发信人: Marble (小石头哥哥), 信区: Biology
标 题: MCBJC(Neurogenesis/adult neural stem cell)
发信站: The unknown SPACE (Mon Apr 7 14:13:53 2003), 站内信件

this Nature paper (2002 417:39) addressed the mechanisms that
control fate of neural stem cells. astrocytes have been
thought merely as supportive cells in the central nervous
system, however, this work has demonstrated that astrocytes
isolated from adult hippocampus, but not spinal chord,
promoted neurogenesis (i.e., neuron fate) of the adult neural
stem cells in cell culture. this study has highlighted the
effects of the environment on the specification of stem cells.
for stem cell research, many labs try to identify the key
features for cells that have "stemness", and how they could
be induced to differentiate into different lineages, and
whether different lineages could "transdifferentiate". it is
rather new area with many things unknown, and even experiments
that had doubt on previously published data could get onto
top journals.

my questions for this paper:
1. what are the methodology they used to study differentiation
of neural stem cells? do you think there might be flaw for such
study (for example, primarily in vitro cell culture; counting
cells with differentiation marker really means that the cells
have differentiated into functional states)?
2. they proposed that cell-attached and diffusible factors from
astrocytes are essential to the neurogenesis of adult stem
cells. how would you like to identify and characterize such
factors biochemically and genetically?
3. btw, Dr. Song also had a publication on Nat Neuro 2002
5:438 in which he demonstrated that these stem cells had
functionally integrated into the system using electrophysiology.
i would think that in vivo transplantation and a long-term
project chasing the fate of the neural stem cells would be
more convincing.



--
※ 修改:．Marble 于 Apr 7 16:15:19 修改本文．[FROM: 128.118.]
※ 来源:．The unknown SPACE bbs.mit.edu．[FROM: 128.118.]