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An interesting finding concerning glial development in
culture is the lack of appearance of oligodendrocytes in
culture. These results using an antibody for the marker
galactocerebroside (GC) essentially confirm the results of
Linser and Perkins (1987a) who failed to find cells
positive for the oligodendrocyte markers myelin basic
protein and S-100 (Linser, 1985). This is in contrast to
cultures made from day 12 or 13 tectum cells where GC(+)
cells are present and develop in vitro (Chapter III). Thus
it seems that either future cellular interactions were
disrupted that were required for oligodendrocytes to
develop, or that the culture conditions did not contain
some growth factor(s) that was required earlier in
development. It should be noted that these results are in
contrast to those with rat brain cells where
oligodendrocytes appear in cultures that do not contain
them initially (embryonic day 10) on time with those that
appear in vivo 13-14 days later (Abney, Bartlett, and Raff,
1981) .