N-cadherin influences migration of oligodendrocytes on astrocyte monolayers

Oligodendrocyte cell migration is required for the development of the nervo us system and the repopulation of demyelinated lesions in the adult central nervous system. We have investigated the role of the calcium-dependent adh esion molecules, the cadherins, in oligodendrocyte-astrocyte interaction an d oligodendrocyte progenitor migration. Immunostaining demonstrated the exp ression of N-cadherin on the surfaces of both oligodendrocytes and astrocyt es, and oligodendrocyte-like cells adhered to and spread on N-cadherin subs trates. The blocking of cadherin function by antisera or specific peptides reduced adhesion of oligodendroglia to astrocyte monolayers, diminished con tact time between oligodendrocyte processes and individual astrocytes, and significantly increased the migration of oligodendrocyte-like cells on astr ocyte monolayers. Furthermore, a soluble cadherin molecule without adhesive properties increased oligodendroglial proliferation on various extracellul ar matrix substrates. These data suggest that cadherins are at least partia lly responsible for the poor migration-promoting properties of astrocytes a nd that decreasing cell-cell adhesion might effect repopulation of demyelin ated multiple sclerosis lesions by oligodendrocyte progenitors.