October 1, 2022

MORE COMPETITION FOR EMBRYONIC STEM CELLS

 Yet another plastic, proliferating, pluripotent stem cell has been discovered, raising questions about the need for embryonic stem cells as cures for dread diseases. In the latest issue of Nature Biotechnology, scientists at Wake Forest University School of Medicine in North Carolina say that stem cells in the amniotic fluid surrounding babies in the womb can turn into all the major tissue types — without any danger of forming tumours. They also grow just as fast as embryonic stem cells (ESCs).

Since amniotic fluid-derived stem (AFS) cells are not derived from dissected embryos, they carry little ethical baggage. It would also be easy to create thousands of cell lines which could be used to create tissues for regenerative medicine. "If you banked 100,000 specimens, you’d be able to provide cells for 99% of the US population with a perfect match for genetic transplantation," says the lead researcher, Dr Anthony Atala.

Other researchers welcomed the discovery. "If the cells can be extracted from the placenta, it’s a very convenient way of getting large numbers of cell lines that repair all types of cells," says Ian Wilmut, one of Britain’s leading stem cell and cloning experts. And Lyle Armstrong, of the University of Newcastle-upon-Tyne, in the UK, told New Scientist: "It’s likely that therapies will arise from cells like these way before they’re available from ESCs."

In an accompanying commentary, the leading Australian stem cell researcher, Alan Trounson, acknowledges the potential of this development. If confirmed, he says, AFS cells "may become an important source of cells for regenerative medicine given their apparent advantages of accessibility and multipotentiality over embryonic and adult stem cells, respectively… [This] could lead to a new wave of research to demonstrate the cells’ utility in regenerative medicine and in other potential applications such as drug screening, tissue engineering and gene therapy."

Although ethical alternatives to embryonic stem cells appear to be proliferating, stem cell researchers are not about to back away from their insistence on the need to clone human embryos to understand diseases and to test new drugs. Harvard researcher George Daly, who is working on therapeutic cloning, told AP: "While they are fascinating subjects of study in their own right, they are not a substitute for human embryonic stem cells, which allow scientists to address a host of other interesting questions in early human development."