Cell-based remyelinating therapies in multiple sclerosis: evidence from experimental studies.
OBJECTIVE
Spontaneous remyelination occurs in the central nervous system of patients with multiple sclerosis. However, this process is not robust enough to promote a functional and stable recovery of the myelin architecture. The development of cell-based therapies, aimed at promoting multifocal remyelination, is therefore foreseen.


RESULTS
Several experimental cell-based strategies aimed at replacing damaged myelin-forming cells have been developed in the last few years. However, most of these therapeutic approaches - although consistently able to form new myelin sheaths at the transplantation site - are unfeasible owing to the mutifocality of the demyelinating process in multiple sclerosis patients and the inability to grow and produce large numbers of differentiated myelin-forming cells in vitro. Stem cell-based therapies that partially overcome these limitations have been proposed recently.


CONCLUSIONS
Stem cell-based remyelinating therapies can be considered a plausible alternative strategy in immune-mediated demyelinating disorders. However, before any potential applications in patients with multiple sclerosis can be envisaged, it is necessary to confront the following preliminary, and still unsolved, questions: (1) the ideal stem cell source for transplantation; (2) the most appropriate route of stem cell administration; and, last but not least, (3) the best approach for achieving an appropriate, functional and long-lasting integration of transplanted stem cells into the host tissue.
Pluchino
Stefano
S
Neuroimmunology Unit - Department of Biotechnology (DIBIT) and Department of Neurology and Neurophysiology, San Raffaele Scientific Institute, Milan, Italy.
Furlan
Roberto
R
Martino
Gianvito
G
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000502:physiology; D002454:Cell Differentiation; D064987:Cell- and Tissue-Based Therapy; D006801:Humans; D009103:Multiple Sclerosis / Q000503:physiopathology* / Q000628:therapy*; D009413:Nerve Fibers, Myelinated; D009416:Nerve Regeneration / Q000502:physiology*; D009457:Neuroglia / Q000502:physiology / Q000637:transplantation*; D009830:Olfactory Bulb / Q000166:cytology / Q000637:transplantation; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology / Q000502:physiology