Neuroprotective Effects of Amnion-derived Cellular Cytokine Solution (ACCS) in Experimental Optic Neuritis

Program Number: 5528 Poster Board Number: B0099 Presentation Time: 8:30 AM–10:15 AM Neuroprotective Effects of Amnion-derived Cellular Cytokine Solution (ACCS) in Experimental Optic Neuritis Reas Sulaimankutty1, Kimberly Dine1, Helayna Brown1, Larry R. Brown2, Kenneth S. Shindler1. 1Ophthalmology, Univ of Pennsylvania, Scheie Eye Inst, Philadelphia, PA; 2Stemnion Inc, Pittsburgh, PA. Purpose: Optic neuritis is a demyelinating inflammation of the optic nerve that often occurs in multiple sclerosis (MS) patients. Loss of retinal ganglion cells (RGCs) and their axons also occurs in optic neuritis, and correlates with permanent vision loss. ACCS is a novel biologic mixture of growth factors and cytokines secreted from Amnion-derived Multipotent Progenitor (AMP) cells, that exhibits anti-inflammatory and neuroprotective properties in a variety of disease models. The ability of ACCS to suppress optic neuritis in the experimental autoimmune encephalomyelitis (EAE) model of MS was examined. Methods: EAE was induced in C57/BL6 mice by immunization with myelin oligodendroglial glycoprotein peptide. Mice were treated daily with one drop (6 uL) of ACCS intranasally beginning before or after onset of optic neuritis. Visual function was assessed by optokinetic responses (OKR) at baseline, then weekly until sacrifice 6 weeks post-immunization. Retinas and optic nerves were isolated. RGCs were immunolabeled with Brn3a antibodies to quantify RGC survival. Inflammation was assessed by H&E and Iba1 (macrophage/ microglia marker) staining, demyelination by luxol fast blue staining, and axonal loss by neurofilament staining of optic nerve sections. Results: Progressive decreases in OKR occurred in vehicle-treated EAE mice, along with significant RGC loss, consistent with prior studies showing onset of optic neuritis occurring 12-15 days after EAE induction. Daily intranasal ACCS treatment beginning on day 0 (day of immunization), 15, 22, or 30, significantly reduced the level of vision loss, and treatment from day 0 or day 15 significantly attenuated RGC loss. ACCS also decreased the degree of demyelination and axonal loss, but had limited effects on the level of inflammation in the optic nerve. Conclusions: ACCS treatment attenuates RGC loss, preserves OKR responses, and reduces demyelination and axonal loss during experimental optic neuritis in EAE mice. ACCS exerts effects with treatment initiated before and after onset of optic neuritis, suggesting it may be useful as a preventative or abortive therapy. Results suggest ACCS is a potential treatment for optic neuritis that warrants further study. Furthermore, potent effects seen after intranasal administration suggest this may be a novel drug delivery method for optic neuritis. Commercial Relationships: Reas Sulaimankutty, None; Kimberly Dine, None; Helayna Brown, None; Larry R. Brown, Stemnion Inc (I); Kenneth S. Shindler, Stemnion Inc (F) Support: NIH Grant EY019014 Program Number: 5529 Poster Board Number: B0100 Presentation Time: 8:30 AM–10:15 AM Experimental optic neuritis induced by the microinjection of lipopolysaccharide into the optic nerve Marcos Luis Aranda, Damian Dorfman, Pablo Sande, Ruth E. Rosenstein. Human Biochemistry, University of Buenos Aires /Sch of Medicine, Buenos Aires, Argentina. Purpose: Optic neuritis (ON) is a condition involving primary inflammation, demyelination, and axonal injury in the optic nerve which leads to retinal ganglion cell (RGC) loss, and visual dysfunction. We investigated the ability of a single microinjection of bacterial lipopolysaccharide (LPS) directly into the optic nerve to induce functional and structural alterations compatible with ON. For this purpose, optic nerves from male Wistar rats remained intact or were injected with vehicle or LPS. Methods: The effect of LPS was evaluated at several time points post-injection in terms of: i) visual pathway and retinal function (visual evoked potentials (VEPs) and electroretinograms, (ERGs), respectively), ii) anterograde transport from the retina to its projection areas, iii) consensual pupil light reflex (PLR), iv) optic nerve histology, v) microglia/macrophage reactivity (by Iba1and ED1-immunostaining), vi) astrocyte reactivity (by glial fibrillary acid protein-immunostaining), vii) axon number (by toluidine blue staining), vii) demyelination (by myelin basic protein immunoreactivity and luxol fast blue staining), viii) optic nerve ultrastructure, and ix) RGC number (by Brn3a immunoreactivity). Results: LPS induced a significant and persistent decrease in VEP amplitude and PLR,without changes in the ERG. In addition, LPS induced a deficit in anterograde transport, and an early inflammatory response consisting in an increased cellularity, and Iba-1 and ED1immunoreactivity in the optic nerve, which were followed by changes in axonal density, astrocytosis, demyelination, and axon and RGC loss. Conclusions: These results suggest that the microinjection of LPS into the optic nerve may serve as a new experimental model of primary ON. Commercial Relationships: Marcos Luis Aranda, None; Damian Dorfman, None; Pablo Sande, None; Ruth E. Rosenstein, None Support: CONICET-PIP0446, ANPCyT-PICT0610, FUNDACION FLORENCIO FIORINI, UBA