A research team at the University of Newcastle, UK, in the laboratory of Maya Sieber-Blum, have used a combination of small molecules to convert cells isolated from human skin into Schwann cells, which are the specialized cells that surround and insulate peripheral nerves. Schwann cells also play an integral role in nerve repair. This new protocol, pioneered by Sieber-Blum and her colleagues, generates large and pure populations of Schwann cells. Therefore, this research presents a promising step in the repair of peripheral nerve injuries. This research was published in the journal Development.
Presently the repair of peripheral nerves utilizes nerve grafts from donors whose donated neural tissues are transplanted into patients in order to repair damaged peripheral nerves. Unfortunately, this approach has several disadvantages in that it can often itself cause nerve damage. In this new research study, Motoharu Sakaue, in collaboration with together Dr. Sieber-Blum, who is Professor of Stem Cell Sciences at the Institute of Genetic Medicine in Newcastle, examined the possibility of growing Schwann cells, which are known to promote nerve repair, in the laboratory. To expand these cells, Sieber-Blum and her team isolated stem cells from adult skin and differentiated them into Schwann cells by exposing them to small molecules.
“We observed that the bulge, a region within hair follicles, contains skin stem cells that are intermixed with cells derived from the neural crest – a tissue known to give rise to Schwann cells. This observation raised the question whether these neural crest-derived cells are also stem cells and whether they could be used to generate Schwann cells” said Sieber-Blum.
“We then used pertinent small molecules to either enhance or inhibit pathways that are active or inactive, respectively, in the embryo during Schwann cell differentiation” she said.
By applying this novel approach, Sieber-Blum and others generated large and highly pure populations of human Schwann cells in culture. These cells displayed a morphology characteristic of Schwann cells and they also expressed proteins characteristic of Schwann cells. Sieber-Blum and others further investigated the functionality of these Schwann cells, and showed that they could interact with nerves in culture. “The next step is to determine, for example in animal models of peripheral nerve injury, whether grafts of these Schwann cells are conducive to nerve repair,” the authors said.
This study identifies a biologically relevant and accessible source of cells that can potentially be used for to generate sufficient quantities of Schwann cells and thus offers great potential in the repair of peripheral nerve injuries.