Purchase this article with an account.
Michael R. Böhm, Sarah Pfrommer, Carolyn Chiwitt, Harutyun Melkonyan, Solon Thanos; Fabrication and Use of Cellular Bioreactors to Support Lengthy Regeneration within the Adult Optic Nerve. Invest. Ophthalmol. Vis. Sci. 2012;53(14):2974.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Injuries to the optic nerve (ON) are still not reparable and result in retrograde and anterograde degeneration. It is inevitable to work on strategies for assessing the mechanism of failure to regenerate axons within the ON. One strategy is the implantation of neural progenitor cells (NPC), which might produce growth promoting factors and pave the microenvironment, thus allowing for nerve regeneration. The study provides a method to produce and use rat NPC, therefore triggering regeneration of axons.
Using a rat model of ON injury, we aimed to examine whether intravitreally or intraneurally applied NPCs support axonal growth. NPCs from the prospective retina and the rostral neural tube retain their stem cell feature and can be propagated and expanded in vitro. NPCs (rat) were isolated at embryonic days E13 to E15. They were cultivated in vitro and characterized by immunohistochemistry (e.g. nestin). Completely cut or crush of ON and injection of NPCs which overexpressed crystalline beta b-2 (crybb-2) were studied. One month postsurgery anterograde and immunohistochemical staining of the ON was applied. RGC-numbers were examined with retrograde labeling using fluorogold.
Cultured or implanted NPCs produce neurotrophic factors. After implantation into the cut ON or the vitreous they produce and secrete the same factors (neurotrophins, crystallins, trophic factors, metalloproteases), at the site of injury. NPCs are used as living "cell biofabrics" to stimulate neuroregeneration, in particular after overexpressing crybb-2. The data obtained indicate that implanted NPC remain within the vitreous body over weeks, thereby migrating into other ocular compartments causing specific cellular responses in neurons and glial cells. Cut axons pass through the zone of injury to enter the distal optic nerve over long distances. Immunohistochemical data obtained from serial sections through the proximal, injured and distal optic nerve permitted to count the axons and examine the incidence of axonal regeneration which is below 10% of the total injured population.
We conclude that paving of the distal optic nerve environment with NPCs and stimulation of retinal ganglion cells with NPC-derived factors is a suitable method to study regeneration of cut axons.Supported by the IZKF-Muenster.
This PDF is available to Subscribers Only