A developmental analysis of oligodendroglial integrins in primary cells: Changes in αv-associated β subunits during differentiation

We have examined the expression of integrins on primary oligodendroglial cells during the differentiation of the proliferative oligodendrocyte precursor (O-2A progenitor) cell to the postmitotic oligodendrocyte. Cells of the oligodendrocyte lineage expressed a limited repertoire of integrins: α6β1 and αv integrins including αvβ1, αvβ3 and αvβ5, as well as a potentially novel integrin αvβ80kDa. Integrin expression was developmentally regulated; during differentiation αvβ1 was reduced and αvβ5 upregulated. These results suggest that laminin and vitronectin are important extracellular matrix ligands for oligodendrocytes, and provide a rational explanation for previous observations that RGD peptides inhibit the expression of myelin-specific genes. They also suggest a simple model by which switching of integrin β subunits might regulate differentiation. As chimeric β1 integrins with a β5 cytoplasmic domain support proliferation less well than normal β1 integrins the switch from αvβ1 to αvβ5 might play a key instructive role in the cessation of proliferation and subsequent differentiation.