Transplanted "liver buds" self-organized to grow into functional organs, staving off death in mice with liver failure By Monya Baker and Nature magazine This stem cell approach may one day help patients waiting for liver transplants. Image: Flickr/Tareq Salahuddin Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way... Read More Transplanting tiny 'liver buds' constructed from human stem cells restores liver function in mice, researchers have found. Although preliminary, the results offer a potential path towards developing treatments for the thousands of patients awaiting liver transplants every year. The liver buds, approximately 4 mm across, staved off death in mice with liver failure, the researchers report this week in Nature. The transplanted structures also took on a range of liver functions secreting liver-specific proteins and producing human-specific metabolites. But perhaps most notably, these buds quickly hooked up with nearby blood vessels and continued to grow after transplantation. The results are preliminary but promising, says Valerie Gouon-Evans, who studies liver development and regeneration at Mount Sinai Hospital in New York. This is a very novel thing, she says. Because the liver buds are supported by … Continue reading →

Scientists in Japan said they had grown human liver tissue from stem cells in a first that holds promise for alleviating the critical shortage of donor organs. Creating lab-grown tissue to replenish organs damaged by accident or disease is a Holy Grail for the pioneering field of research into the premature cells known as stem cells. Now Takanori Takebe of the Yokohama City University Graduate School of Medicine and a team reported Wednesday in the journal Nature that they grew tissue "resembling the (human) adult liver" in a lab mouse. They first created induced pluripotent stem (iPS) cells which they mixed with other cell types and coaxed into "liver buds" -- the precursor clusters that develop into a liver. The buds, each about five millimetres (0.2 inches) big, were then transplanted onto a mouse brain, where they were observed transforming into a "functional human liver" complete with blood vessels, the scientists wrote. "To our knowledge, this is the first report demonstrating the generation of a functional human organ from pluripotent stem cells," said the report. The technique has yet to be tested in humans, but serves as an important proof of concept, it added. Stem cells are infant cells that … Continue reading →