Activated Omental Stromal Cells Protect Against Light-Induced Retinal Injury 24 th Annual Loyola Ophthalmology Resident-Alumni/Mission Day Evan Price, M.D., Ping Bu, M.D., Periannan Sethupathi, Ph.D., Evan Stubbs, Ph.D., Jay Perlman, M.D., Ph.D. June 14, 2013

The authors have no financial disclosures to report

Objectives To review the state of stem cell research as it pertains to ophthalmic disease To understand the findings of the current study To discuss the implications of the research performed and possible future areas of study

Background Retinal diseases comprise a large share of the visual morbidity in the world (1-3) There is a great need for treatments of retinal disease that will restore vision that has already been lost E.g., nonexudative macular degeneration (4)

Background Stem cell therapies may provide the solutions these patients have been waiting for (5-7) –Limbal stem cell deficiency –Glaucoma –Retinal vascular disease –Degenerative retinal disease Sources of stem cells for retinal applications –Embryonic stem cells (ESCs) –Induced pluripotent stem cells (iPSCs) –Endothelial progenitor cells (EPCs) from umbilical cord blood or bone marrow –Omental stromal cells (OSCs)

Background The regenerative and immunosuppressive properties of activated omentum are an area of active research (8-11) –Spinal cord –Pancreas –Kidney –Skin –Lungs

Our Research Experimental animal study looking at the effect of activated OSCs on light-damaged mouse retinas –Morphology –Function (ERG) Male BALB/c albino mice were divided into 2 groups (n=4 for each group) –OSC-treated group –Vehicle-treated group (control)

Electroretinography Performed prior to and six days after light exposure –Dark adapted overnight –Wire loop electrode in contact with the cornea (12) –Single-flash stimulus Light injury (13) –12 hours dark adaptation –Eyes dilated –6000 lux of white light for 4 hours Photo by Evan Price

Methods Isolation of OSCs from activated mouse omentum –Male BALB/c albino mice –Intraperitoneal injection of a polydextran particle slurry –Omenta harvested –Collagenase I digestion Intraperitoneal injection Outcomes –Six days after light exposure –ERGs performed –Retinas examined histologically

Results

Vehicle Pre Post

Results/Conclusions Vehicle Pre Post VehiclePre: ± 27.9 μV Post: 74.2 ± 9.3 μV OSCPre: ± 6.6 μV Post: ± 16.4 μV VehiclePre: ± 54.5 μV Post: ± 37.3 μV OSCPre: ± 62.6 μV Post: ± 44.6 μV

Limitations/Future Directions Sample size Amount of light exposure Route of injection

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