All

Sharif R, Khaled ML, McKay TB, Liu Y, Karamichos D. Transcriptional profiling of corneal stromal cells derived from patients with keratoconus. Sci Rep 2019;9(1):12567.Abstract
Keratoconus (KC) is a multi-factorial corneal ectasia with unknown etiology affecting approximately 1:2000 people worldwide. Dysregulated gene expression, using RNA-Seq technology, have been reported in KC corneal tissue. However, the differential expression of genes, in KC corneal stromal cells have been widely ignored. We utilized mRNA-Seq to analyze gene expression in primary human corneal stromal cells derived from five non-Keratoconus healthy (HCF) and four Keratoconus (HKC) donors. Selected genes were further validated using real time PCR (RT-PCR). We have identified 423 differentially expressed genes with 187 down- and 236 up-regulated in KC-affected corneal stromal cells. Gene ontology analysis using WebGestalt indicates the enrichment of genes involved in cell migration, extracellular matrix, adherens junction, and MAPK signaling. Our protein-protein interaction network analysis identified several network seeds, such as EGFR, NEDD4, SNTA1, LGALS3BP, HSPB1, SDC2, MME, and HIF1A. Our work provides an otherwise unknown information on the transcriptional changes in HKCs, and reveals critical mechanisms of the cellular compartment. It also highlights the importance of human-based in vitro studies on a disease that currently lacks strong biomarkers and animal models.
Handa JT, Bowes Rickman C, Dick AD, Gorin MB, Miller JW, Toth CA, Ueffing M, Zarbin M, Farrer LA. A systems biology approach towards understanding and treating non-neovascular age-related macular degeneration. Nat Commun 2019;10(1):3347.Abstract
Age-related macular degeneration (AMD) is the most common cause of blindness among the elderly in the developed world. While treatment is effective for the neovascular or "wet" form of AMD, no therapy is successful for the non-neovascular or "dry" form. Here we discuss the current knowledge on dry AMD pathobiology and propose future research directions that would expedite the development of new treatments. In our view, these should emphasize system biology approaches that integrate omic, pharmacological, and clinical data into mathematical models that can predict disease onset and progression, identify biomarkers, establish disease causing mechanisms, and monitor response to therapy.
Bulka CM, Dammann O, Santos HP, VanderVeen DK, Smeester L, Fichorova R, O'Shea MT, Fry RC. Placental CpG Methylation of Inflammation, Angiogenic, and Neurotrophic Genes and Retinopathy of Prematurity. Invest Ophthalmol Vis Sci 2019;60(8):2888-2894.Abstract
Purpose: Extremely preterm infants are at increased risk for retinopathy of prematurity (ROP). We previously identified several inflammatory proteins that were expressed early in life and are associated with an increased risk of ROP and several angiogenic and neurotrophic growth factors in the neonatal systemic circulation that are associated with a lower risk of ROP. In this paper, we report the results of a set of analyses designed to test the hypothesis that placental CpG methylation levels of 12 inflammation-, angiogenic-, and neurotrophic-associated genes predict the occurrence of prethreshold ROP in extremely preterm newborns. Methods: We used placental CpG methylation data from 395 newborns from the Extremely Low Gestational Age Newborns study. Results: Multivariable regression models revealed that placental DNA methylation of 16 CpG sites representing 8 genes were associated with prethreshold ROP. Specifically, CpG methylation in the serum amyloid A SAA1 and SAA2, brain-derived neurotrophic factor (BDNF), myeloperoxidase (MPO), C-reactive protein (CRP), angiopoietin 1 (ANGPT1), and tumor necrosis factor receptor superfamily member 1B (TNFRSF1B) genes was associated with a lower risk of prethreshold ROP. Conversely, CpG methylation at three probes within tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) and in two alternative probes within the BDNF and ANGPT1 genes was associated with an increased risk of ROP. Conclusions: CpG methylation may be a useful marker for improving ROP prediction, opening the opportunity for early intervention to lessen disease severity.
Sauvage F, Fraire JC, Remaut K, Sebag J, Peynshaert K, Harrington M, Van de Velde FJ, Xiong R, Tassignon M-J, Brans T, Braeckmans K, De Smedt SC. Photoablation of Human Vitreous Opacities by Light-Induced Vapor Nanobubbles. ACS Nano 2019;13(7):8401-8416.Abstract
Myopia, diabetes, and aging are the main causes of progressive vitreous collagen aggregation, resulting in vitreous opacities, which can significantly disturb vision. As vitreous opacities, which induce the visual phenomenon of "floaters", are accessible with nanomaterials and light, we propose a nanotechnology-based approach to locally ablate them with highly reduced light energy compared to the more traditional YAG laser therapy. Our strategy relies on the plasmon properties of gold nanoparticles that generate vapor nanobubbles upon pulsed-laser illumination whose mechanical force can ablate vitreous opacities. We designed gold nanoparticles coated with hyaluronic acid (HA), which have excellent diffusional mobility in human vitreous, an essential requirement to reach the vitreous opacities. In addition, we found that HA-coated gold nanoparticles can accumulate extensively on human vitreous opacities that were obtained by vitrectomy from patients with vision-degrading myodesopsia. When subsequently applying nanosecond laser pulses, the collagen aggregates were efficiently destroyed with ∼1000 times less light energy than typically used in YAG laser therapy. This low-energy "floater-specific destruction", which is due to the accumulation of the small gold nanoparticles on the opacities, is attractive, as it may be safer to the surrounding ocular tissues while at the same time being easier and faster to apply compared to YAG laser therapy, where the opacities need to be ablated piece by piece by a tightly focused laser beam. Gold nanoparticle-assisted photoablation may therefore provide a safer, faster, and more reliable destruction of vitreous opacities in the treatment of ophthalmologic diseases.
Chen N, Hu Z, Yang Y, Han H, Lei H. Inactive Cas9 blocks vitreous-induced expression of Mdm2 and proliferation and survival of retinal pigment epithelial cells. Exp Eye Res 2019;186:107716.Abstract
Mouse double minute (MDM)2 single nucleotide polymorphism (SNP) 309G allele in the second promoter of MDM2 enhances vitreous-induced expression of Mdm2 and degradation of the tumor suppressor protein p53. This MDM2 contributes to certain cancer development and experimental proliferative vitreoretinopathy. The goal of this study is to discover a novel strategy to only block vitreous-induced expression of Mdm2 for preventing vitreous-induced cell proliferation and survival and thus find a potential novel strategy to treat proliferation-related diseases. We created two mutations (D10A and H840A) in Streptococcus pyogenes (Sp)Cas9 within the nuclease domains (RuvC1 and HNH, respectively) to render this SpCas9 nuclease dead named as dCas9 in a lentiCRISPR v2 vector. Then an MDM2-sgRNA targeting the second promoter of human MDM2 gene was cloned into this vector for producing lentivirus to infect human retinal pigment epithelial (RPE) cells with, which carry a heterozygous genotype of MDM2. lacZ-sgRNA was used as a control. As a result, we discovered that vitreous from experimental rabbits induced a 1.9 ± 0.2 fold increase in Mdm2 and a 2.0 ± 0.2 fold decrease in p53 in the RPE cells with dCas9/lacZ-sgRNA compared to those with dCas9/MDM2-sgRNA, suggesting that dCas9 under the guidance of the MDM2-sgRNA prevented RV-stimulated increase in Mdm2. In addition, we found that the rabbit vitreous significantly enhanced cell proliferation (1.5 ± 0.2 fold), survival against apoptosis (2.2 ± 0.2 fold), migration (10 ± 1.5%) and contraction (112.7 ± 14.1 mm) of the cells with dCas9/lacZ-sgRNA compared with those with dCas9/MDM2-sgRNA. These results indicated that application of the dCas9 targeted to the P2 of MDM2 is a potential therapeutic approach to diseases due to the P2-driven aberrant expression of Mdm2 - such as proliferative vitreoretinopathy.
Gaca AO, Lemos JA. Adaptation to Adversity: the Intermingling of Stress Tolerance and Pathogenesis in Enterococci. Microbiol Mol Biol Rev 2019;83(3)Abstract
SUMMARY is a diverse and rugged genus colonizing the gastrointestinal tract of humans and numerous hosts across the animal kingdom. Enterococci are also a leading cause of multidrug-resistant hospital-acquired infections. In each of these settings, enterococci must contend with changing biophysical landscapes and innate immune responses in order to successfully colonize and transit between hosts. Therefore, it appears that the intrinsic durability that evolved to make enterococci optimally competitive in the host gastrointestinal tract also ideally positioned them to persist in hospitals, despite disinfection protocols, and acquire new antibiotic resistances from other microbes. Here, we discuss the molecular mechanisms and regulation employed by enterococci to tolerate diverse stressors and highlight the role of stress tolerance in the biology of this medically relevant genus.
Kheirkhah A, Coco G, Satitpitakul V, Pham TT, Dana R. Limbal and Conjunctival Epithelial Thickness in Ocular Graft-Versus-Host Disease. Cornea 2019;38(10):1286-1290.Abstract
PURPOSE: To compare the thickness of the limbal epithelium (LE) and the bulbar conjunctival epithelium (BCE) between patients with dry eye disease (DED) with and without ocular graft-versus-host disease (GVHD). METHODS: This cross-sectional study enrolled 40 patients with moderate to severe DED including 20 with and 20 without chronic ocular GVHD. All patients had a comprehensive clinical ophthalmic assessment. Moreover, the thickness of the LE and BCE in both nasal and temporal regions of both eyes was measured using spectral domain optical coherence tomography. RESULTS: The average LE thickness in all patients with dry eye (GVHD and non-GVHD) was 65.8 ± 11.9 μm temporally and 69.7 ± 11.1 μm nasally (P = 0.02). The average BCE thickness was 55.8 ± 11.4 μm temporally and 60.1 ± 11.0 μm nasally (P = 0.03). There were no statistically significant differences between GVHD and non-GVHD groups in LE thickness (69.6 ± 11.7 vs. 66.1 ± 6.2 μm, respectively, P = 0.31) or BCE thickness (58.9 ± 9.6 vs. 57.3 ± 9.8 μm, respectively, P = 0.82). There was a significant correlation between LE thickness and BCE thickness (P = 0.01, Rs = 0.41). A statistically significant negative correlation was also observed between LE thickness and age (P = 0.002, Rs = -0.35). There were no significant correlations between the thickness of the LE or BCE and other clinical parameters. CONCLUSIONS: No difference exists in the thickness of the ocular surface epithelia between dry eyes with and without ocular GVHD, which would suggest that these epithelial changes may be independent of the underlying etiology and possibly only reflect the disease severity. Furthermore, there are regional variations in the thickness of the ocular surface epithelia in patients with DED.
Gangaputra SS, Newcomb CW, Joffe MM, Dreger K, Begum H, Artornsombudh P, Pujari SS, Daniel E, Sen NH, Suhler EB, Thorne JE, Bhatt NP, Foster SC, Jabs DA, Nussenblatt RB, Rosenbaum JT, Levy-Clarke GA, Kempen JH, Kempen JH. Comparison Between Methotrexate and Mycophenolate Mofetil Monotherapy for the Control of Noninfectious Ocular Inflammatory Diseases. Am J Ophthalmol 2019;208:68-75.Abstract
PURPOSE: To compare mycophenolate mofetil (MMF) to methotrexate (MTX) as corticosteroid-sparing therapy for ocular inflammatory diseases. DESIGN: Retrospective analysis of cohort study data. METHODS: Participants were identified from the Systemic Immunosuppressive Therapy for Eye Diseases Cohort Study. Demographic and clinical characteristics were obtained via medical record review. The study included 352 patients who were taking single-agent immunosuppression with MTX or MMF at 4 tertiary uveitis clinics. Marginal structural models (MSM)-derived statistical weighting created a virtual population with covariates and censoring patterns balanced across alternative treatments. With this methodological approach, the results estimate what would have happened had none of the patients stopped their treatment. Survival analysis with stabilized MSM-derived weights simulated a clinical trial comparing MMF vs MTX for noninfectious inflammatory eye disorders. The primary outcome was complete control of inflammation on prednisone ≤10 mg/day, sustained for ≥30 days. RESULTS: The time to success was shorter (more favorable) for MMF than MTX (hazard ratio = 0.68, 95% confidence interval: 0.46-0.99). Adjusting for covariates, the proportion achieving success was higher at every point in time for MMF than MTX from 2 to 8 months, then converges at 9 months. The onset of corticosteroid-sparing success took more than 3 months for most patients in both groups. Outcomes of treatment (MMF vs MTX) were similar across all anatomic sites of inflammation. The incidence of stopping therapy for toxicity was similar in both groups. CONCLUSIONS: Our results suggest that, on average, MMF may be faster than MTX in achieving corticosteroid-sparing success in ocular inflammatory diseases.
El Rassi E, Adappa ND, Battaglia P, Castelnuovo P, Dallan I, Freitag SK, Gardner PA, Lenzi R, Lubbe D, Metson R, Moe KS, Muscatello L, Mustak H, Nogueira JF, Palmer JN, Prepageran N, Ramakirshnan VR, Sacks R, Snyderman CH, Stefko TS, Turri-Zanoni M, Wang EW, Zhou B, Bleier BS. Development of the international orbital Cavernous Hemangioma Exclusively Endonasal Resection (CHEER) staging system. Int Forum Allergy Rhinol 2019;9(7):804-812.Abstract
BACKGROUND: Orbital cavernous hemangiomas (OCH) are the most common adult orbital tumor and represent an ideal index lesion for endonasal orbital tumor surgery. In order to standardize outcomes reporting, an anatomic-based staging system was developed. METHODS: An international, multidisciplinary panel of 23 experts in orbital tumor surgery was formed. A modified Delphi method was used to develop the cavernous hemangioma exclusively endonasal resection (CHEER) staging system with a total of 2 rounds being completed. RESULTS: Tumors medial to a plane along the long axis of the optic nerve may be considered amenable for an exclusively endonasal resection. In select cases, tumors may extend inferolaterally if the tumor remains below a plane from the contralateral naris through the long axis of the optic nerve (ie, plane of resectability [POR]). This definition reached consensus with 91.3% of panelists in agreement. Five stages were designed based on increasing technical resection difficulty and potential for morbidity. Stages were based on the relationship of the tumor to the extraocular muscles, the inferomedial muscular trunk of the ophthalmic artery (IMT), and orbital foramina. Staging by anatomic location also reached consensus with 87.0% of panelists in agreement. Size was not included in the staging system due to the lack of agreement on the contribution of size to resection difficulty. CONCLUSION: Endoscopic orbital tumor surgery is a nascent field with a growing, yet heterogeneous, body of literature. The CHEER staging system is designed to facilitate international, high-quality, standardized studies establishing the safety, efficacy, and outcomes of endonasal resection of OCH.
Laíns I, Chung W, Kelly RS, Gil J, Marques M, Barreto P, Murta JN, Kim IK, Vavvas DG, Miller JB, Silva R, Lasky-Su J, Liang L, Miller JW, Husain D. Human Plasma Metabolomics in Age-Related Macular Degeneration: Meta-Analysis of Two Cohorts. Metabolites 2019;9(7)Abstract
The pathogenesis of age-related macular degeneration (AMD), a leading cause of blindness worldwide, remains only partially understood. This has led to the current lack of accessible and reliable biofluid biomarkers for diagnosis and prognosis, and absence of treatments for dry AMD. This study aimed to assess the plasma metabolomic profiles of AMD and its severity stages with the ultimate goal of contributing to addressing these needs. We recruited two cohorts: Boston, United States ( = 196) and Coimbra, Portugal ( = 295). Fasting blood samples were analyzed using ultra-high performance liquid chromatography mass spectrometry. For each cohort, we compared plasma metabolites of AMD patients versus controls (logistic regression), and across disease stages (permutation-based cumulative logistic regression considering both eyes). Meta-analyses were then used to combine results from the two cohorts. Our results revealed that 28 metabolites differed significantly between AMD patients versus controls (false discovery rate (FDR) -value: 4.1 × 10-1.8 × 10), and 67 across disease stages (FDR -value: 4.5 × 10-1.7 × 10). Pathway analysis showed significant enrichment of glycerophospholipid, purine, taurine and hypotaurine, and nitrogen metabolism (-value ≤ 0.04). In conclusion, our findings support that AMD patients present distinct plasma metabolomic profiles, which vary with disease severity. This work contributes to the understanding of AMD pathophysiology, and can be the basis of future biomarkers and precision medicine for this blinding condition.
Shanbhag SS, Rashad R, Chodosh J, Saeed HN. Long-Term Effect of a Treatment Protocol for Acute Ocular Involvement in Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis. Am J Ophthalmol 2019;208:331-341.Abstract
PURPOSE: To describe the long-term effect of a treatment protocol for ocular involvement in acute Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), including focused ocular examination and pathology-appropriate use of lubrication, topical corticosteroids, topical antibiotics, and amniotic membrane transplantation (AMT). DESIGN: Retrospective, comparative case series. METHODS: A total of 48 patients (96 eyes) were included in this study. Nine of 48 patients (18 eyes) had acute SJS/TEN from 2000 to 2007 and did not receive protocol care (Group I). Thirty-nine of 48 patients (78 eyes) had acute SJS/TEN from 2008 to 2017 and received protocol care (Group II). The main outcome measures were best-corrected visual acuity (BCVA) at final follow-up visit and incidence of complications in the chronic phase. RESULTS: No eyes in Group I received AMT for SJS/TEN, compared to 87% of qualifying eyes in Group II (P < .0001) There was a significant difference in the proportion of eyes with BCVA ≥20/40 at last follow-up between Group I and Group II (33% vs 92%, P < .001). The proportion of eyes with vision-threatening complications in the chronic phase was significantly higher in Group I versus Group II (67% vs 17%, P = .002), with most complications occurring in the first 2 years after disease onset in both groups. CONCLUSIONS: A specific protocol for acute ocular care in SJS/TEN, including aggressive use of AMT, was highly successful in reducing corneal blindness and severe vision-threatening complications of the disorder.
Dorr M, Kwon MY, Lesmes LA, Miller A, Kazlas M, Chan K, Hunter DG, Lu Z-L, Bex PJ. Binocular Summation and Suppression of Contrast Sensitivity in Strabismus, Fusion and Amblyopia. Front Hum Neurosci 2019;13:234.Abstract
: Amblyopia and strabismus affect 2%-5% of the population and cause a broad range of visual deficits. The response to treatment is generally assessed using visual acuity, which is an insensitive measure of visual function and may, therefore, underestimate binocular vision gains in these patients. On the other hand, the contrast sensitivity function (CSF) generally takes longer to assess than visual acuity, but it is better correlated with improvement in a range of visual tasks and, notably, with improvements in binocular vision. The present study aims to assess monocular and binocular CSFs in amblyopia and strabismus patients. : Both monocular CSFs and the binocular CSF were assessed for subjects with amblyopia ( = 11), strabismus without amblyopia ( = 20), and normally sighted controls ( = 24) using a tablet-based implementation of the quick CSF, which can assess a full CSF in <3 min. Binocular summation was evaluated against a baseline model of simple probability summation. : The CSF of amblyopic eyes was impaired at mid-to-high spatial frequencies compared to fellow eyes, strabismic eyes without amblyopia, and control eyes. Binocular contrast summation exceeded probability summation in controls, but not in subjects with amblyopia (with or without strabismus) or strabismus without amblyopia who were able to fuse at the test distance. Binocular summation was less than probability summation in strabismic subjects who were unable to fuse. : We conclude that monocular and binocular contrast sensitivity deficits define important characteristics of amblyopia and strabismus that are not captured by visual acuity alone and can be measured efficiently using the quick CSF.

Pages