Combinatorial Therapy Stimulates Long-Distance Regeneration, Target Reinnervation, and Partial Recovery of Vision After Optic Nerve Injury in Mice - International Review of Neurobiology - page 165

complex aspects of vision can be restored. However, these results provide
the first evidence that, in principle, some functional recovery may be pos-
sible in patients.
8. CONCLUSIONS
The optic nerve, long viewed as a classic example of a CNS pathway
that cannot grow back when injured, now appears to be capable of long-
distance regeneration, remyelination, target reinnervation, and at least a
modest level of functional recovery in mature mice. Although the methods
used to achieve this outcome are not suitable for use in the clinic, modifi-
cations of these approaches might be. Clinical trials have demonstrated the
safety and partial efficacy of gene therapy in the eye for retinal degeneration
( Bainbridge et al., 2008 ), and it is possible that viral vectors designed to
mimic the treatments found to be effective in mice could be tested in pa-
tients with acute optic nerve damage. For example, adeno-associated viruses
could be designed to increase retinal levels of Ocm and decrease expression
of PTEN in RGCs for a limited duration. Although the development of op-
timal treatments is likely to be several years away, the progress that has been
achieved so far lends encouragement to the possibility that optic nerve repair
may one day be possible.
ACKNOWLEDGMENTS
We are grateful for the support of the National Eye Institute (EY05690 to L. I. B.), CDMRP/
Department of Defense (DM102446 to L. I. B.), The Dr. Miriam and Sheldon G. Adelson
Medical Research Foundation (to L. I. B.), Coordena¸˜o de Aperfei¸oamento de Pessoal de
N´vel Superior (CAPES, Brazil, to S. d. L.), and the Intellectual and Developmental
Disabilities Research Center (IDDRC) of Children's Hospital (NIH P30 HD018655) for
use of the Histology, Image Analysis, and Animal Behavior Cores.
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