V. Avellanaadalid et al., EXPANSION OF RAT OLIGODENDROCYTE PROGENITORS INTO PROLIFERATIVE OLIGOSPHERES THAT RETAIN DIFFERENTIATION POTENTIAL, Journal of neuroscience research, 45(5), 1996, pp. 558-570
The limited availability of enriched populations of oligodendroglial p
rogenitors has impeded the exploration of the complex spatio-temporal
mechanisms which dictate the chemical ''language'' of their biology, W
e have developed a technique to prepare homotypic aggregates of oligod
endrocyte progenitors called ''oligospheres.'' These were obtained usi
ng various approaches (sieving, Percoll gradient separation and differ
ential adhesion) to purify oligodendroglial progenitors from newborn r
at brain, Culturing cells in a mixture of N1 defined medium and condit
ioned medium from the B104 neuronal cell line in the absence of adhesi
ve substrate allowed to expand routinely and extensively for several m
onths, the oligodendrocyte progenitor population, Under these conditio
ns, the resulting population consisted of 98% GD3-positive/GFAP-negati
ve cells. After dissociation and plating on polyornithine coated subst
rates, in the presence of low (2%) or high (20%) serum, oligosphere-de
rived oligodendrocyte progenitors were induced to differentiate into G
alC-positive oligodendrocytes or GFAP-positive astrocytes, respectivel
y, When transplanted into the newborn shiverer mouse brain, oligospher
es were able to provide a focal reservoir of migrating and myelinating
cells, Oligospheres are thus ideal tools for exploring the biological
and molecular events of the oligodendrocyte lineage both in vitro and
in vivo. (C) 1996 Wiley-Liss, Inc.