July 2020

Ibrahim AS, Hussein K, Wang F, Wan M, Saad N, Essa M, Kim I, Shakoor A, Owen LA, Deangelis MM, Al-Shabrawey M. Bone Morphogenetic Protein (BMP)4 But Not BMP2 Disrupts the Barrier Integrity of Retinal Pigment Epithelia and Induces Their Migration: A Potential Role in Neovascular Age-Related Macular Degeneration. J Clin Med 2020;9(7)Abstract
Disruption of retinal pigment epithelial (RPE) barrier integrity and RPE migration are hallmark features in neovascular age-related macular degeneration (nAMD), but the underlying causes and pathophysiology are not completely well-defined. Herein, we aimed to evaluate the effect of bone morphogenetic proteins (BMPs) on the barrier function and migration of RPE. In particular, we investigated the role of BMP2 and BMP4 in these processes as our analysis of RNA-sequencing (seq) data from human donor eyes demonstrated that they are highly differentially expressed BMP members in macular RPE/choroid versus macular retina. We used electrical cell-substrate impedance sensing (ECIS) system to monitor precisely in real time the barrier integrity and migration of ARPE-19 after treatment with various concentrations of BMP2 or BMP4. Immunofluorescence was also used to assess the changes in the expression and the organization of the key tight junction protein, zona occludens (ZO)-1, in ARPE-19 cells under BMP2 or BMP4 treatment. This was followed by measuring the activity of matrix metalloproteinases (MMPs). Finally, RNA-seq and ELISA were used to determine the local and circulating levels of BMP2 and BMP4 in retinas and serum samples from nAMD donors. Our ECIS results showed that BMP4 but not BMP2 decreased the transcellular electrical resistance (TER) of ARPE-19 and increased their migration in comparison with control (vehicle-treated cells). Furthermore, immunofluorescence showed a disorganization of ZO-1 in BMP4-treated ARPE-19 not in BMP2-treated cells or vehicle-treated controls. This effect of BMP4 was associated with significant increases in the activity of MMPs, specifically MMP2. Lastly, these results were corroborated by additional findings that circulating but not local BMP4 levels were significantly higher in nAMD donor samples compared to controls. Collectively, our results demonstrated unreported effects of BMP4 on inducing RPE dysfunction and suggest that BMP4 but not BMP2 may represent a potential therapeutic target in nAMD.
Haque M, Lei F, Xiong X, Ren Y, Kumar A, Das JK, Ren X, Fang D, de Figueiredo P, Yang J-M, Song J. Stem Cell-Derived Viral Antigen-Specific T Cells Suppress HBV Replication through Production of IFN-γ and TNF-⍺. iScience 2020;23(7):101333.Abstract
The viral antigen (Ag)-specific CD8 cytotoxic T lymphocytes (CTLs) derived from pluripotent stem cells (PSCs), i.e., PSC-CTLs, have the ability to suppress hepatitis B virus (HBV) infection. After adoptive transfer, PSC-CTLs can infiltrate into the liver to suppress HBV replication. Nevertheless, the mechanisms by which the viral Ag-specific PSC-CTLs provoke the antiviral response remain to be fully elucidated. In this study, we generated the functional HBV surface Ag-specific CTLs from the induced PSC (iPSCs), i.e., iPSC-CTLs, and investigated the underlying mechanisms of the CTL-mediated antiviral replication in a murine model. We show that adoptive transfer of HBV surface Ag-specific iPSC-CTLs greatly suppressed HBV replication and prevented HBV surface Ag expression. We further demonstrate that the adoptive transfer significantly increased T cell accumulation and production of antiviral cytokines. These results indicate that stem cell-derived viral Ag-specific CTLs can robustly accumulate in the liver and suppress HBV replication through producing antiviral cytokines.
Hellström A, Hellström W, Hellgren G, Smith LEH, Puttonen H, Fyhr I-M, Sävman K, Nilsson AK, Klevebro S. Docosahexaenoic Acid and Arachidonic Acid Levels Are Associated with Early Systemic Inflammation in Extremely Preterm Infants. Nutrients 2020;12(7)Abstract
Fetal and early postnatal inflammation have been associated with increased morbidity in extremely preterm infants. This study aimed to demonstrate if postpartum levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) were associated with early inflammation. In a cohort of 90 extremely preterm infants, DHA and AA in cord blood, on the first postnatal day and on postnatal day 7 were examined in relation to early systemic inflammation, defined as elevated C-reactive protein (CRP) and/or interleukin-6 (IL-6) within 72 h from birth, with or without positive blood culture. Median serum level of DHA was 0.5 mol% (95% CI (confidence interval) 0.2-0.9, = 0.006) lower than the first postnatal day in infants with early systemic inflammation, compared to infants without signs of inflammation, whereas levels of AA were not statistically different between infants with and without signs of inflammation. In cord blood, lower serum levels of both DHA (correlation coefficient -0.40; = 0.010) and AA (correlation coefficient -0.54; < 0.001) correlated with higher levels of IL-6. Levels of DHA or AA did not differ between infants with and without histological signs of chorioamnionitis or fetal inflammation. In conclusion, serum levels of DHA at birth were associated with the inflammatory response during the early postnatal period in extremely preterm infants.
Chen EM, Armstrong GW, Cox JT, Wu DM, Hoover DR, Del Priore LV, Parikh R. Association of the Affordable Care Act Medicaid Expansion with Dilated Eye Examinations among the United States Population with Diabetes. Ophthalmology 2020;127(7):920-928.Abstract
PURPOSE: To evaluate the association between Medicaid expansion and diabetic dilated eye examinations. DESIGN: A retrospective difference in differences (DiD) analysis using individual-level survey response data from January 1, 2009, to December 31, 2017. PARTICIPANTS: A total of 52 392 survey responses from 50 states and the District of Columbia between 2009 and 2017. Responders were adults aged 18 to 64 years reporting a previous diagnosis of diabetes and a household income below 138% of the US federal poverty line (FPL). METHODS: The Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System data were used to identify survey responders who were asked about the presence of dilated eye examinations from years before and after Medicaid expansion implementation. MAIN OUTCOME MEASURES: The DiD in proportion of dilated eye examinations among diabetic persons aged 18 to 64 years with household incomes below 138% of the FPL between states that did and did not implement Medicaid expansion. RESULTS: Implementation of Medicaid expansion policies was associated with a 1.3% (95% confidence interval [CI], -3.8 to 6.4; P = 0.61), 6.3% (95% CI, 1.3-11.3; P = 0.016), 4.1% (95% CI, -0.8 to 9.0; P = 0.11), and 2.3% (95% CI, -1.6 to 6.2; P = 0.23) increase in the proportion of diabetic persons aged 18 to 64 years with incomes below 138% of the FPL receiving a dilated eye examination within the past year due to Medicaid expansion 1, 2, 3, and 4 cumulative years after expansion, respectively. CONCLUSIONS: Medicaid expansion policies were significantly associated with an increase in dilated eye examination rates within the first 2 years after implementation. However, this increase did not persist beyond this period, with nonsignificant increases 3 and 4 cumulative years after implementation. Healthcare policymakers should be aware that additional measures beyond expanding insurance coverage may be necessary to increase and sustain the rate of dilated eye examinations among diabetic populations.
Solyman O, Elhusseiny AM, Hashem HA. Severe bilateral ankyloblepharon filiforme adnatum. J AAPOS 2020;Abstract
We present a case of bilateral ankyloblepharon filiforme adnatum in 1-day-old girl and describe our surgical approach. The bands connecting the upper and lower eyelids of both eyes were severed using blunt scissors. Point bleeding at the cut bands stopped in 1-2 minutes, without the need for cauterization or compression. The patient was able to open her eyes shortly after the procedure, as she woke up from anesthesia. Examination under general anesthesia showed normal eye examination appropriate for age. Postoperatively, the patient maintained open palpebral fissures. Visual development over 3 years' follow-up was normal.
Kegeles E, Naumov A, Karpulevich EA, Volchkov P, Baranov P. Convolutional Neural Networks Can Predict Retinal Differentiation in Retinal Organoids. Front Cell Neurosci 2020;14:171.Abstract
We have developed a deep learning-based computer algorithm to recognize and predict retinal differentiation in stem cell-derived organoids based on bright-field imaging. The three-dimensional "organoid" approach for the differentiation of pluripotent stem cells (PSC) into retinal and other neural tissues has become a major strategy to recapitulate development. We decided to develop a universal, robust, and non-invasive method to assess retinal differentiation that would not require chemical probes or reporter gene expression. We hypothesized that basic-contrast bright-field (BF) images contain sufficient information on tissue specification, and it is possible to extract this data using convolutional neural networks (CNNs). Retina-specific Rx-green fluorescent protein mouse embryonic reporter stem cells have been used for all of the differentiation experiments in this work. The BF images of organoids have been taken on day 5 and fluorescent on day 9. To train the CNN, we utilized a transfer learning approach: ImageNet pre-trained ResNet50v2, VGG19, Xception, and DenseNet121 CNNs had been trained on labeled BF images of the organoids, divided into two categories (retina and non-retina), based on the fluorescent reporter gene expression. The best-performing classifier with ResNet50v2 architecture showed a receiver operating characteristic-area under the curve score of 0.91 on a test dataset. A comparison of the best-performing CNN with the human-based classifier showed that the CNN algorithm performs better than the expert in predicting organoid fate (84% vs. 67 ± 6% of correct predictions, respectively), confirming our original hypothesis. Overall, we have demonstrated that the computer algorithm can successfully recognize and predict retinal differentiation in organoids before the onset of reporter gene expression. This is the first demonstration of CNN's ability to classify stem cell-derived tissue .
Yang M, Lippestad M, Hodges RR, Fjærvoll HK, Fjærvoll KA, Bair JA, Utheim TP, Serhan CN, Dartt DA. RvE1 uses the LTB receptor BLT1 to increase [Ca] and stimulate mucin secretion in cultured rat and human conjunctival goblet cells. Ocul Surf 2020;18(3):470-482.Abstract
PURPOSE: Specialized pro-resolving lipid mediator resolvin (Rv) E1 stimulates secretion including mucins from conjunctival goblet cells. RvE1 can use both its ChemR23 receptor and the LTB receptor BLT1 to increase [Ca]. The purpose of this study was to determine the expression of ChemR23 and BLT1 and receptors on conjunctival goblet cells and the respective roles these two receptors play in goblet cell responses to RvE1. METHODS: Goblet cells were cultured from male rat or human conjunctiva from both sexes. Western blotting analysis, reverse transcription PCR and immunofluorescence microscopy were used to demonstrate the expression of ChemR23 and BLT1 in conjunctival goblet cells. High molecular weight glycoprotein secretion was determined using an enzyme-linked lectin assay. Signaling pathways were studied by measuring the increase in [Ca] using fura 2/AM. RESULTS: ChemR23 and BLT1 and receptors were present on both rat and human conjunctival goblet cells. The BLT1 inhibitors LY293111 and U75302 significantly blocked RvE1-and LTB-stimulated [Ca] increase. RvE1-and LTB-stimulated [Ca] and secretion increases were blocked by BLT1-targeted siRNA. RvE1-stimulated [Ca] and secretion increases were also blocked by ChemR23-targeted siRNA. Addition of RvE1 2 min before or simultaneously with LTB desensitized the LTB [Ca] response. Addition of RvE1 and LTB simultaneously caused secretion that was decreased compared to either response alone. CONCLUSION: RvE1, in addition to the ChemR23 receptor, uses the BLT1 receptor to increase [Ca] and stimulate secretion in both rat and human cultured conjunctival goblet cells.
Bayraktutar BN, Ozmen CM, Muzaaya N, Dieckmann G, Koseoglu DN, Müller RT, Cruzat A, Cavalcanti BM, Hamrah P. Comparison of clinical characteristics of post-refractive surgery-related and post-herpetic neuropathic corneal pain. Ocul Surf 2020;Abstract
PURPOSE: To compare the clinical characteristics and in vivo confocal microscopy (IVCM) findings of patients with neuropathic corneal pain (NCP) due to refractive surgery (RS-NCP) and herpetic eye disease (H-NCP) to controls. METHODS: Sixteen patients with RS-NCP and 7 patients with H-NCP, and 37 healthy reference age- and sex-matched healthy controls were included to the study. The medical records were reviewed for demographic features, detailed disease history, ocular surface disease index (OSDI), ocular pain assessment survey (OPAS) scores. IVCM images of patients were analyzed and compared to reference controls by two masked observers. RESULTS: The mean pain intensity score for the last 24 h (5.1 ± 2.4 vs. 3.9 ± 1.2; p = 0.27), last 2 weeks (6.1 ± 2.5 vs. 4.8 ± 2.3; p = 0.13) for RS-NCP vs. H-NCP respectively, and quality of life scores (p = 0.23) were similar in both groups. Quality of life, especially mood (p = 0.06) and enjoying life/relations to others (p = 0.10) were affected in both groups, but were not statistically significant between groups. The mean total nerve density was lower in RS-NCP (5702.4 ± 4599.0 μm/mm) compared to their respective controls (26,422.8 ± 4491.0; p < 0.001) and in the H-NCP group (2149.5 ± 2985.9) compared to their respective controls (22,948.8 ± 3169.0; p < 0.001). Alterations in DC density were similar between all groups (38.3 ± 48.0 cells/mm in RS-NCP, 61.0 ± 76.9 in H-NCP, p = 0.95). CONCLUSION: Neuropathic corneal pain patients due to refractive surgery show similar clinical characteristics, pain levels, quality of life impact, and IVCM findings as patients with NCP due to herpetic eye disease.
Ashofteh Yazdi A, Melchor J, Torres J, Faris I, Callejas A, Gonzalez-Andrades M, Rus G. Characterization of non-linear mechanical behavior of the cornea. Sci Rep 2020;10(1):11549.Abstract
The objective of this study was to evaluate which hyperelastic model could best describe the non-linear mechanical behavior of the cornea, in order to characterize the capability of the non-linear model parameters to discriminate structural changes in a damaged cornea. Porcine corneas were used, establishing two different groups: control (non-treated) and NaOH-treated (damaged) corneas (n = 8). NaOH causes a chemical burn to the corneal tissue, simulating a disease associated to structural damage of the stromal layer. Quasi-static uniaxial tensile tests were performed in nasal-temporal direction immediately after preparing corneal strips from the two groups. Three non-linear hyperelastic models (i.e. Hamilton-Zabolotskaya model, Ogden model and Mooney-Rivlin model) were fitted to the stress-strain curves obtained in the tensile tests and statistically compared. The corneas from the two groups showed a non-linear mechanical behavior that was best described by the Hamilton-Zabolotskaya model, obtaining the highest coefficient of determination (R > 0.95). Moreover, Hamilton-Zabolotskaya model showed the highest discriminative capability of the non-linear model parameter (Parameter A) for the tissue structural changes between the two sample groups (p = 0.0005). The present work determines the best hyperelastic model with the highest discriminative capability in description of the non-linear mechanical behavior of the cornea.
Nartker MS, Alaoui-Soce A, Wolfe JM. Visual search errors are persistent in a laboratory analog of the incidental finding problem. Cogn Res Princ Implic 2020;5(1):32.Abstract
When radiologists search for a specific target (e.g., lung cancer), they are also asked to report any other clinically significant "incidental findings" (e.g., pneumonia). These incidental findings are missed at an undesirably high rate. In an effort to understand and reduce these errors, Wolfe et al. (Cognitive Research: Principles and Implications 2:35, 2017) developed "mixed hybrid search" as a model system for incidental findings. In this task, non-expert observers memorize six targets: half of these targets are specific images (analogous to the suspected diagnosis in the clinical task). The other half are broader, categorically defined targets, like "animals" or "cars" (analogous to the less well-specified incidental findings). In subsequent search through displays for any instances of any of the targets, observers miss about one third of the categorical targets, mimicking the incidental finding problem. In the present paper, we attempted to reduce the number of errors in the mixed hybrid search task with the goal of finding methods that could be deployed in a clinical setting. In Experiments 1a and 1b, we reminded observers about the categorical targets by inserting non-search trials in which categorical targets were clearly marked. In Experiment 2, observers responded twice on each trial: once to confirm the presence or absence of the specific targets, and once to confirm the presence or absence of the categorical targets. In Experiment 3, observers were required to confirm the presence or absence of every target on every trial using a checklist procedure. Only Experiment 3 produced a marked decline in categorical target errors, but at the cost of a substantial increase in response time.
Jakobiec FA, Hanbazazh M, Barrantes PC, Chodosh J. Adult Primary Capillary Hemangioma of the Sclera: A Previously Undescribed Entity With a Review of Epibulbar Vascular Lesions. Ophthalmic Plast Reconstr Surg 2020;36(4):327-333.Abstract
PURPOSE: The objective of this article is to document a unique case of a primary hemangioma and review epibulbar vascular tumors of the conjunctiva and episclera. METHODS: A case report with detailed histopathologic, histochemical, and immunohistochemical studies coupled with a comprehensive review of the relevant literature with a tabulation of previously reported epibulbar vascular lesions was performed. RESULTS: A vascular tumor developed in a 46-year-old woman over 2-3 months that histopathologically was located in the superficial third of the normally avascular sclera and was composed of capillary caliber vessels. CD31 and CD34 positivity established the vascular nature of the lesion. Despite its adult onset, the tumor was also glut-1 positive, a vascular characteristic of childhood capillary hemangiomas that will ultimately involute. Smooth muscle actin was positive in the endothelial cells and associated pericytes. An ectatic muscular vessel identified in the midst of the lesion was interpreted as an anomalous intrascleral branch of an epibulbar anterior ciliary artery, where it perforated the sclera in the vicinity of the insertion of an extraocular rectus muscle. It was deduced to be the source of the capillary proliferation. A literature review failed to identify any previously reported epibulbar vascular tumor that originated primarily in the sclera or secondarily infiltrated this ocular tunic. CONCLUSION: An adult primary capillary intrascleral neoplasm is described as the rarest of all epibulbar vascular tumors and in keeping with the exceptional status of the ocular endothelium was glut-1 positive. This lesion must be distinguished from an array of other common and esoteric epibulbar vascular conditions.
Parikh D, Armstrong G, Liou V, Husain D. Advances in Telemedicine in Ophthalmology. Semin Ophthalmol 2020;:1-6.Abstract
Telemedicine is the provision of healthcare-related services from a distance and is poised to move healthcare from the physician's office back into the patient's home. The field of ophthalmology is often at the forefront of technological advances in medicine including telemedicine and the use of artificial intelligence. Multiple studies have demonstrated the reliability of tele-ophthalmology for use in screening and diagnostics and have demonstrated benefits to patients, physicians, as well as payors. There remain obstacles to widespread implementation, but recent legislation and regulation passed due to the devastating COVID-19 pandemic have helped to reduce some of these barriers. This review describes the current status of tele-ophthalmology in the United States including benefits, hurdles, current programs, technology, and developments in artificial intelligence. With ongoing advances patients may benefit from improved detection and earlier treatment of eye diseases, resulting in better care and improved visual outcomes.
McKay TB, Schlötzer-Schrehardt U, Pal-Ghosh S, Stepp MA. Integrin: Basement membrane adhesion by corneal epithelial and endothelial cells. Exp Eye Res 2020;:108138.Abstract
Integrins mediate adhesion of cells to substrates and maintain tissue integrity by facilitating mechanotransduction between cells, the extracellular matrix, and gene expression in the nucleus. Changes in integrin expression in corneal epithelial cells and corneal endothelial cells impacts their adhesion to the epithelial basement membrane (EpBM) and Descemet's membrane, respectively. Integrins also play roles in assembly of basement membranes by both activating TGFβ1 and other growth factors. Over the past two decades, this knowledge has been translated into methods to grow corneal epithelial and endothelial cells in vitro for transplantation in the clinic thereby transforming clinical practice and quality of life for patients. Current knowledge on the expression and function of the integrins that mediate adhesion to the basement membrane expressed by corneal epithelial and endothelial cells in health and disease is summarized. This is the first review to discuss similarities and differences in the integrins expressed by both cell types.