Healthy and viable mice that survive until adulthood have, for the first time, been cloned from adult stem cells. Scientists from Rockefeller University, including Howard Hughes Medical Institute investigator Elaine Fuchs, used cells called keratinocyte stem cells, which represent a new model system for cloning. Keratinocytes come from the skin, making them a particularly attractive stem cell source because of their ready accessibility. One day, they could be used to tailor therapies, as well as to better understand and treat diseases.
Fuchs and her colleague Peter Mombaerts published their laboratories' findings online February 12, 2007, in the Proceedings of the National Academy of Sciences.
A number of laboratories have cloned mice using cumulus cells (cells that surround and support a developing egg) or fibroblasts (connective tissue cells). Others have used cultured neural cells that were generated from embryonic stem cells. While these efforts have been successful, they are also notoriously inefficient.
Because adult stem cells retain the ability to differentiate into multiple cell types, it has long been expected that they may be better sources of nuclear material for the cloning technique used by Fuchs and her colleagues, known as nuclear transfer. Fuchs, Mombaerts, and their coworkers are the first to successfully and reproducibly clone healthy mice from any type of adult stem cell.
The keratinocyte stem cells used by Fuchs are found in a part of the hair follicle called the bulge. They are involved in hair growth and in repairing skin wounds. "Researchers have known about these infrequently dividing cells for some time, but only recently have scientists revealed their potential to self-renew and produce multiple types of cells -- the hallmarks of stem cells," Fuchs explained. Keratinocyte stem cells in the bulge have been successfully cultured in the Fuchs' laboratory. When tested in mice, these cells can produce surfac
Contact: Jennifer Michalowski
Howard Hughes Medical Institute