44
microsphere fraction cells had visibly more dense
neurofilaments and A2B5(+) neurons (not shown). In
monolayers, more neuronal processes were found that
contained filaments positive for the polyclonal antisera
than for NF1, and processes that contained filaments that
were NF1(+) were almost always NF-M(+) as well. Thus, the
patterns of neuronal and glial intermediate filaments
appeared identical in purified and unpurified cells when
grown on a substratum of glass.
The pattern of neurofilament immunostaining was very
different, however, in purified versus unpurified cultures
when grown on a substratum of polyornithine (Fig.2-9). As
stated above, only a network of neurons survived when
unpurified cells were cultured on polyornithine. As in
neurons cultured on glass, many of the neurons on
polyornithine contained neurofilaments. Purified cultures,
on the other hand, degenerated on polyornithine and
contained a paucity of neurofilaments. The few cells that
survived and produced neurofilaments (or had them at the
start) were presumably those A2B5(-)/NF-M(+) cells (see
above) that eluted in the purified population.
Galactocerebroside Expression In Vitro
A monoclonal antibody specific for the membrane
molecule galactocerebroside (GC) was used to study the
development of oligodenrocytes in cultures of purified and
unpurified tectum cells. No GC(+) cells were present in