By Tom Still
MADISON – The world now knows about Hwang Woo-suk, the South Korean researcher whose stem cell work may have been falsified. It was a confidence-shaking revelation for some who support human embryonic stem cell research, and a gleeful “I-told-you-so” opportunity for those who do not.
If there’s a positive side to the alleged research abuses in South Korea, it is the contrast with how stem cell science is conducted elsewhere. Hwang’s transgressions support what bona fide researchers in the United States have been saying all along: “We operate under clear, ethical rules that may take longer to produce research results, but you can count on those results once they’re announced.”
The latest breakthrough by Dr. James Thomson and other scientists at the WiCell Research Institute, a private laboratory affiliated with UW-Madison, illustrates the point.
Thomson and others have developed a precisely defined stem cell culture system free of animal cells and used it to derive two new human embryonic stem cell lines, named WA 15 and WA 16, from donated frozen embryos. Stem cells are the building blocks of human life; all organs and tissues “stem” from these basic cells. With research under way around the world, scientists believe stem cells will eventually yield knowledge about cures for diseases, treatments for chronic conditions and drug therapies.
The UW discovery, reported early this month in the journal Nature Biotechnology, is scientifically important because it shows stem cell lines can be grown successfully without animal contamination. By completely ridding the culture medium (a blend of nutrients, hormones, growth factors and blood serum) of animal cells, stem cell research has moved a step closer to clinical reality. Scientists were concerned that human stem cells grown in cultures that included animal cells might become contaminated with animal viruses or other agents. Now, it is possible to develop lines that could be used for therapy without fear of animal taint.
“All of the concerns about contaminating proteins in existing stem cell lines can essentially be removed using this medium,” said Tenneille Ludwig, the UW-Madison scientist who led the effort to develop the new culture media. “This work helps us clear some of the major hurdles for using those cells therapeutically.”
Much work remains to be done before Thomson and others fully understand the chromosome stability of stem cells during long-term culture, and that challenge cuts to the heart of current restrictions on federally funded stem-cell research.
In August 2001, President Bush imposed a compromise enabling federal funds to be used for the first time to study a limited number of stem cell lines. The rights to some of those lines were held by the Wisconsin Alumni Research Foundation, a private, non-profit patent and license affiliate of the UW-Madison. It was WARF that created WiCell to continue stem-cell research, using only those approved lines.
As the research by Thomson, Ludwig and others now demonstrates, however, more work should be focused on WA 15 and WA 16 – the lines that are free of animal contamination. Unless we learn more about those lines, stem cell research in the United States could be dramatically delayed.
“Derivation and culture in serum-free, animal product-free, feeder-independent conditions means that new human cell lines could be qualitatively different from the original lines, and makes current public policy in the United States increasingly unsound,” concluded the paper published in Nature Biotechnology.
Thomson and his team are not alone. Researchers across the United States have called for opening up new stem cell lines for federal research funding because the older lines have been shown to accumulate genetic mutations. Those mutations don’t prevent research, but they stand in the way of future clinical uses. New lines would also provide additional genetic diversity to the mix.
Policymakers in the United States can sit back and wait for the Hwang Woo-suks of the research world to undertake research that challenges credibility, or they can empower credible researchers at home to do the work. The answer should be clear.
–Still is president of the Wisconsin Technology Council. He is the former associate editor of the Wisconsin State Journal in Madison.
