Transcriptional Characterization of Glioma Neural Stem Cells Diva ...

2.2 Neural Stem Cells Introduction
differentiation to neurons, NS cells had to be plated on laminin-coated plates
in basal medium withdrawing first EGF and then FGF2 in this order, since so
long as EGF and FGF2 are supplied together no cell differentiation can occur
and cells continue to self-renew. For differentiation to astrocytes, NS cells were
exposed to 1% serum without EGF and FGF2 or exposed to BMP4 and LIF
[399]. For differentiation to oligodendrocytes, the culture conditions involved
re-culturing on laminin coated dishes in medium containing FGF2, PDGF
and forskolin first, adding T3 and ascorbic acid later, a procedure known to
promote the differentiation and survival of oligodendrocytes [165]. Under these
conditions, NS cells efficiently differentiated into oligodendrocytes, astrocytes
and neurons, with similar outcomes seen for NS cells derived from fetal mouse
brain, altogether demonstrating that oligodendrocyte progenitor proliferation
and differentiation seems to be preserved in adult mouse-derived NS cells.
Importantly, the ability for oligodendroglial differentiation is maintained after
transplantation. Therefore, the differentiation spectrum of these NS cells is
not restricted to neurons and astrocytes but also extends to oligodendrocytes
[165,399].
Figure 2.9: Roles of EGF and FGF2 in the derivation and maintenance of NS
cells. Fetal forebrain progenitors or ES cell-derived neural progenitors (green) can
be converted into NS cell lines (yellow) using a combination of EGF with FGF2.
Once established, NS cells can be maintained in added EGF alone, whereas in FGF2
alone, they undergo differentiation (blue) and apoptosis. Adapted from Pollard et al
2006 [403] and Conti et al 2005 [107].
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