Development and Characterization of a Photocrosslinkable, Chitosan-Based, Nerve Growth Factor-Eluting Hydrogel for the Ocular Surface.

Purpose: Recombinant human nerve growth factor (rhNGF; cenegermin-bkbj, OXERVATE) is the first and only U.S. Food and Drug Administration-approved treatment for moderate to severe neurotrophic keratopathy. The aim of this study was to determine the feasibility of incorporating a version of rhNGF in a mucoadhesive hydrogel capable of sustained drug release to the ocular surface. Methods: Hydrogels loaded with rhNGF were synthesized by conjugating chitosan with azidobenzoic acid (Az-Ch), adding rhNGF, and exposing the solution to ultraviolet (UV) radiation to induce photocrosslinking. Az-Ch hydrogels were evaluated for physical properties and rhNGF release profiles. Cytocompatbility of Az-Ch was assessed using immortalized human corneal limbal epithelial (HCLE) cells. TF1 erythroleukemic cell proliferation and HCLE cell proliferation and migration were used to assess the bioactivity of rhNGF released from Az-Ch hydrogels. Results: Az-Ch formed hydrogels in <10 seconds of UV exposure and demonstrated high optical transparency (75-85 T%). Az-Ch hydrogels exhibited good cytocompatibility with no demonstratable effect on HCLE cell morphology or viability. rhNGF was released gradually over 24 hours from Az-Ch hydrogels and retained its ability to induce TF1 cell proliferation. No significant difference was observed between rhNGF released from Az-Ch and freshly prepared rhNGF solutions on HCLE cell proliferation or percent wound closure after 12 hours; however, both were significantly better than control (P < 0.01). Conclusions: rhNGF-loaded Az-Ch hydrogels exhibited favorable physical, optical, and drug-release properties, as well as retained drug bioactivity. This drug delivery system has the potential to be further developed for in vivo and translational clinical applications. Translational Relevance: Az-Ch hydrogels may be used to enhance rhNGF therapy in patients with NK.

Reproducible Derivation and Expansion of Corneal Mesenchymal Stromal Cells for Therapeutic Applications.

Purpose: A reproducible protocol for the production of corneal mesenchymal stem/stromal cells (cMSCs) is necessary for potential clinical applications. We aimed to describe successful generation and expansion of cMSCs using an explant method. Methods: Corneoscleral rims of human cadaveric eyes were divided into four pieces and used as explants to allow outgrowth of cMSCs (passage 0, or P0). The cells were subcultured at a 1:10 ratio until passage 5 (P5). The characteristics as well as therapeutic effects of expanded cMSCs were evaluated both in vitro, using a scratch assay, and in vivo using epithelial debridement and chemical injury mouse models. Results: All explants demonstrated outgrowth of cells by 7 days. Although the initial outgrowth included mixed mesenchymal and epithelial cells, by P1 only cMSCs remained. By subculturing each flask at a ratio of 1:10, the potential yield from each cornea was approximately 12 to 16 × 1010 P5 cells. P5 cMSCs demonstrated the cell surface markers of MSCs. The secretome of P5 cMSCs induced faster closure of wounds in an in vitro scratch assay. Subconjunctival injection of P5 cMSCs in mouse models of mechanical corneal epithelial debridement or ethanol injury led to significantly faster wound healing and decreased inflammation, relative to control. Conclusions: cMSCs can be reproducibly derived from human cadaveric corneas using an explant method and expanded with preservation of characteristics and corneal wound healing effects. Translational Relevance: The results of our study showed that cMSCs produced using this scheme can be potentially used for clinical applications.

Therapeutic Effects of Lyophilized Conditioned-Medium Derived from Corneal Mesenchymal Stromal Cells on Corneal Epithelial Wound Healing.

Objectives: The conditioned-medium derived from corneal mesenchymal stromal cells (cMSCs) has been shown to have wound healing and immunomodulatory effects in corneal injury models. Here, the therapeutic effects of lyophilized cMSC conditioned-medium were compared with fresh conditioned-medium. Methods: The epithelial wound healing effects of fresh and lyophilized cMSC conditioned-medium were compared with conditioned-medium from non-MSC cells (corneal epithelial cells) using scratch assay. To evaluate the anti-inflammatory effects of fresh and lyophilized cMSC conditioned-media, macrophages were stimulated by a Toll-Like Receptor (TLR) ligand followed by treatment with the conditioned-media and measuring the expression of inflammatory genes. In vivo wound healing effects of fresh and lyophilized cMSC conditioned-media were assessed in a murine model of cornea epithelial injury. Results: Both fresh and lyophilized cMSCs-derived conditioned-medium induced significantly faster closure of in vitro epithelial wounds compared to conditioned-medium from non-MSC cells (P < .0001). Treating stimulated macrophages with fresh or lyophilized cMSCs-derived conditioned-media significantly decreased the expression of inflammatory genes compared to control (P < .0001). Murine corneal epithelial wounds were healed by 87.6 ± 2.7% and 86.2 ± 4.6% following treatment with fresh and lyophilized cMSC conditioned-media, respectively, while the control was healed by 64.7 ± 16.8% (P < .05). Conclusion: Lyophilized cMSC-derived conditioned-medium is as effective as fresh conditioned-medium in promoting wound healing and modulating inflammation. The results of this study support the application of lyophilized cMSCs-derived conditioned-medium, which allows for more extended storage, as a promising non-invasive option in the treatment of corneal wounds.

Glaucoma Care of Prison Inmates at an Academic Hospital.

Importance: Glaucoma care for prison inmates is underrepresented in the literature even though managing the treatment of such patients may provide unique challenges. Objectives: To evaluate the glaucoma profile of prison inmates treated at an academic ophthalmology center and to report on the medical and surgical management and follow-up metrics. Design, Setting, and Participants: This retrospective cohort study assessed data from 82 incarcerated patients treated at the glaucoma clinic, an academic referral center at the University of Illinois at Chicago, between January 2013 and December 2017. Main Outcomes and Measures: Diagnosis, glaucoma severity, medical and surgical interventions, and patient-reported medication adherence were recorded for each visit. Recommended and actual follow-up times were recorded and compared. Data analyses were conducted from January 2013 to December 2018. Results: In total, 82 patients (161 eyes) had 375 visits during the study period. All patients were male and ranged from 20 to 75 years of age (mean [SD] age, 50.8 [11.9] years). Most participants were black patients (65 [79.3%]). The most common diagnoses were primary open-angle glaucoma (POAG; 53 eyes [32.9%]) and POAG suspect (52 eyes [32.3%]). Glaucoma severity ranged from mild (25 of 77 eyes [32.5%]) to advanced (41 of 77 eyes [53.2%]). Overall, 59 patients (73.2%) were treated medically with up to 4 topical agents (40.0%). Of those treated, 70.0% of patients (95% CI, 57.7%-81.2%) reported medication nonadherence during at least 1 visit. Medication nonadherence was more common among those taking 4 different topical medications (21 of 24 [87.5%]) compared with others taking fewer medications (20 of 35 [57.1%]), for a difference of 30.4% (95% CI, 7.0%-53.6%; P = .02), and among those with advanced disease (22 of 26 [84.6%]) compared with glaucoma suspect (6 of 13 [46.2%]), for a difference of 38.4% (95% CI, 9.3%-67.5%; P = .02). Nineteen office procedures, including laser peripheral iridotomy and laser trabeculoplasty, were performed on 14 eyes. Seventeen incisional glaucoma procedures were performed on 15 eyes, including glaucoma drainage device implant (11 procedures [64.7%]) and trabeculectomy (3 procedures [17.6%]). Only 26.6% of return office visits (95% CI, 21.3%-32.3%) occurred within the recommended follow-up time frame. Furthermore, 93 patients (34.8%; 95% CI, 28.2%-40.0%) were seen more than 1 month after the recommended follow-up. Conclusions and Relevance: Despite incarceration in prison, where medication administration and appointment attendance are theoretically controlled, the results of this study suggested that substantial medication and follow-up nonadherence exists among inmates.

Characterization of an Electronic Corneal Prosthesis System.

PURPOSE: Corneal opacity is a leading cause of reversible blindness worldwide. An electronic corneal prosthesis, or intraocular projector, could potentially restore high-quality vision without need for corneal clarity. MATERIALS AND METHODS: Four intraocular projection systems were constructed from commercially available electronic components and encased in biocompatible plastic housing. They were tested for optical properties, biocompatibility, heat dissipation, waterproofing, and accelerated wear. A surgical implantation technique was developed. RESULTS: Intraocular projectors were produced of a size that can fit within the eye. Their optics produce better than 20/200 equivalent visual acuity. MTT assay demonstrated no cytotoxicity of devices in vitro. Temperature testing demonstrated less than 2°C increase in temperature after 1 h. Three devices lasted over 12 weeks under accelerated wear conditions. Implantation surgery was demonstrated via corneal trephination insertion in a cadaver eye. CONCLUSION: This is the first study to demonstrate and characterize fully functional intraocular projection systems. This technology has the potential to be an important new tool in the treatment of intractable corneal blindness.

Self-insertion of foreign bodies into the orbit and periocular tissue.

We describe six patients with 12 separate episodes of self-inflicted periocular foreign body injuries, which presented to our institution recently. All patients were male, relatively young (mean 28.5 years old), incarcerated, and had significant underlying psychiatric conditions. The subjects had inserted staples (6), paperclips (2), or other small metallic wire segments (4) into the periocular region. Most cases (9/12) involved concurrent self-inflicted injury to other body parts. Ten cases involved foreign bodies inserted through the palpebral conjunctiva into the upper eyelid, while two cases involved insertion into the orbit. Identification and surgical retrieval of foreign bodies was successful in most cases (9/11) but was not attempted in one case. Self-inflicted periocular injuries, while rare, are challenging cases for which the ophthalmologist should be prepared. A multidisciplinary approach, including psychiatric assessment and treatment, is important for optimal care.

Retinal Pre-Conditioning by CD59a Knockout Protects against Light-Induced Photoreceptor Degeneration.

Complement dysregulation plays a key role in the pathogenesis of age-related macular degeneration (AMD), but the specific mechanisms are incompletely understood. Complement also potentiates retinal degeneration in the murine light damage model. To test the retinal function of CD59a, a complement inhibitor, CD59a knockout (KO) mice were used for light damage (LD) experiments. Retinal degeneration and function were compared in WT versus KO mice following light damage. Gene expression changes, endoplasmic reticulum (ER) stress, and glial cell activation were also compared. At baseline, the ERG responses and rhodopsin levels were lower in CD59aKO compared to wild-type (WT) mice. Following LD, the ERG responses were better preserved in CD59aKO compared to WT mice. Correspondingly, the number of photoreceptors was higher in CD59aKO retinas than WT controls after LD. Under normal light conditions, CD59aKO mice had higher levels than WT for GFAP immunostaining in Müller cells, mRNA and protein levels of two ER-stress markers, and neurotrophic factors. The reduction in photon capture, together with the neurotrophic factor upregulation, may explain the structural and functional protection against LD in the CD59aKO.

AMD-like retinopathy associated with intravenous iron.

Iron accumulation in the retina is associated with the development of age-related macular degeneration (AMD). IV iron is a common method to treat iron deficiency anemia in adults, and its retinal manifestations have not hitherto been identified. To assess whether IV iron formulations can be retina-toxic, we generated a mouse model for iron-induced retinal damage. Male C57BL/6J mice were randomized into groups receiving IV iron-sucrose (+Fe) or 30% sucrose (-Fe). Iron levels in neurosensory retina (NSR), retinal pigment epithelium (RPE), and choroid were assessed using immunofluorescence, quantitative PCR, and the Perls' iron stain. Iron levels were most increased in the RPE and choroid while levels in the NSR did not differ significantly in +Fe mice compared to controls. Eyes from +Fe mice shared histological features with AMD, including Bruch's membrane (BrM) thickening with complement C3 deposition, as well as RPE hypertrophy and vacuolization. This focal degeneration correlated with areas of high choroidal iron levels. Ultrastructural analysis provided further detail of the RPE/photoreceptor outer segment vacuolization and Bruch's membrane thickening. Findings were correlated with a clinical case of a 43-year-old patient who developed numerous retinal drusen, the hallmark of AMD, within 11 months of IV iron therapy. Our results suggest that IV iron therapy may have the potential to induce or exacerbate a form of retinal degeneration. This retinal degeneration shares features with AMD, indicating the need for further study of AMD risk in patients receiving IV iron treatment.