Are there certain resources you suggest your customers use on a routine basis to get help or information?
MdM: There are a number of resources that provide guidance in understanding the need for cell authentication as well as the associated techniques and results. On our website, we provide a comprehensive list of references as well as the several videos I previously mentioned. Another resource is the Registry of Misidentified Cell Lines, which is compiled and updated by the International Cell Line Authentication Committee (ICLAC). This growing registry contains over 485 cell lines and is an important resource for investigators in the early phases of their research. Another invaluable resource is a series of publications on best practices in cell culture, which was produced last year by the Society of In Vitro Biology in the journal In Vitro Cellular & Developmental Biology - Animal. This effort was led by Dr. Yvonne Reid, a world renowned cell culture expert who recently retired from ATCC after 35 years of service, and included content from a group of leading cell culture subject matter experts.
I did want to mention a notable milestone in the recognition of the need for routine cell authentication. In 2015, the NIH released the notice “Enhancing Reproducibility through Rigor and Transparency” to inform scientists of the revised application instructions for funding grants submitted on January 25, 2016, and beyond. The notice specifically states, “NIH expects that key biological and/or chemical resources will be regularly authenticated to ensure their identity and validity for use in the proposed studies. . . . These include, but are not limited to, cell lines, specialty chemicals, antibodies and other biologics.” Concurrently, a rapidly growing list of journals (including the major ones) now have recommendations/requirements for cell authentication, so it is important to be aware of which journals have set guidelines for cell line authentication prior to publication. It is best to refer to the publication guidelines set forth by each journal.
: ATCC has been very involved in developing standards. Why are standards important and how do you ensure that researchers are aware of new standards?
MdM: At the highest level, standards are the key to reproducibility in research and development. As a provider of many of the fundamental tools of research and development, it is essential for ATCC to ensure that our products are of the highest quality through extensive authentication, testing, and traceability. It is also our mission to help guide the development and availability of standards to the larger scientific community so that the methods can be broadly applied, and the results are consistent and reproducible. The best way to do this is through engaging and working with experts in the scientific community to develop universally available consensus standards through our ANSI-accredited SDO. New standard development and publication has been and will be communicated through ATCC channels (website, notes, and presentations) and publications in peer reviewed journals.
: Does ATCC offer STR profiling services? If so, what does the service include, and how often should it be done?
MdM: ATCC currently offers an STR profiling service for human cell lines. Here, the customer receives a sample collection card upon their purchase of the service. After the sample is spotted onto the collection card and subsequently dried, it can be mailed back to ATCC in the provided envelope. Once at ATCC, the sample is tested under an ISO 17025:2016 certified process for STR authentication that uses barcoded sample and process controls. The resulting STR profile is compared against the expansive ATCC STR Profile Database to provide a detailed report containing the probable identity with the probability included. Results are emailed to the customer within 3-5 business days along with an STR report that meets requirements for funding, publication, and quality control. We would like to bring on mouse STR as well once the Mouse Consortium Project with NIST is complete. As to how often STR profiling should be performed, it is recommended that cells are authenticated when you start a project (or better yet, use a fresh vial) as well as routinely during the project.
: Does ATCC offer any other testing services?
MdM: Currently, ATCC offers STR profiling for human cell lines, CO1 testing for interspecies determination, and mycoplasma detection. However, stay tuned for the expansion our authentication services portfolio as other technologies, such STR profiling for mouse cell lines, are developed.
ATCC is dedicated to strengthening biological research and bolstering experimental data by advocating best practices in cell culture. By routinely authenticating your cell lines as well as other critical research components, the individual researchers and the scientific community are better served as the results will be more reliable and reproducible.
Author bio: Maryellen is Vice President of ATCC’s Standards Resource Center (SRC), a business unit focused on standards and related services. The SRC includes the Central Acquisition Unit (CAU), the Standards Development Organization (SDO), Services and Metrology R&D.
Prior to joining ATCC, Maryellen was Chief Operating Officer and Vice President of Clinical Operations at USDS, Inc., an independent third party evaluating the performance of molecular diagnostic tests to support regulatory, reimbursement, and adoption efforts. She also served as Director of Clinical Biomarkers at Critical Path Institute (C-Path), leading collaborative efforts to evaluate and improve the use of clinical biomarkers and optimize the pathway for development of companion diagnostics. She served as Executive Director of Genomics Services and Director of Biorepository at Gene Logic, Inc., and led business development and marketing efforts at Life Technologies, Inc.
She earned her Ph.D. in Virology from the University of Texas, and completed postdoctoral training in transcriptional regulation at The Johns Hopkins University.