Looking Below the Surface: Stem Cell Behavior in Real Time

Scientists have for the first time watched and manipulated stem cells as they regenerate tissue in an uninjured mammal, Yale researchers report July 1, 2012, online in the journal Nature. Using a sophisticated imaging technique, the researchers also demonstrated that mice lacking a certain type of cell do not regrow hair. The same technique could shed light on how stem cells interact with other cells and trigger repairs in a variety of other organs, including lung and heart tissue. Valentina Greco, assistant professor of genetics and of dermatology at Yale School of Medicine, and her team focused on stem cell behavior in the hair follicle of the mouse. The accessibility of the hair follicle allowed real-time and non-invasive imaging through a technology called 2-photon intravital microscopy. Using this method, Panteleimon Rompolas, a post-doctoral fellow in Greco's lab and lead author of this paper, was able to study the interaction between stem cells and thei!
r progeny, which produce all the different types of cells in the tissue. The interaction of these cells with the immediate environment determines how cells divide, where they migrate and which specialized cells they become. The technology allowed the team to discover that hair growth in mice cannot take place in the absence of connective tissue called mesenchyme, which appears early in embryonic development.
The study was funded by an Alexander Brown Coxe postdoctoral fellowship. This work was supported in part by the American Skin Association and the American Cancer Society and the Yale Rheumatologic Disease Research Core Center and the National Institutes of Health.
Other Yale authors include Elizabeth Deschene, Giovanni Zito, David G. Gonzalez, Ichiko Saotome and Ann M. Haberman.
Credits
Produced by Yale School of Medicine's Office of Institutional Planning and Communications (medicine.yale.edu/ipc)
Producer/director: Michael Fitzsousa
Stem cell videos courtesy of Panteleimon Rompolas
Opening graphic: Jennifer Stockwell
Two-photon microscope diagram © 2010 LaVision BioTec GmbH, Germany
Skin illustration © 2008 Terese Winslow; U.S. government has certain rights
Special thanks: Kirsten Cartoski, Wes Choy, Doug Forbush, Yale Broadcast and Media Center