click to enlarge The Thermo Scientific Cellomics Arrayscan VTI High Content reader helps researchers characterize stem-cell lines. (Image: Thermo Fisher Scientific).

Research on stem cells in the United States became easier when President Obama reversed the funding restrictions on embryonic stem cells. In fact, a range of stem-cell lines and products could increase traffic along many scientific avenues. “The market is quite large, and can be divided into two parts: the screening market and the therapy market,” says Mahendra Rao, PhD, vice president research, stem cells and regenerative medicine at Life Technologies, in Carlsbad, Calif. Rao sees the screening market as more immediately relevant, but adds that “with more than 100 clinical trials underway, the therapy market should move forward rapidly.”

Going Green click to enlarge Green fluorescent protein tracks differentiation in new stem-cell lines. (Image: Millipore)           When using stem cells in culture, researchers must keep track of the state of the cells. As Louise Rollins, product manager, stem cells at Millipore in Temecula, Calif., says, “Researchers need to continually characterize their cells to determine whether or not they have differentiated.” So Millipore developed the MilliTrace Line of GFP Reporter Stem Cells, which express green fluorescent protein (GFP) under the control of lineage-specific promoters, such as nestin and nanog. As Rollins explains, “The MilliTrace GFP Reporter cell lines allow you to quickly, and non-invasively, monitor the differentiation status of a stem-cell population. The loss of these stem-cell markers during differentiation causes down-regulation of the GFP, making it easy to determine which cells have differentiated.” These stem-cell lines offer a range of applications in drug discovery and development. As researchers look for compounds that impact stem cells, the Millipore lines could come in handy. As Rollins says, “The ability to conveniently monitor the behavior of specific stem-cell populations as they proliferate, migrate, and differentiate into various lineages will become increasingly important.”

Life Technologies offers a range of stem-cell lines and products as complete portfolios of matched reagents. It supplies neural stem-cell lines, rat primary cortical astrocyctes, rat glial precursor cells, as well as the associated media, enzymes, supplements, and cryopreservation reagents. The company recently released its KnockOut SR XenoFree, a media for human embryonic stem cells and human induced pluripotent stem (iPS) cells. “This lets researchers move from the bench to the clinic,” explains Rao.

Life Technologies also added stem cells to its custom services. With its discovery assay services, for example, customers can include stem cells. Rao says, “This service provides screening assays to pharma, and it has been extended so that assays can be performed in stem and differentiated cells.” For example, the company’s recent Jump-In TI Gateway Vector Kit can be used to integrate a desired gene into a stem-cell line. “This can target primary or stem cells in specific ways to do screening in a much more-controlled fashion,” says Rao.

Keeping track of stem cells and their pluripotency remains a challenge. So companies make products that characterize stem cells. For instance, Mark A. Collins, PhD, director of marketing at Thermo Fisher Scientific in Pittsburgh, Pa., says, “Utilizing high-content imaging, the Thermo Scientific Cellomics Arrayscan VTI High Content reader together with our range of Cellomics reagent kits can image—using fluorescent or transmitted light—individual stem cells, making a plethora of multi-parameter measurements to generate a cell-level ‘fingerprint’ to characterize that stem-cell population.”

Collins adds, “In general, the use of stem cells offers a much more relevant model for studying diseases than cultured cell lines and are much more convenient to handle than primary cells.” Consequently, stem-cell lines, coupled with high content screening make efficient engines for researching new drugs.

About the Author
Mike May is a publishing consultant for science and technology based in Houston, Texas.

This article was published in Drug Discovery & Development magazine: Vol. 12, No. 9, October, 2009, p. 8.