1. Multiple sclerosis is characterized by areas of demyelination spread throughout the central nervous system, in which the myelin sheaths surrounding axons are destroyed. While therapies aimed at suppressing the autoimmune response, such as β-interferon, may prevent further damage, they cannot repair or replace the lost myelin. To this end, an additional therapy has been proposed, which involves transplanting cells of the oligodendrocyte lineage into the central nervous system.
2. The cell of interest for transplantation is the oligodendrocyte precursor because, unlike the differentiated cell, it is an intrinsically migratory and proliferative cell. In order to optimize the transplant strategy we have investigated the molecular mechanisms that control migration in vitro, so that these mechanisms might be upregulated to maximize cell migration in vivo. We have focused on the integrin family of cell adhesion molecules, known to play a fundamental role in the regulation of migration in other cell types.
3. These studies show that oligodendrocytes express a limited repertoire of integrins consisting of α6β1 and three different αv integrins. α6β1 is expressed throughout development but αv integrins show developmental regulation; differentiation is accompanied by loss of αvβ1 and upregulation of αvβ5.
4. Function-blocking studies show that oligodendrocyte precursor migration in vitro is mediated primarily by the developmentally regulated αvβ1 integrin, but not α6β1 or αvβ3. Taken together with previous evidence that cell migration can be regulated by altering integrin expression, this work suggests that modifying expression levels of αvβ1 on oligodendrocyte precursors may increase the migratory capacity of these cells. If so, this would support a future therapeutic strategy aimed at transplanting genetically modified oligodendrocyte precursors to repair widespread demyelinated lesions.
Diminished Ventral Oligodendrocyte Precursor Generation Results in the Subsequent Over-production of Dorsal Oligodendrocyte Precursors of Aberrant Morphology and Function
