Adult stem cell talents grow

 作者:郈参     |      日期:2019-03-06 08:03:21
By Greg Miller As the US President, George W. Bush, deliberates over whether to allow federal funding for research on embryonic stem cells, evidence of the remarkable potential of adult stem cells has continued to pile up. Researchers in Britain have added another talent to adult stem cells’ growing repertoire, announcing that such cells taken from bone marrow can develop into kidney cells. The bone marrow stem cells are immature blood cells and have already been shown to transform into liver, nerve and muscle cells. Both adult and embryonic stem cells have enormous medical potential due to their ability to mature into a wide range of different tissues, which could then be transplanted. However, ethical considerations have prompted many to argue that research on embryonic stem cells, which requires the destruction of human embryos, should not receive US government support. Bush must weigh the ethical problems of using embryonic stem cells against their healing potential and so a great deal hinges on whether adult stem cells can be shown to be as versatile as their less mature cousins, embryonic stem cells. The latter are thought to be able to develop into any type of cell. The UK team examined kidney biopsy tissue from eight male transplant recipients who had received kidneys from female donors. Many cells from the transplanted kidneys contained a Y chromosome, which only appears in males, indicating the cells must have originated within the male transplant recipients. This does not prove directly that the kidney cells came from bone marrow stem cells, but that is the most plausible explanation, says team member Richard Poulsom. He and his colleagues did a parallel study in mice that backs that interpretation. They found kidney cells with Y chromosomes in female mice that had received bone marrow transplants from male mice. These cells looked normal and manufactured typical kidney cell proteins. Poulson says these results suggest doctors may one day be able to use stem cells from a patient’s own blood marrow to restore disease-ravaged kidneys. But Poulson thinks research on embryonic stem cells should continue. “It’s such early days for stem cell research. You need to study both to see what they can do.” Many in the scientific community agree. A group of 80 Nobel laureates recently wrote to Bush, urging him to back funding for embryonic stem cell research. The US National Institutes of Health, which says it has no official position on funding for stem cell research, issued a report last week that emphasised the importance of understanding both embryonic and adult stem cells. But while many scientists, the majority of the US public and a growing number of politicians, including many Republicans, support federal funding for the research, the president is being pulled in the opposite direction by anti-abortion campaigners and some religious leaders. On Monday, the leader of the world’s Roman Catholics,