Presenting Author Philadelphia College of Osteopathic Medicine
Introduction: Myo/Nog cells express MyoD, Noggin and brain-specific angiogenesis inhibitor 1 (BAI1). They are critical for eye development and respond to injury and stress in the neonatal and adult retina. Their depletion in the embryo results in eye and retinal malformations. Myo/Nog cells increase in number and migrate to areas of injury in response to stress. Cell death in the retina increases with Myo/Nog cell depletion and decreases with their addition to the vitreous. Here we examine the effects and locations of endogenous and exogenous Myo/Nog cells in mice eyes following the induction of glaucoma.
Methods: The anterior chamber of the right eye of C57BL/6J mice was injected with magnetic microbeads and guided to the iridocorneal angle using a handheld magnet, preventing the outflow of aqueous. Intraocular pressure was measured in both eyes following microbead injection on Days 0, 4, 7, 14, D21, and 28. On D7, three of the four groups were given bilateral injections into the anterior chamber of either PBS, unsorted brain cells, or Myo/Nog cells isolated from the brain. The fourth group did not receive any follow-up injections. Eyes were collected on D32 and labeled with an antibody to BAI1 to locate Myo/Nog cells. Hamp;E staining was used to count living cells in the retinal ganglion layer (RGC) and measure the thickness of the nerve fiber layer and inner nuclear layer (NFL:INL).
Results: Endogenous and exogenous Myo/Nog cells increased in glaucomatous eyes around areas of stress, including the cornea, trabecular meshwork, ciliary body and retina. The highest concentration of Myo/Nog cells was present around the RGC layer and cornea. Some Myo/Nog cells had phagocytized microbeads. Glaucomatous eyes treated with Myo/Nog cells displayed a lower concentration of endogenous Myo/Nog cells when compared to PBS and mixed population treatment groups. Addition of Myo/Nog cells also decreased loss of RGC cells and increased NFL:INL thickness in glaucomatous eyes compared to the control groups.
Conclusion: Consistent with other types of ocular injury, Myo/Nog cells accumulate in areas of stress following damage from increased intraocular pressure. Addition of Myo/Nog cells was neuroprotective in the glaucomatous retina.
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Philadelphia College of Osteopathic Medicine
Philadelphia College of Osteopathic Medicineamp;nbsp;
