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Humoral
and contact interactions in astroglia/stem cell
co-cultures in
the course of glia-induced neurogenesis .Zs. Környei 1*, V.
Szlávik 1, B. Szabó 2, E. Gócza 3, A.
Czirók 2, and E. Madarász 1 1
Institute of Experimental Medicine, Budapest, Hungary; 2
Department of Biological Physics, Eötvös University, Budapest, Hungary;
3 Agricultural Biotechnology Center, Gödöllő,
Hungary |
|
.
Astroglial cells support or restrict the migration and
differentiation of neural stem cells depending on the developmental stage of the
progenitors and the physiological state of the astrocytes. In the present study
we show that astroglial cells instruct non-committed, immortalized
neuroectodermal stem cells to adopt a neuronal fate, while they fail to induce
neuronal differentiation of embryonic stem cells under similar culture
conditions. Astrocytes induce neuron formation by neuroectodermal progenitors
both through direct cell-to-cell contacts and via short-range acting humoral
factors. Neuron formation takes place inside compact stem cell assemblies formed
30-60 hours after the onset of glial induction. Statistical analyses of
time-lapse microscopic recordings show that direct contacts with astrocytes
hinder the migration of neuroectodermal progenitors, while astroglia-derived
humoral factors increase their motility. In non-contact co-cultures with
astrocytes, altered adhesiveness prevents the separation of frequently colliding
neural stem cells. In contact co-cultures with astrocytes, on the other
hand, the restricted migration on glial surfaces keeps the cell-progenies
together resulting in the formation of clonally proliferating stem cell
aggregates. The data indicate that in vitro maintained parenchymal
astrocytes i, secrete factors, which initiate neuronal differentiation of
neuroectodermal stem cells and ii, provide a cellular microenvironment where
stem cell/stem cell interactions can develop and the sorting out of the future
neurons can proceed. In contrast to non-committed progenitors, postmitotic
neuronal precursors leave the stem cell clusters, indicating that astroglial
cells selectively support the migration of maturing neurons as well as the
elongation of neurites.
.
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Glia,
2005 Feb;49(3):430-44. |
Key
words:
neural stem cell, astroglia, embryonic stem cell, differentiation,
migration |
.
Supplemental
movies:
.
Non-induced
NE-4C immortalized neuroectodermal stem cells on poly-L-lysin coated
plastic surface:
Movie1.mov (16.4
MB), Movie1.mpeg
(2.1
MB)
Field
of view: 150um X 130um. Duration of recording: 48 hours. Number of frames:
289 (10 min/frame). In
monocultures of non-induced NE-4C cells the daughter cells depart from
each other after each division. Colored trajectories show the migratory
routes of consecutive generations of a representative NE-4C
neuroectodermal stem cell. The cells were seeded onto poly-L-lysine coated
plastic culture dish in serum free medium. The 48-hour long movie starts
at 30 min. after attachment to the substrate. |
|
|
Aggregate
formation by an NE-4C neuroectodermal cell plated onto astroglial
monolayer: Field
of view: 70um X 80um. Duration of recording: 86 hours. Number of frames:
653 (10 min/frame). On
the surface of astrocytes, the progenies of individual NE-4C neural stem
cells did not separate from each other in the course of repeated cell
divisions. Synchronized divisions seem to result in a periodic loosening
and compaction of the aggregate. The movie starts 30 min. after attachment
to the substrate and lasts for 86 hours. |
|
|
On
the surface of astrocytes NE-4C neuroectodermal stem cells expand
neurite-like processes: Field
of view: 106um X 92um. Duration of recording: 2 hours and 40 minutes.
Number of frames: 34 (5 min/frame). |
|
|
Migration
of NE-4C neural stem cell derived neuronal precursors on the surface of
astrocytes: Field
of view: 216um X 108um. Duration of recording: 60 hours. Number of frames:
364 (10 min/frame). |
|
|
Neurite
elongation by an NE-4C derived neuron on the surface of astroglial
cells: Field
of view: 130um X 170um. Duration of recording: 17 hours. Number of frames:
364 (10 min/frame). |
|
|
Aggregate
formation by NE-4C neuroectodermal cells in non-contact co-cultures with
astrocytes: Field
of view: 440um X 320um. Duration of recording: 48 hours. Number of frames:
579 (5 min/frame). |
|
Other
Movies:
|
Migration
of an NE-4C neural stem cell derived neuronal precursor on the surface of
astrocytes: Movie7.mov
(7,3 MB) Field
of view: 160um X 200um. Duration of recording: 30 hours and 30 minutes.
Number of frames: 178 (10 min/frame). |
|
|
Development
of a neurogenic NE-4C cell cluster on the surface of astrocytes: Movie8.mov
(17 MB),
Movie8.mpeg
(11,9
MB) Watch
the extensive neurite-elongation at 70 hour. |
|
|
Aggregation
of NE-4C cells in non-contact co-cultures with
astrocytes: Movie9.mov
(27.5 MB), Movie9.mpeg
(14,3
MB) Field
of view: um 1200X 870um. Duration of recording: 72 hours. Number of
frames: 864 (5 min/frame). |
|
Related
documents:
Posters
at 15th Biennal Meeting of International Society of Developmental Neuroscience,
2004,
* Dynamics
of astroglia-induced neurogenesis
pdf
* Expression
of neurogenic and region specific genes during in vitro induced neurogenesis of
NE-4C neuroectodermal cells
pdf
* Gap
junction communication by NE-4C neuroectodermal stem cells pdf
Poster
at IBRO International Workshop on Neuronal Circuits, 2004,
* Astroglia
– neural stem cell interaction
pdf
Poster
at Satellite Symposium to the Sixth IBRO World Congress of Neuroscience, 2003,
* Astroglia
– stem cell interaction
pdf
Poster
at Faseb Summer Research Confererences / Retinoids, 2002,
* Astroglial
cells support the neuronal differentiation of immortalized neuroectodermal
progenitor cells
pdf
Related
sites:
*
Long-term automated live cell
microscopy at Dept. of Biological Physics, Eotvos University, Budapest,
Hungary
* Laboratory of Neural Cell
Biology at Institute of Experimental Medicine, Budapest, Hungary
