In a study published in the journal Nature, a team of Columbia University Medical Center researchers led by Ellen Lumpkin, PhD, associate professor of somatosensory biology, solves an age-old mystery of touch: how cells just beneath the skin surface enable us to feel fine details and textures.
Touch is the last frontier of sensory neuroscience. The cells and molecules that initiate vision—rod and cone cells and light-sensitive receptors—have been known since the early 20th century, and the senses of smell, taste, and hearing are increasingly understood. But almost nothing is known about the cells and molecules responsible for initiating our sense of touch.
The team showed that skin cells called Merkel cells can sense touch and that they work virtually hand in glove with the skin’s neurons to create what we perceive as fine details and textures.
“These experiments are the first direct proof that Merkel cells can encode touch into neural signals that transmit information to the brain about the objects in the world around us,” Dr. Lumpkin said.
The findings may help scientists understand how aging and certain diseases can diminish our ability to sense touch. They could also lead to new approaches to restore the sense of touch.
Angela Christiano Ph.D. (Columbia University) and Colin Jahoda Ph.D. (Durham University) discuss the findings in this study, obstacles that still lie ahead, and the implications of this study for clinical applications.
At the base of the hair follicle there is a specialized cell compartment called the dermal papilla. Forty years ago it was first demonstrated that rodent dermal papilla cells can induce new hair growth when they are removed from the follicle and transplanted into new recipient skin. Importantly, the cells retain this hair growth inducing potential even after they are expanded in number by growth in cell culture. For regenerative medicine purposes, researchers have been trying for many years to demonstrate that the same properties hold true in human dermal papilla cells, however the catch-22 is that human dermal papilla cells quickly lose their inducing potential when grown in culture.
Recently, as a result of a collaborative effort between Durham and Columbia Universities, Claire Higgins et al., (2013) reported in the Proceedings of the National Academy of Sciences (PNAS), demonstrating for the first time that cultured human dermal papilla cells can induce new hair growth in intact human skin. These findings have many implications, not only in dermatology, but in the tissue and regenerative medicine fields as a whole.
Claire A. Higgins, James C. Chen, Jane E. Cerise, Colin A. B. Jahoda, and Angela M. Christiano (2013) Microenvironmental reprogramming by three-dimensional culture enables dermal papilla cells to induce de novo human hair-follicle growth. PNAS doi: 10.1073/pnas.1309970110
Also reported in the New York Times.