All Eyes on Stem Cells
StemCell Technologies (www.stemcell.com) has followed the evolution of stem cell research, early on bringing to the market standardized media and reagents designed for cultivating hematopoietic stem cells and associated assays for characterizing and enumerating stem and progenitor cell populations. The company’s emphasis continues to focus on developing standardized conditions for stem cell culture based on optimized media and reagents that yield consistent, reproducible results both within and across laboratories.
Now, as the variety of stem cells being used for research and potential clinical applications has grown to include nonhematopoietic stem cells, including mesenchymal and neural stem cells, Sharon Louis, Ph.D., senior scientist at StemCell Technologies, once again sees the need for standardization of basic research tools and culture conditions, so researchers can compare data produced in different labs. This includes the need for standardized media optimized for these new stem cell populations and for standardized assays to identify and quantify stem cells and facilitate their isolation without contamination by other cell types.
“We have moved into the mesenchymal and neural stem cell field, as well as offering products designed for use with endothelial and breast stem cells and human and mouse embryonic stem cells,” explains Dr. Louis. She notes a growing demand for ESC research products.
According to Dr. Louis, even though the existence of neural stem cells was reported nearly 15 years ago, there is still not one standardized medium and set of protocols for growing neural stem cell colonies and measuring neural stem and progenitor cells. Various labs continue to use different combinations of cytokines and growth factors. “Standardization of the tools will bring the needed robustness and stringency to the early stages of stem cell research,” she adds.
PAA (www.paa.com) offers a range of media and reagents for the growth and differentiation of stem cells, including hematopoietic, mesenchymal, neuronal, and embryonic stem cells.
“It is important for labs to agree on the same platform for cell cultivation,” points out Susan Donath, product manager at Miltenyi Biotec (www.miltenyibiotec.com), emphasizing the need for standardized solutions. She describes a similar requirement for defined cytokine and growth factor preparations for use in cell culture and differentiation.
Different labs may generate contradictory results regarding the differentiation potential of a stem cell line, for example, but it might be unclear whether those differing results are due to the cell line itself or the culture conditions. The growing importance of being able to compare results between laboratories is contributing to the need for chemically defined media in stem cell research.
“The big trend at the moment is the move away from undefined media formulations,” says Erik Schneider, head of clinical product development. There has been a gap between efforts to enrich for cells with potential therapeutic applications and their subsequent use in a clinical environment, Schneider adds.
This regulatory gap is driving the push for sera- and animal component-free, defined media. Some alternative formulations to replace sera, such as soybean hydrolysates, which are plant-based and fulfill the need for an animal-free product, are under development.
Miltenyi Biotec is building on its cell separation systems designed for isolating defined cell populations and is offering culture media optimized for the cultivation and differentiation of enriched stem cell populations. Examples include the company’s MACS® stem cell media for cultivating hematopoietic and nonhematopoietic stem cell populations, including mesenchymal stem cells, and media designed for the expansion and isolation of antigen-specific T-cell populations. Media for the expansion of different populations of immune cells are also in development.