Persistence of multipotential progenitors in the juvenile rat subventricular zone.

The juvenile subventricular zone (SVZ) normally produces oligodendrocytes. To determine whether juvenile SVZ cells are lineage-restricted or whether they remain multipotential, we labeled SVZ cells and characterized their progeny after 1 week in vitro using cell morphology and antigen expression. Heterogeneous clones comprised of retrovirally labeled neurons and astrocytes or astrocytes and oligodendrocytes were observed, as well as homogeneous clones of neurons, astrocytes or oligodendrocytes. Large type-1 astrocyte clones were most common, and mixed oligodendrocyte/type-1-astrocyte clusters represented 15% of the total clusters. Twenty five percent of the total clusters contained at least 1 immature neuron. Of 128 clones, 6-10% contained neurons, astrocytes and oligodendrocytes. From these results we conclude that the juvenile SVZ is a mixture of lineage-restricted, bipotential and multipotential neural progenitors.