An international team of scientists led by researchers at The Scripps Research Institute has developed a straightforward technique to determine the ethnic origin of stem cells.
The Scripps Research scientists initiated the study-published in the January 2010 edition of the prestigious journal Nature Methods-because the availability of genetically diverse cell lines for cell replacement therapy and drug development could have important medical consequences.
Research has shown that discordance between the ethnic origin of organ donors and recipients can influence medical outcomes for tissue transplantation, and that the safety and effectiveness of specific drugs can vary widely depending on ethnic background.
The team’s analysis of a variety of human embryonic stem cell lines currently in use in research laboratories around the world found that these cells originated largely from Caucasian and East Asian populations, with little representation from populations originating in Africa.
In response to these results, the scientists used skin cells from an individual of West African Yoruba heritage to create a new stem cell line, the first to carry the genetic profile of this ethnic group.
“Ethnic origin is a critical piece of information that should come with every cell line,” said Scripps Research Professor Jeanne Loring, Ph.D., who is senior author of the paper. “Everyone who works with stem cells should be doing this kind of analysis."
“Knowing that a big push in the future is using these lines in the clinic and in drug development, there’s a need to have an ethnically diverse population of cells,” added Louise Laurent, M.D., Ph.D., assistant professor at the University of California, San Diego (UCSD) and research associate at Scripps Research, who is first author of the paper with Caroline Nievergelt, Ph.D., also an assistant professor at UCSD.
Greater diversity in cell samples would set the stage for broadly relevant research by labs in academia and industry, more robust results on the safety and efficacy of potential therapies, and more successful tissue transplants.
Normally, cells develop from stem cells into a myriad of increasingly more specialized cell types during early development and throughout a lifetime. In humans and other mammals, these developmental events are usually irreversible. This means that when tissues are damaged or cells are lost, the body has limited means by which to replenish them.
Having a source of stem cells would be useful in many medical situations because these cells are "pluripotent," having the ability to become any of the body's cell types. Pluripotent stem cells would potentially provide physicians with the ability to replace or repair damaged tissues throughout the body. For example, pluripotent stem cells could be differentiated into the damaged cell type and transplanted.
Much research on pluripotent stem cells to date has been conducted on human embryonic stem cells, which are harvested from discarded embryos (those created but not used for the purposes of in vitro fertilization, a technique to help couples conceive). However, recently another source of pluripotent stem cells has come onto the scene. These cells—called induced pluripotent stem cells—are created by taking a sample of skin cells or another type of differentiated cell and using chemicals and molecular biology techniques to coax them back into a pluripotent state.