Cell replacement therapy offers a novel and powerful medical technology. A type of embryonic stem cell, called a neural crest stem cell, that persists into adulthood in hair follicles was recently discovered by Maya Sieber-Blum, Ph.D., of the Medical College of Wisconsin, Milos Grim, MD Ph.D., of Charles University Prague, and their collaborators.
The discovery – reported recently in Developmental Dynamics, a journal of the American Association of Anatomists published by John Wiley & Sons, Inc. – may in many instances provide a non-controversial substitute for embryonic stem cells. Embryonic stem cells are unique, because they can differentiate into any cell type of the body. Their use, however, raises ethical concerns because embryos are being destroyed in the process. In contrast, neural crest stem cells from adults have several advantages: similar to embryonic stem cells, they have the innate ability to differentiate into many diverse cell types; they are easily accessible in the skin of adults; and the patient's own neural crest stem cells could be used for cell therapy. The latter avoids both rejection of the implant and graft- versus-host disease.
Studies in the mouse showed that neural crest stem cells from adult hair follicles are able to differentiate into neurons, nerve supporting cells, cartilage/bone cells, smooth muscle cells, and pigment cells. Preliminary data indicate that equivalent stem cells reside in human hair follicles.
"The goal of our research is to apply neural crest stem cells from adult hair follicles in cell replacement therapy in selected instances," Sieber-Blum says. This may include, spinal cord injury, Parkinson's disease, multiple sclerosis, Hirschsprung's disease, peripheral neuropathies, certain defects of the heart, and bone degeneration. Though promising, this research is still in the animal testing stage. Additional research is required before it could benefit patients.