In vivo analysis of glial cell phenotypes during a viral demyelinating disease in mice

The O4 antibody stains oligodendrocytes, type 2 astrocytes and oligodendrocyte precursors cultured from perinatal rat and mouse as well as a majority of O-2A progenitors cultured from 7-d-old rat optic nerve (Sommer and Schachner, 1981; Schachner et al., 1981; $ommer, I., and M. Noble, unpublished observations; Trotter and Schachner, 1989) . Clones derived from single O-2A progenitor cells from neonatal optic nerve or brain often contain multipolar 04 + G C -cells capable of proliferation and differentiation (Dubois-Dalcq, 1987; McMorris and Dubois-Dalcq, 1988) . Similar 04+ cells have also been isolated from adult rat optic nerve. These cells proliferate slowly and give rise in vitro to oligodendrocytes and type 2 astrocytes; they have been termed O-2A adult progenitor cells (Wolswijk and Noble, 1989) . Cells with similar phenotype (04 + G F A P -G C -) have also been isolated from adult mouse spinal cord. Precursor cells of oligodendrocytes have been identified in vivo in the developing white matter using antibody to GD3 gangliosides (Levine and Goldman, 1988; Reynolds and Wilkin, 1988) but until now 04 + precursor of oligodendrocytes had not been visualized in adult CNS in vivo.