The furore on Capitol Hill over Planned Parenthood has stoked a debate about the use of tissue from aborted foetuses in medical research, but U.S. scientists have been using such cells for decades to develop vaccines and seek treatments for a host of ailments, from vision loss and neurological disorders to cancer and Aids.
Tissue would otherwise be thrown out
Anti-abortion activists set off the uproar by releasing undercover videos of Planned Parenthood officials that raised questions of whether the organisation was profiting from the sale of foetal tissue. Planned Parenthood has denied making any profit and said it charges fees solely to cover its costs.
University laboratories that buy such cells strongly defend their research, saying tissue that would otherwise be thrown out has played a vital role in lifesaving medical advances and holds great potential for further breakthroughs.
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Foetal cells are considered ideal because they divide rapidly, easily adapt to new environments and are less susceptible to rejection than adult cells when transplanted.
"If researchers are unable to work with foetal tissue, there is a huge list of diseases for which researchers would move much more slowly, rather than quickly, to find their cause and how they can be cured," Stanford University spokeswoman Lisa Lapin said in an email.
From 2011 through 2014 alone, 97 research institutions — mostly universities and hospitals — received a total of $280 million in federal grants for foetal tissue research from the National Institutes of Health. A few institutions have consistently received large shares of that money, including Yale, the University of California and Massachusetts General Hospital, which is affiliated with Harvard.
The U.S. government prohibits the sale of foetal tissue for profit and requires separation between researchers and the women who donate foetuses. Some schools go further, requiring written consent from donors.
Many major universities declined to make scientists available for interviews about their foetal tissue work, saying they fear for the researchers' safety because the issue is so highly charged. The Planned Parenthood uproar led to a failed attempt by Republicans to strip the organisation of federal funding.
Researchers use foetal tissue to understand cell biology and human development. Others use it to look for treatments for Aids. Research on spinal cord injuries and eyesight-robbing macular degeneration involves transplanting foetal cells into patients. European researchers recently began putting foetal tissue into patients' brains to try to treat Parkinson's, a strategy that previously had mixed results.
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Some scientists are looking for alternatives to foetal tissue, such as using adult cells that have been "reprogrammed" to their earlier forms. But those techniques are still being refined, and some fields are likely to remain reliant on foetal tissue, such as the study of foetal development.
Vaccines have been one of the chief public benefits of foetal tissue research. Vaccines for hepatitis A, German measles, chickenpox and rabies, for example, were developed using cell lines grown from tissue from two elective abortions, one in England and one in Sweden, that were performed in the 1960s.
German measles, also known as rubella, "caused 5,000 spontaneous abortions a year prior to the vaccine," said Dr Paul Offit, an infectious-disease specialist at Children's Hospital of Philadelphia. "We wouldn't have saved all those lives had it not been for those cells."
Foetal tissue was "absolutely critical" to the development of a potential Ebola vaccine that has shown promise, said Dr Carrie Wolinetz, an associate director at NIH, which last year handed out $76 million for work involving foetal tissue, or 0.2 percent of the agency's research budget.
Scientists are also using foetal tissue to try to identify substances in adults that could be early warning signs of cancer, said Dr Akhilesh Pandey, a molecular biologist at Johns Hopkins University.
Tremendous value in driving discoveries
Experts at MIT and other research centres use foetal tissue to implant the human immune system into mice, as a way to study diseases without employing people as test subjects. They add tumours to study the immune system's response, then test cancer treatments out on the mice.
"This eventually will provide a benefit to society," said Jianzhu Chen, an immunology professor and researcher at MIT.
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At Stanford, foetal tissue has been used to study Huntington's disease, "bubble boy disease" and juvenile diabetes. Foetal brain calls are now being used there in research on autism and schizophrenia.
After the release of the undercover videos, Colorado State University conducted an ethics review and suspended its dealings with one vendor. But it is pressing ahead with its HIV research with foetal tissue.
"Our position is this research has such tremendous value in driving discoveries that could be done no other way," said Alan Rudolph, university vice president of research.
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Image: Planned Parenthood from Shutterstock