Park J, Armstrong G, Cestari D. Spontaneous Superior Ophthalmic Vein Thrombosis in a Transgender Man with Systemic Lupus Erythematosus. LGBT Health. 2019;6(4):202–204.
- Home
- All
All
All | 3856 Publications
Ponce C, Xiao W, Schade P, Hartmann T, Kreiman G, Livingstone M. Evolving Images for Visual Neurons Using a Deep Generative Network Reveals Coding Principles and Neuronal Preferences. Cell. 2019;177(4):999–1009.e10.
What specific features should visual neurons encode, given the infinity of real-world images and the limited number of neurons available to represent them? We investigated neuronal selectivity in monkey inferotemporal cortex via the vast hypothesis space of a generative deep neural network, avoiding assumptions about features or semantic categories. A genetic algorithm searched this space for stimuli that maximized neuronal firing. This led to the evolution of rich synthetic images of objects with complex combinations of shapes, colors, and textures, sometimes resembling animals or familiar people, other times revealing novel patterns that did not map to any clear semantic category. These results expand our conception of the dictionary of features encoded in the cortex, and the approach can potentially reveal the internal representations of any system whose input can be captured by a generative model.
Raghuram A, Hunter D, Waber D. Accurately Assessing Visual Deficits in Children With Developmental Dyslexia-Reply. JAMA Ophthalmol. 2019;
Rosales MAB, Shu D, Iacovelli J, Saint-Geniez M. Correction: Loss of PGC-1α in RPE induces mesenchymal transition and promotes retinal degeneration. Life Sci Alliance. 2019;2(3).
Rosales MAB, Shu D, Iacovelli J, Saint-Geniez M. Loss of PGC-1α in RPE induces mesenchymal transition and promotes retinal degeneration. Life Sci Alliance. 2019;2(3).
The retinal pigment epithelium (RPE) supports visual processing and photoreceptor homeostasis via energetically demanding cellular functions. Here, we describe the consequences of repressing peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1α), a master regulator of mitochondrial function and biogenesis, on RPE epithelial integrity. The sustained silencing of PGC-1α in differentiating human RPE cells affected mitochondria/autophagy function, redox state, and impaired energy sensor activity ultimately inducing epithelial to mesenchymal transition (EMT). Adult conditional knockout of PGC-1 coactivators in mice resulted in rapid RPE dysfunction and transdifferentiation associated with severe photoreceptor degeneration. RPE anomalies were characteristic of autophagic defect and mesenchymal transition comparable with the ones observed in age-related macular degeneration. These findings demonstrate that PGC-1α is required to maintain the functional and phenotypic status of RPE by supporting the cells' oxidative metabolism and autophagy-mediated repression of EMT.
Shu D, Hutcheon A, Zieske J, Guo X. Epidermal Growth Factor Stimulates Transforming Growth Factor-Beta Receptor Type II Expression In Corneal Epithelial Cells. Sci Rep. 2019;9(1):8079.
We previously demonstrated that inhibition of epidermal growth factor receptor (EGFR) slowed corneal epithelial migration. Here we examine the effect of EGF on transforming growth factor-beta receptor II (TGF-βRII) in a corneal wound-healing model and primary human corneal epithelial cells (pHCE). Corneal debridement wounds were made and allowed to heal ± Tyrphostin AG1478 (EGFR inhibitor), and assayed for EGFR activation and EGFR and TGF-βRII localization. Primary HCE were treated with EGF ± U0126 (MEK inhibitor) and assayed for TGF-βRII expression. EGFR activation was maximal 15 minutes after wounding and localized in the migrating epithelial cells. TGF-βRII localization was also observed in the migrating epithelium and was reduced when EGFR was blocked. When pHCE were treated with EGF for 6 hours, the cells produced enhanced levels of TGF-βRII, which was blocked by U0126. Downstream signaling pathways of MEK (p38 and ERK1/2) were then examined, and TGF-β1 and EGF were found to have differential effects on the phosphorylation of p38 and ERK1/2, with TGF-β1 upregulating p-p38 but not pERK1/2 and EGF upregulating pERK1/2 but not p-p38. Taken together, these data indicate that EGF stimulates TGF-βRII through ERK1/2 and EGFR signaling, suggesting interplay between EGF- and TGF-β-signaling pathways during corneal wound repair.
Smits D, Elze T, Wang H, Pasquale L. Machine Learning in the Detection of the Glaucomatous Disc and Visual Field. Semin Ophthalmol. 2019;:1–11.
Glaucoma is the leading cause of irreversible blindness worldwide. Early detection is of utmost importance as there is abundant evidence that early treatment prevents disease progression, preserves vision, and improves patients' long-term quality of life. The structure and function thresholds that alert to the diagnosis of glaucoma can be obtained entirely via digital means, and as such, screening is well suited to benefit from artificial intelligence and specifically machine learning. This paper reviews the concepts and current literature on the use of machine learning for detection of the glaucomatous disc and visual field.
Szczotka-Flynn L, Maguire M, Ying GS, Lin M, Bunya V, Dana R, Asbell P, Group DEAM (DREAM) SR. Impact of Dry Eye on Visual Acuity and Contrast Sensitivity: Dry Eye Assessment and Management Study. Optom Vis Sci. 2019;96(6):387–396.
SIGNIFICANCE: Identification of the association of specific signs of dry eye disease with specific visual function deficits may allow for more targeted approaches to treatment. PURPOSE: The purpose of this study was to explore the association of dry eye signs and symptoms with visual acuity (VA) and contrast sensitivity in the Dry Eye Assessment and Management study. METHODS: Baseline data from participants in the Dry Eye Assessment and Management study were used in this secondary cross-sectional analysis. Standardized procedures were used to obtain results on the Ocular Surface Disease Index (OSDI), high-contrast logMAR VA, contrast sensitivity, tear film debris, tear breakup time (TBUT), corneal fluorescein staining, meibomian gland evaluation, conjunctival lissamine green staining, and Schirmer test scores. Generalized linear models that included age, refractive error status, and cataract status were used to assess the association between VA and contrast sensitivity with OSDI score and each dry eye sign. The Hochberg procedure was used to account for multiple comparisons. RESULTS: Among 487 participants (974 eyes), worse VA was associated with worse mean score on the OSDI vision subscale (39.4 for VA 20/32 or worse vs. 32.4 for VA 20/16 or better; adjusted linear trend, P = .02); scores were not associated with contrast sensitivity. Severe meibomian gland plugging and abnormal secretions were associated with worse mean log contrast sensitivity (1.48 for severe vs. 1.54 for not plugged [P = .04] and 1.49 for obstructed vs. 1.57 for clear [P = .002], respectively). Longer TBUT was associated with better mean log contrast sensitivity (1.57 for TBUT >5 seconds and 1.51 for TBUT ≤2 seconds, P < .0001). CONCLUSIONS: Worse VA rather than worse contrast sensitivity drives vision-related symptoms in dry eye. Greater tear film instability was associated with worse contrast sensitivity.
Unzu C, Planet E, Brandenberg N, Fusil F, Cassano M, Perez-Vargas J, Friedli M, Cosset FL, Lutolf M, Wildhaber B, Trono D. Pharmacological Induction of a Progenitor State for the Efficient Expansion of Primary Human Hepatocytes. Hepatology. 2019;69(5):2214–2231.
The liver is an organ with strong regenerative capacity, yet primary hepatocytes have a low amplification potential in vitro, a major limitation for the cell-based therapy of liver disorders and for ex vivo biological screens. Induced pluripotent stem cells (iPSCs) may help to circumvent this obstacle but often harbor genetic and epigenetic abnormalities, limiting their potential. Here, we describe the pharmacological induction of proliferative human hepatic progenitor cells (HPCs) through a cocktail of growth factors and small molecules mimicking the signaling events involved in liver regeneration. Human HPCs from healthy donors and pediatric patients proliferated vigorously while maintaining their genomic stability and could be redifferentiated in vitro into metabolically competent cells that supported the replication of hepatitis B and delta viruses. Redifferentiation efficiency was boosted by three-dimensional culture. Finally, transcriptome analysis showed that HPCs were more closely related to mature hepatocytes than iPSC-derived hepatocyte-like cells were. Conclusion: HPC induction holds promise for a variety of applications such as ex vivo disease modeling, personalized drug testing or metabolic studies, and development of a bioartificial liver.
Wang J, Miller J. For Mass Eye and Ear Special Issue: Optical Coherence Tomography Angiography: Review of Current Technical Aspects and Applications in Chorioretinal Disease. Semin Ophthalmol. 2019;:1–7.
Optical coherence tomography angiography (OCT-A) has enabled fast, non-invasive, high-resolution visualization of vasculature within the eye. In the past few years, it has become increasingly utilized for a range of disorders including age-related macular degeneration, diabetic retinopathy, retinal vein occlusions, and uveitis among others. This article reviews technical aspects of OCT-A, its applications in chorioretinal disease, and known limitations of the technology.
Wiegand I, Wolfe J. Age doesn’t matter much: hybrid visual and memory search is preserved in older adults. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2020;27(2):220–253.
We tested younger and older observers' attention and long-term memory functions in a "hybrid search" task, in which observers look through visual displays for instances of any of several types of targets held in memory. Apart from a general slowing, search efficiency did not change with age. In both age groups, reaction times increased linearly with the visual set size and logarithmically with the memory set size, with similar relative costs of increasing load (Experiment 1). We replicated the finding and further showed that performance remained comparable between age groups when familiarity cues were made irrelevant (Experiment 2) and target-context associations were to be retrieved (Experiment 3). Our findings are at variance with theories of cognitive aging that propose age-specific deficits in attention and memory. As hybrid search resembles many real-world searches, our results might be relevant to improve the ecological validity of assessing age-related cognitive decline.
Zieske J, Hutcheon A, Guo X. Extracellular Vesicles and Cell-Cell Communication in the Cornea. Anat Rec (Hoboken). 2020;303(6):1727–1734.
One question that has intrigued cell biologists for many years is, "How do cells interact to influence one another's activity?" The discovery of extracellular vesicles (EVs) and the fact that they carry cargo, which directs cells to undergo changes in morphology and gene expression, has revolutionized this field of research. Little is known regarding the role of EVs in the cornea; however, we have demonstrated that EVs isolated from corneal epithelial cells direct corneal keratocytes to initiate fibrosis. Intriguingly, our data suggest that EVs do not penetrate epithelial basement membrane (BM), perhaps providing a mechanism explaining the importance of BM in the lack of scarring in scrape wounds. Since over 100-million people worldwide suffer from visual impairment as a result of corneal scarring, the role of EVs may be vital to understanding the mechanisms of wound repair. Therefore, we investigated EVs in ex vivo and in vivo-like three-dimensional cultures of human corneal cells using transmission electron microscopy. Some of the major findings were all three major cell types (epithelial, fibroblast, and endothelial cells) appear to release EVs, EVs can be identified using TEM, and EVs appeared to be involved in cell-cell communication. Interestingly, while our previous publication suggests that EVs do not penetrate the epithelial BM, it appears that EVs penetrate the much thicker endothelial BM (Descemet's membrane). These findings indicate the huge potential of EV research in the cornea and wound healing, and suggest that during homeostasis the endothelium and stromal cells are in communication. Anat Rec, 2019. © 2019 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
Silva RN, Chiou C, Wang M, Wang H, Shoji M, Chou J, D’Souza E, Greenstein S, Brauner S, Alves M, Pasquale L, Shen L. Microvasculature of the Optic Nerve Head and Peripapillary Region in Patients With Primary Open-Angle Glaucoma. J Glaucoma. 2019;28(4):281–288.
PURPOSE: To assess optic nerve head (ONH) and peripapillary microvasculature in primary open-angle glaucoma (POAG) of mild to moderate severity using swept-source optical coherence tomography angiography (OCTA). MATERIALS AND METHODS: In a cross-sectional study, swept-source OCTA images were analyzed for 1 eye from each of 30 POAG patients with glaucomatous Humphrey visual field loss and 16 controls. The anatomic boundary of ONH was manually delineated based on Bruch's membrane opening and large vessels were removed from en face angiography images to measure vessel density (VD) and the integrated OCTA by ratio analysis signal (IOS), suggestive of flow, in the ONH and peripapillary region. POAG subgroup analysis was performed based on a history of disc hemorrhage (DH) matched by visual field mean deviation (MD). RESULTS: POAG (mean MD±SD, -3.3±3.0 dB) and control groups had similar demographic characteristics and intraocular pressure on the day of imaging. Groups did not differ in superficial ONH VD or flow indicated by IOS (P≥0.28). POAG eyes showed significantly lower VD (39.4%±4.0%) and flow (38.8%±5.6%) in deep ONH, peripapillary VD (37.9%±2.9%) and flow (43.6%±4.0%) compared with control eyes (44.1%±5.1%, 44.7%±6.9%, 40.7%±1.7%, 47.8%±2.5%, respectively; P≤0.007 for all). In the subgroup analysis, POAG eyes with (n=14) and without DH (n=16) had similar measured OCTA parameters (P>0.99 for all). CONCLUSIONS: The image processing methodology based on the anatomic boundary of ONH demonstrated compromised microvasculature in the deep ONH and peripapillary region in eyes with mild to moderate POAG, regardless of the history of DH.
Raghuram A, Cotter S, Gowrisankaran S, Kanji J, Howell D, Meehan W, Shah A. Post-Concussion: Receded Near Point of Convergence is Not Diagnostic of Convergence Insufficiency. Am J Ophthalmol. 2019;
PURPOSE: To determine the frequency of receded near point of convergence (NPC) in patients with chronic concussion-related symptoms, and among those with receded NPC to enumerate the frequency of convergence insufficiency and other oculomotor disorders. STUDY: Design: Retrospective cross-sectional study METHODS: Clinic charts were retrospectively reviewed for the prior 3.5 years to identify all patients <21 years old who were >28 days post-concussion, had chronic concussion-related symptoms, had normal visual acuity, and received a comprehensive sensorimotor examination. The frequency of receded NPC and oculomotor diagnoses were determined. RESULTS: Of the 83 eligible patients, 74 (89%) had receded NPC. Of these, 70 (95%) had oculomotor disorders; 30 (41%) had disorders of accommodation only, 21 (28%) had convergence insufficiency and accommodation deficits, and 6 (8%) had convergence insufficiency only. Six (8%) had a convergence deficit other than convergence insufficiency (all with concurrent accommodative disorders), 4 (5%) had both a non-specific vergence dysfunction and accommodation deficits, 2 (3%) had convergence excess only, and 1 (1%) had both convergence excess and accommodative deficits. CONCLUSION: A receded NPC was present in the majority of young patients with chronic post-concussion symptoms. Associated with numerous underlying oculomotor dysfunctions, the clinical finding of a receded NPC is not synonymous with the diagnosis of convergence insufficiency. Because treatment options for the various oculomotor dysfunctions differ, it is prudent that these patients undergo a thorough examination of their vergence and accommodative systems so that an accurate diagnosis can be made and appropriate treatment prescribed.
Marmalidou A, Palioura S, Dana R, Kheirkhah A. Medical and surgical management of conjunctivochalasis. Ocul Surf. 2019;
Conjunctivochalasis (CCH) is a bilateral conjunctival condition characterized by loose, redundant conjunctival folds, typically in the inferior bulbar conjunctiva. It is a common cause of ocular irritation, especially in older age. For asymptomatic CCH, no treatment is necessary. For treatment of symptomatic CCH, however, a variety of medical and surgical approaches are currently available, which will be thoroughly appraised in this review article. The first step in the management is medical therapy, which involves enhanced lubrication and use of anti-inflammatory medications. In refractory cases, a surgical approach may be undertaken for symptom relief. Several techniques have been described for this, with varying success rates. These include conjunctival cauterization, conjunctival excision, scleral fixation of the conjunctiva, conjunctival ligation, laser conjunctivoplasty, and radiowave electrosurgery. Among these, conjunctival cauterization and excision of the redundant conjunctiva, with or without tissue grafting, have gained popularity.
Lužnik Z, Oellerich S, Roesch K, Yin J, Zumbansen M, Franken L, Melles G, Dana R. Descemet Membrane Endothelial Keratoplasty Failure Associated with Innate Immune Activation. Ophthalmology. 2019;126(10):1462–1464.
Khateb S, Nassisi M, Bujakowska K, Méjécase C, Condroyer C, Antonio A, Foussard M, Démontant V, Mohand-Saïd S, Sahel JA, Zeitz C, Audo I. Longitudinal Clinical Follow-up and Genetic Spectrum of Patients With Rod-Cone Dystrophy Associated With Mutations in PDE6A and PDE6B. JAMA Ophthalmol. 2019;
Importance: A precise phenotypic characterization of retinal dystrophies is needed for disease modeling as a basis for future therapeutic interventions. Objective: To compare genotype, phenotype, and structural changes in patients with rod-cone dystrophy (RCD) associated with mutations in PDE6A or PDE6B. Design, Setting, and Participants: In a retrospective cohort study conducted in Paris, France, from January 2007 to September 2017, 54 patients from a cohort of 1095 index patients with RCD underwent clinical examination, including personal and familial history, best-corrected visual acuity (BCVA), color vision, slitlamp examination, full-field electroretinography, kinetic visual fields (VFs), retinophotography, optical coherence tomography, near-infrared fundus autofluorescence, and short-wavelength fundus autofluorescence imaging. Genotyping was performed using microarray analysis, targeted next-generation sequencing, and Sanger sequencing validation with familial segregation when possible. Data were analyzed from September 1, 2017, to February 1, 2018. Clinical variables were subsequently analyzed in 2018. Main Outcomes and Measures: Phenotype and genotype comparison of patients carrying mutations in PDE6A or PDE6B. Results: Of the 54 patients included in the study, 19 patients of 17 families (11 women [58%]; mean [SD] age at diagnosis, 14.83 [10.63] years) carried pathogenic mutations in PDE6A, and 35 patients of 26 families (17 women [49%]; mean [SD] age at diagnosis, 21.10 [11.56] years) had mutations in PDE6B, accounting for prevalences of 1.6% and 2.4%, respectively. Among 49 identified genetic variants, 14 in PDE6A and 15 in PDE6B were novel. Overall, phenotypic analysis revealed no substantial differences between the 2 groups except for night blindness as a presenting symptom that was noted to be more prevalent in the PDE6A than PDE6B group (80% vs 37%, respectively; P = .005). The mean binocular BCVA and VF decrease over time (measured as mean individual slopes coefficients) was comparable between patients with PDE6A and PDE6B mutations: 0.04 (0.12) vs 0.02 (0.05) for BCVA (P = .89) and 14.33 (7.12) vs 13.27 (6.77) for VF (P = .48). Conclusions and Relevance: Mutations in PDE6A and PDE6B accounted for 1.6% and 2.4%, respectively, in a cohort of French patients with RCD. The functional and structural findings reported may constitute the basis of disease modeling that might be used for better prognostic estimation and candidate selection for photoreceptor therapeutic rescue.
Kempen J, Pistilli M, Begum H, Fitzgerald T, Liesegang T, Payal A, Zebardast N, Bhatt N, Foster S, Jabs D, Levy-Clarke G, Nussenblatt R, Rosenbaum J, Sen N, Suhler E, Thorne J, Group SITED (SITE) CSR. Remission of Non-Infectious Anterior Scleritis: Incidence and Predictive Factors. Am J Ophthalmol. 2021;223:377–395.
PURPOSE: To assess how often non-infectious anterior scleritis remits and identify predictive factors. METHODS: Our retrospective cohort study at four ocular inflammation subspecialty centers collected data for each affected eye/patient at every visit from center inception (1978, 1978, 1984, 2005) until 2010. Remission was defined as inactivity of disease off all suppressive medications at all visits spanning at least three consecutive months or at all visits up to the last visit (to avoid censoring patients stopping follow-up after remission). Factors potentially predictive of remission were assessed using Cox regression models. RESULTS: During 1,906 years' aggregate follow-up of 832 affected eyes, remission occurred in 214 (170 of 584 patients). Median time-to-remission of scleritis = 7.8 years (95% confidence interval [CI]: 5.7, 9.5). More remissions occurred earlier than later during follow-up. Factors predictive of less scleritis remission included scleritis bilaterality (adjusted hazard ratio [aHR] = 0.46, 95% CI: 0.32-0.65); and diagnosis with any systemic inflammatory disease (aHR = 0.36, 95% CI: 0.23-0.58), or specifically with Rheumatoid Arthritis (aHR = 0.22), or Granulomatosis with Polyangiitis (aHR = 0.08). Statin treatment (aHR = 1.53, 95% CI: 1.03-2.26) within ≤90 days was associated with more remission incidence. CONCLUSIONS: Our results suggest scleritis remission occurs more slowly in anterior scleritis than in newly diagnosed anterior uveitis or chronic anterior uveitis, suggesting that attempts at tapering suppressive medications is warranted after long intervals of suppression. Remission is less frequently achieved when systemic inflammatory diseases are present. Confirmatory studies of whether adjunctive statin treatment truly can enhance scleritis remission (as suggested here) are needed.
Jaffe G, Foster S, Pavesio C, Paggiarino D, Riedel G. Effect of an Injectable Fluocinolone Acetonide Insert on Recurrence Rates in Chronic Noninfectious Uveitis Affecting the Posterior Segment: Twelve-Month Results. Ophthalmology. 2019;126(4):601–610.
PURPOSE: To assess the safety and efficacy of an intravitreal fluocinolone acetonide (FA) insert to manage inflammation associated with chronic noninfectious posterior uveitis. DESIGN: Multicenter, randomized, prospective, doubled-masked, sham-controlled, 3-year phase 3 clinical trial. PARTICIPANTS: One hundred twenty-nine participants with recurrent noninfectious posterior uveitis were assigned randomly to FA insert (n = 87) or sham injection (n = 42). The more severely affected eye in participants with bilateral disease was designated as the study eye. METHODS: The insert (FA, 0.18 mg) was injected into the vitreous cavity; sham injection mimicked the insert delivery procedure. Ophthalmic examinations, OCT, and ocular tolerability and discomfort assessments were conducted; study visits were on days 7 and 28 and months 2, 3, 6, 9, and 12. Uveitis recurrence was treated as needed. The 6-month recurrence rate was the primary outcome measure. RESULTS: The 6-month (28% and 91%) and 12-month (38% and 98%) uveitis recurrence rates were significantly lower (P < 0.001) with FA insert vs. sham, respectively. Fewer recurrences per study eye (mean, 0.7 vs. 2.5), lower incidence of 15-letter or more decrease in best-corrected visual acuity (14% vs. 31%), and reduced systemic (19% vs. 40%) and local (7% vs. 62%) uveitis adjunctive treatments were observed with FA insert vs. sham, respectively. The FA insert group showed higher rates of cataract. Intraocular pressure-lowering treatment use was similar between groups. No deaths, treatment-related study discontinuations, or unanticipated safety signals were observed through 12 months. CONCLUSIONS: Chronic noninfectious posterior uveitis was managed successfully in this study population; FA insert eyes experienced fewer uveitis recurrence episodes, required fewer adjunctive treatments, and demonstrated less visual acuity loss compared with sham eyes. The FA insert treatment group showed higher rates of cataract; delivery by injection was not associated with an increase in ocular adverse events or any other safety measures not typically associated with local steroid use, suggesting the procedure is appropriate for an office setting.
Hutcheon A, Zieske J, Guo X. 3D in vitro model for human corneal endothelial cell maturation. Exp Eye Res. 2019;184:183–191.
Corneal endothelium is a cellular monolayer positioned on the Descemet's membrane at the anterior cornea, and it plays a critical role in maintaining corneal clarity. Our present study examines the feasibility of utilizing our 3-dimensional (3D) corneal stromal construct, which consists of human corneal fibroblasts (HCF) and their self-assembled matrix, to observe the development and maturation of human corneal endothelial cells (HCEndoCs) in a co-culture model. Three-dimensional HCF constructs were created by growing the HCFs on Transwell membranes in Eagles' minimum essential medium (EMEM) + 10% FBS + 0.5 mM Vitamin C (VitC) for about 4 weeks. HCEndoCs, either primary (pHCEndoC) or cell line (HCEndoCL), were either seeded in chamber slides, directly on the Transwell membranes, or on the 3D HCF constructs and cultivated for 5 days or 2 weeks. The HCEndoCs that were seeded directly on the Transwell membranes were exposed indirectly to HCF by culturing the HCF on the plate beneath the membrane. Cultures were examined for morphology and ultrastructure using light and transmission electron microscopy (TEM). In addition, indirect-immunofluorescence microscopy (IF) was used to examine tight junction formation (ZO-1), maturation (ALDH1A1), basement membrane formation (Laminin), cell proliferation (Ki67), cell death (caspase-3), and fibrotic response (CTGF). As expected, both pHCEndoCs and HCEndoCLs formed monolayers on the constructs; however, the morphology of the HCEndoCLs appeared to be similar to that seen in vivo, uniform and closely packed, whereas the pHCEndoCs remained elongated. The IF data showed that laminin localization was present in the HCEndoCs' cytoplasm as cell-cell contact increased, and when they were grown in the 3D co-culture, the beginnings of what appears to be a continuous DM-like structure was observed. In addition, in co-cultures, ALDH1A1-positive HCEndoCs were present, ZO-1 expression localized within the tight junctions, minimal numbers of HCEndoCs were Ki67-or Caspase-3-positive, and CTGF was positive in both the HCEndoCs cytoplasm and the matrix of the co-culture. Also, laminin localization was stimulated in HCEndoCs upon indirect stimuli secreted by HCF. The present data suggests our 3D co-culture model is useful for studying corneal endothelium maturation in vitro since the co-culture promotes new DM-like formation, HCEndoCs develop in vivo-like characteristics, and the fibrotic response is activated. Our current findings are applicable to understanding the implications of corneal endothelial injection therapy, such as if the abnormal DM has to be removed from the patient, the newly injected endothelial cells will seed onto the wound area and deposit a new DM-like membrane. However, caution should be observed and as much of the normal DM should be left intact since removal of the DM can cause a posterior stromal fibrotic response.
Haque M, Lei F, Xiong X, Das JK, Ren X, Fang D, Salek-Ardakani S, Yang JM, Song J. Stem cell-derived tissue-associated regulatory T cells suppress the activity of pathogenic cells in autoimmune diabetes. JCI Insight. 2019;4(7).
The autoantigen-specific Tregs from pluripotent stem cells (PSCs), i.e., PSC-Tregs, have the ability to suppress autoimmunity. PSC-Tregs can be programmed to be tissue associated and to infiltrate into local inflamed tissues to suppress autoimmune responses after adoptive transfer. Nevertheless, the mechanisms by which the autoantigen-specific PSC-Tregs suppress the autoimmune response remain to be fully elucidated. In this study, we generated functional autoantigen-specific Tregs from the induced PSC (iPSCs), i.e., iPSC-Tregs, and investigated the underlying mechanisms of autoimmunity suppression by these Tregs in a type 1 diabetes (T1D) murine model. A double-Tg mouse model of T1D was established in F1 mice, in which the first generation of RIP-mOVA Tg mice that were crossed with OT-I T cell receptor (TCR) Tg mice was challenged with vaccinia viruses expressing OVA (VACV-OVA). We show that adoptive transfer of OVA-specific iPSC-Tregs greatly suppressed autoimmunity in the animal model and prevented the insulin-secreting pancreatic β cells from destruction. Further, we demonstrate that the adoptive transfer significantly reduced the expression of ICAM-1 in the diabetic pancreas and inhibited the migration of pathogenic CD8+ T cells and the production of the proinflammatory IFN-γ in the pancreas. These results indicate that the stem cell-derived tissue-associated Tregs can robustly accumulate in the diabetic pancreas, and, through downregulating the expression of ICAM-1 in the local inflamed tissues and inhibiting the production of proinflammatory cytokine IFN-γ, suppress the migration and activity of the pathogenic immune cells that cause T1D.
Barrett, Houston K. Update on the Clinical Approach to Spatial Neglect. Curr Neurol Neurosci Rep. 2019;19(5):25.
PURPOSE OF REVIEW: Spatial neglect is asymmetric orienting and action after a brain lesion, causing functional disability. It is common after a stroke; however, it is vastly underdocumented and undertreated. This article addresses the implementation gap in identifying and treating spatial neglect, to reduce disability and improve healthcare costs and burden. RECENT FINDINGS: Professional organizations published recommendations to implement spatial neglect care. Physicians can lead an interdisciplinary team: functionally relevant spatial neglect assessment, evidence-based spatial retraining, and integrated spatial and vision interventions can optimize outcomes. Research also strongly suggests spatial neglect adversely affects motor systems. Spatial neglect therapy might thus "kick-start" rehabilitation and improve paralysis recovery. Clinicians can implement new techniques to detect spatial neglect and lead interdisciplinary teams to promote better, integrated spatial neglect care. Future studies of brain imaging biomarkers to detect spatial neglect, and real-world applicability of prism adaptation treatment, are needed.
Botten N, Hodges R, Li D, Bair J, Shatos M, Utheim T, Serhan C, Dartt DA. Resolvin D2 elevates cAMP to increase intracellular [Ca] and stimulate secretion from conjunctival goblet cells. FASEB J. 2019;33(7):8468–8478.
Under physiologic conditions, conjunctival goblet cells (CGCs) secrete mucins into the tear film to preserve ocular surface homeostasis. Specialized proresolving mediators (SPMs), like resolvins (Rvs), regulate secretion from CGCs and actively terminate inflammation. The purpose of this study was to determine if RvD2 stimulated mucin secretion and to investigate the cellular signaling components. Goblet cells were cultured from rat conjunctiva. Secretion was measured by an enzyme-linked lectin assay, change in intracellular [Ca] ([Ca]) using Fura-2, and cellular cAMP levels by ELISA. RvD2 (10-10 M) stimulated secretion, increased cellular cAMP levels and the [Ca]. RvD2-stimulated increase in [Ca] and secretion was blocked by Ca chelator 1,2-bis(2-aminophenoxy)ethane-,,','-tetraacetic acid tetrakis and the PKA inhibitor -[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride but not by the cAMP exchange protein inhibitor α-[2-(3-chlorophenyl)hydrazinylidene]-5-(1,1-dimethylethyl)-b-oxo-3-isoxazolepropanenitrile. Forskolin, 3-isobutyl-1-methylxanthine, and 8-bromo-cAMP (8-Br-cAMP) increased [Ca]. Increasing cAMP with 8-Br-cAMP inhibited the increase in [Ca] stimulated by the cAMP-independent agonist cholinergic agonist carbachol. In conclusion, RvD2 uses both cellular cAMP and [Ca] to stimulate glycoconjugate secretion from CGCs, but the interaction of cAMP and [Ca] is context dependent. Thus RvD2 likely assists in the maintenance of the mucous layer of the tear film to sustain ocular surface homeostasis and has potential as a novel treatment for dry eye disease.-Botten, N., Hodges, R. R., Li, D., Bair, J. A., Shatos, M. A., Utheim, T. P., Serhan, C. N., Dartt, D. A. Resolvin D2 elevates cAMP to increase intracellular [Ca] and stimulate secretion from conjunctival goblet cells.
Berner D, Hoja U, Zenkel M, Ross JJ, Uebe S, Paoli D, Frezzotti P, Rautenbach R, Ziskind A, Williams S, Carmichael T, Ramsay M, Topouzis F, Chatzikyriakidou A, Lambropoulos A, Sundaresan P, Ayub H, Akhtar F, Qamar R, Zenteno J, Cruz-Aguilar M, Astakhov Y, Dubina M, Wiggs J, Ozaki M, Kruse F, Aung T, Reis A, Khor CC, Pasutto F, Schlötzer-Schrehardt U. The protective variant rs7173049 at LOXL1 locus impacts on retinoic acid signaling pathway in pseudoexfoliation syndrome. Hum Mol Genet. 2019;
LOXL1 (lysyl oxidase-like 1) has been identified as the major effect locus in pseudoexfoliation (PEX) syndrome, a fibrotic disorder of the extracellular matrix and frequent cause of chronic open-angle glaucoma. However, all known PEX-associated common variants show allele effect reversal in populations of different ancestry, casting doubt on their biological significance. Based on extensive LOXL1 deep sequencing, we report here the identification of a common noncoding sequence variant, rs7173049A>G, located downstream of LOXL1, consistently associated with a decrease in PEX risk (OR=0.63, p=6.33x10-31) in nine different ethnic populations. We provide experimental evidence for a functional enhancer-like regulatory activity of the genomic region surrounding rs7173049 influencing expression levels of ISLR2 (immunoglobulin superfamily containing leucine-rich repeat protein 2) and STRA6 (stimulated by retinoic acid receptor 6), apparently mediated by allele-specific binding of the transcription factor THRβ (thyroid hormone receptor beta). We further show that the protective rs7173049-G allele correlates with increased tissue expression levels of ISLR2 and STRA6 and that both genes are significantly downregulated in tissues of PEX patients together with other key components of the STRA6 receptor-driven retinoic acid signaling pathway. siRNA-mediated downregulation of retinoic acid signaling induces upregulation of LOXL1 and PEX-associated matrix genes in PEX-relevant cell types. These data indicate that dysregulation of STRA6 and impaired retinoid metabolismare involved in the pathophysiology of PEX syndrome and that the variant rs7173049-G, which represents the first common variant at the broad LOXL1 locus without allele effect reversal, mediates a protective effect through upregulation of STRA6 in ocular tissues.
Coco G, Amparo F, Patel S, Foulsham W, Carreno-Galeano JT, Stockslager S, Ciolino J, Yin J, Dana R. Oral guaifenesin for treatment of filamentary keratitis: A pilot study. Ocul Surf. 2019;
PURPOSE: Pilot study to evaluate the safety and efficacy of oral guaifenesin in reducing the signs and symptoms of filamentary keratitis. METHODS: Prospective, uncontrolled open-label pilot study. Twelve patients with non-Sjögren dry eye disease (DED) and secondary filamentary keratitis received treatment with oral guaifenesin 600 mg twice a day (total dose of 1.2 g/day) for 4 weeks. Adverse events, change in the number of corneal filaments, corneal fluorescein staining (CFS; NEI grading system), and symptoms (Ocular Surface Disease Index) were assessed. RESULTS: Before starting oral guaifenesin, all patients were on topical medical therapy for their condition. At baseline, the mean number of filaments was 5.8 ± 2.9, CFS score 7.3 ± 3.2, and OSDI score 55.6 ± 25. After 4 weeks of treatment, the number of filaments was 2.1 ± 2.2 (p = 0.04 vs. baseline), CFS score 6.5 ± 3.1 (p = 0.5), and OSDI score 46.1 ± 30.9 (p = 0.2). One patient discontinued the medication due to gastrointestinal side effects. CONCLUSIONS: Oral guaifenesin was safe and generally well tolerated, and demonstrated modest efficacy in reducing the severity of filamentary keratitis. These results should be considered preliminary; however, placebo-controlled investigations would be justified to evaluate the therapeutic efficacy of oral guaifenesin as a mucolytic in treatment of filamentary keratitis.
