Volume 17, Number 19,
Issue of October 1, 1997
pp. 7228-7236
Copyright ©1997 Society for Neuroscience
Phenotypic Alteration of Astrocytes Induced by Ciliary
Neurotrophic Factor in the Intact Adult Brain, As Revealed by
Adenovirus-Mediated Gene Transfer
Received March 26, 1997; revised June 12, 1997; accepted July 10, 1997.
Fabrice Lisovoski1,
Said Akli2,
Elise Peltekian1,
Emmanuelle Vigne3,
Georg Haase2,
Michel Perricaudet3,
Patrick A. Dreyfus1,
Axel Kahn2, and
Marc Peschanski1
1 Faculté de Médecine, Institut National de
la Santé et de la Recherche Médicale Unité 421, Institut Mondor de Médecine Moléculaire, Institut Gustave
Roussy, 94010 Créteil Cedex, France, 2 Institut
National de la Santé et de la Recherche Médicale
Unité 129, Institut Cochin de Genetique Moleculaire, 75014 Paris,
France, and 3 Centre National de la Recherche Scientifique,
Unité de Recherche Associée 1301/Rhône-Poulenc Rorer,
Institut Mondor de Médecine Moléculaire, Institut Gustave
Roussy, 94805 Villejuif Cedex, France
Synthesis of the ciliary neurotrophic factor (CNTF) and its
specific receptor (CNTFR
) is widespread in the intact CNS, but potential biological roles for this system remain elusive.
Contradictory results have been obtained concerning a possible effect
on the morphological and biochemical phenotype of astrocytes. To
reassess this question, we have taken advantage of adenovirus-mediated gene transfer into the rat brain to obtain the local release of CNTF.
Stereotaxic administration of CNTF recombinant adenovirus vectors into
the striatum led to phenotypic changes in astrocytes located in regions
that were related axonally to striatal neurons at the injection site.
Astrocytes appeared hypertrophied and displayed an increase in both
GFAP and CNTF immunoreactivity. This response was observed up to 5 weeks after injection, the longest time studied. It was not observed
after the administration of a control vector. The methodology used in
the present study, allowing us to analyze the effect of the factor in
areas remote from the injection site, has provided conclusive evidence
that CNTF affects the astroglial phenotype in the intact CNS. The
characteristics of these effects may explain why contradictory results
have been obtained previously, because this signaling system seems to
have a low efficiency and therefore requires a high local concentration
of the factor close to the target cells. One might speculate as to the
involvement of a CNTF astroglio-astroglial signaling system in the
organized response of a population of astrocytes to changes in CNS
homeostasis detected locally, even by a single cell.
Key words:
CNTF;
adenovirus vector;
astroglial differentiation;
in vivo gene transfer;
astrogliosis