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July 13, 2001 Therapeutic Cloning Advances Quietly In Europe's Biotechnology Laboratories By GAUTAM NAIK Staff Reporter of THE WALL STREETJOURNAL ALICANTE, Spain -- Before showing a visitor his lab one recent night, Bernat Soria whispered a warning: "Some people don't know what we're doing here and could get upset. So you can talk about stem cells, but never use the word human embryo." Less than 10 minutes later, Dr. Soria placed a petri dish under a microscope and there, floating in a reddish liquid, were cells taken from a human embryo. He pointed out how several of these "stem cells" were already starting to become nerve tissue. Others would later turn into heart tissue and beat even while sitting in the petri dish. Dr. Soria, along with a small band of scientists in Europe and the U.S., are quietly approaching a momentous -- and controversial -- moment in science: the harvesting of stem cells from cloned human embryos to treat and perhaps cure diabetes, heart disease and other ailments. The process, known as therapeutic cloning, involves two steps: cloning a human into an embryo, and then using the embryo's stem cells to create fresh tissue that can be transplanted into that person. Stems cells have the almost-magical ability to become a variety of cells, including those that make up muscle, nerve and heart tissue. Stem cells from a cloned embryo are particularly desirable because they are less likely to be rejected by the person's immune system. The cloning goal was brought closer to reality this week after a tiny biotechnology company, Advanced Cell Technology Inc. of Worcester, Mass., said it had begun experiments to clone a human embryo to obtain stem cells. But the second step -- creating useful tissue from human stem cells -- is a lot further along, especially in Europe, where objections to such research aren't as fierce as they are in the U.S. In January, for example, Britain became the first nation to approve therapeutic cloning, albeit with safeguards. Britain doesn't permit "reproductive cloning," in which the cloned embryo would become an actual baby. Scientists also need to obtain a license before they can clone embryos for research, and the embryos must be destroyed after 14 days. The debate in Britain wasn't very contentious. Religious and right-to-life groups lodged protests, and anticloning speeches were made in Parliament. But they were drowned out by two groups eager to bring therapeutic cloning to Britain: patients suffering from debilitating diseases, and scientists seeking to give Britain an edge in this new research area. "When people think about human clones they think about identical copies. They don't think about therapy," says Dr. Soria, a physiologist at the University of Miguel Hernandez who admires Britain's new law. "That's the new frontier." Spain's law is less clear-cut, but Dr. Soria is pushing the envelope as far as he can. His ambition is to use tissue transplantation to find a cure for diabetes. So far, in an article in a scientific journal, he claims to have cured diabetic mice. Now he is trying to do the same with humans. His latest accomplishment -- so far unpublished -- is coaxing a large number of stem cells from human embryos to become insulin- producing cells. If these cells were transplanted into a diabetic patient, they would have the potential to cure the person, Dr. Soria says. "Within three years, I should have a human cell that produces and regulates insulin," he predicts. Dr. Soria began working with stem cells in 1996. But he was galvanized into action in early 1997, when researchers at the Roslin Institute in Scotland introduced the world to Dolly the sheep. By cloning a mammal, the Roslin scientists also gave birth to the idea of cloning human embryos and harvesting their stem cells. In October 1998, Dr. Soria began a series of experiments. He took stem cells derived from a mouse embryo, added various lab chemicals, and converted the cells into insulin-producing cells. Some months later, he transplanted the insulin cells into a diabetic mouse. By the next day, the creature's blood glucose level had normalized -- a sign that enough insulin was being produced. Even a year later, he says, the mouse's glucose level was normal. Dr. Soria met Peter Sharp, a Roslin Institute scientist, at a physiology conference in Spain in September 1999, and the two researchers began to talk about "nuclear transfer," the process that created Dolly. Dr. Soria said he wanted to try it on humans in order to harvest stem cells. It was a daunting challenge. Dr. Soria soon discovered that cloning a human was going to be much harder than cloning a sheep. In creating Dolly, for instance, the Roslin scientists wasted more than 200 eggs. "If you're going to use 100 human eggs you have to think twice," Dr. Soria says. But Dr. Soria remained hopeful. He sent a grant application to the Juvenile Diabetes Foundation under the heading, "Therapeutic Cloning of Human Pancreatic Beta Cells." The New York-based foundation agreed to give him $650,000 for a three-year project as long as he met two conditions: delete the word "cloning" from the proposal, and abandon nuclear-transfer research to focus on stem cells. The reasoning: While human embryo cloning may be useful, it is only relevant if scientists first figure out the mysteries of stem cells. For his project, Dr. Soria picked an unusual partner: Cardion AG, a Germany-based company with some of the toughest rules about embryo research. Cardion had a technique that could kill one group of cells in a lab culture while preserving another. Dr. Soria used chemical agents to change human stem cells into insulin-producing cells -- a significant 20% made the transformation, he says -- and then used Cardion's system to destroy the others. Dr. Soria plans to grow the remaining human insulin cells and, by early next year, see if they can produce enough insulin to cure a diabetic mouse. "If we end up with human [insulin-producing] cells that can be transplanted into a human," he says, "we'd like to do it right away. ... It could happen in three years." One Step Forward, Two Steps Back Scientists hope to use cloning for medical research, but many countries ban the process altogether. Other nations, including the U.S., have yet to pass clear legislation to govern how the technology will be used. Australia Human reproductive cloning was forbidden by law last December; embryo research is illegal in the state of Victoria. United Kingdom The British Parliament is the only legislative body that has explicitly approved therapeutic cloning. Reproductive cloning is banned. The creation of embryos for research purposes has been permitted in the U.K. since 1990. France The 1994 "bioethics" laws forbid all human embryo research. Last month, the government of Lionel Jospin dropped a proposal to allow therapeutic cloning after President Jacques Chirac and advisory groups objected. Germany The Embryo Protection law forbids all human embryo research, but a new National Ethics Commission is studying whether to change the law. Japan Passed a law in 2000 to ban reproductive cloning, but left the door open for creating research embryos, including cloned embryos. U.S. Embryo research is forbidden with federal government funds. Nine states (Fla., La., Maine, Mass., Mich., Minn., N.D., Pa., R.I.) ban all human embryo research. Four states (Calif., R.I., Mich., La.) have laws preventing human cloning. Sources: LeRoy Walters, Georgetown University; Lori Andrews, Chicago-Kent College of Law Write to Gautam Naik at [log in to unmask] SOURCE: Wall Street Journal http://www.wsj.com/ * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn