Received on March 23, 2005
Accepted on August 10, 2005

Molecular Diagnostics and Genetics

Genetically Characterized Positive Control Cell Lines Derived from Residual Clinical Blood Samples

¹ Department of Pathology, Duke University Medical Center, Durham, NC
² Coriell Cell Repositories, Coriell Institute for Medical Research, Camden, NJ
³ National Center for Health Marketing, Division of Public Health Partnerships, Centers for Disease Control and Prevention, Atlanta, GA
⁴ Specialty Laboratories Inc., Molecular Genetics Laboratory, Santa Monica CA
⁵ Mayo Clinic, Molecular Genetics Laboratory, Rochester, MN
⁶ The Methodist Hospital, Houston, TX
⁷ Greenwood Genetic Center, Greenwood, SC
⁸ Nichols Institute, Quest Diagnostics, San Juan Capistrano, CA
⁹ Department of Medical Genetics and Department of Pathology, University of Tennessee Medical Center, Knoxville, TN

^* To whom correspondence should be addressed. E-mail: timothy.stenzel{at}abbott.com.

Background: Positive control materials for clinical diagnostic molecular genetic testing are in critically short supply. High-quality DNA that closely resembles DNA isolated from patient specimens can be obtained from Epstein-Barr virus (EBV)-transformed peripheral blood lymphocyte cell lines. Here we report the development of a process to (a) recover residual blood samples with clinically important mutations detected during routine medical care; (b) select samples likely to provide viable lymphocytes for EBV transformation; (c) establish stable cell lines and confirm the reported mutation(s); and (d) validate the cell lines for use as positive controls in clinical molecular genetic testing applications.

Methods: A network of 32 genetic testing laboratories was established to obtain anonymous, residual clinical samples for transformation and to validate resulting cell lines for use as positive controls. Three panel meetings with experts in molecular genetic testing were held to evaluate results and formulate a process that could function in the context of current common practices in molecular diagnostic testing.

Results: Thirteen laboratories submitted a total of 113 residual clinical blood samples with mutations for 14 genetic disorders. Forty-one EBV-transformed cell lines were established. Thirty-five individual point and deletion mutations were shown to be stable after 20 population doublings in culture. Thirty-three cell lines were characterized for specific mutations and validated for use as positive controls in clinical diagnostic applications.

Conclusions: A process for producing and validating positive control cell lines from residual clinical blood samples has been developed. Sustainable implementation of the process could help alleviate the current shortage of positive control materials.