RNA sequencing analysis for comparing gene expression of the corneal endothelium of Slc4a11-/- vs Slc4a11+/+ mice
Ontology highlight
ABSTRACT: Purpose: Slc4a11 KO mice show significant edema and altered corneal endothelial morphology at an early age with concomitant increased mitochondrial ROS and oxidative damage relative to wild type. Here we used RNA-Seq with the goal of finding pathways related to corneal endothelial metabolic, pump and barrier function alterations. Methods: Corneal endothelium-Descemet’s membrane (CEDM) samples were from WT and Slc4a11 KO mice at 12 weeks of age. RNA sequencing data was subjected to Ingenuity Pathway Analysis and QPCR for validation. Results: The RNA sequencing IPA analysis predicted activation, inhibition or differential regulation of several pathways. We validated downregulation of Glycolytic enzymes, Mitochondrial complex components and Ion transporters. We observed upregulation of genes of cholesterol biosynthesis, GSH metabolism and tight and adherens junctions. Conclusions: Slc4a11 KO induces a coordinated decrease in glycolysis, glutaminolysis, oxygen consumption, lactate transporters and Na-K-ATPase. These changes together with the altered barrier function cause an accumulation of stromal lactate in Slc4a11 KO mice leading to chronic corneal edema.
Project description:Here, we evaluate the efficacy of cryopreserved human embryonic stem cell (hESC)-derived corneal endothelial cells (CECs) to form a functional monolayer of corneal endothelium (CE) in mammals (rabbits) and non-human primates (monkeys). We injected cryopreserved hESC-derived CECs in rabbits and monkeys either immediately after removing 8 mm of the central portion of the CE or a few days later when corneal edema developed. All clinical models developed deturgesced and clear corneas 2-3 weeks following the CEC injection and remained comparable to the CE of the untreated eye. Confocal scanning microscopy confirmed an intact structure of hexagonal/polygonal cells and immunohistochemical analysis illustrated a monolayer expressing barrier and pump function proteins in the regenerated CE. The necropsy examination confirmed no remarkable change in multiple tissues examined for teratoma formation. In conclusion, our data demonstrate the efficacy of cryopreserved hESC-derived CECs to form a functional CE on the denuded Descemet’s membrane.
Project description:Considerable interest has been generated for the development through cell-tissue engineering of suitable corneal endothelial graft alternatives, which can potentially alleviate the shortage of corneal transplant material. The advent of less invasive suture-less key-hole surgery options such as Descemet’s Stripping Endothelial Keratoplasty (DSEK) and Descemet’s Membrane Endothelial Keratoplasty (DMEK), which involve transplantation of solely the endothelial layer instead of full thickness cornea, provide further impetus for the development of alternative endothelial grafts for clinical applications. A major challenge for this endeavor is the lack of specific markers for this cell type. To identify genes that reliably mark corneal endothelial cells (CECs) in vivo and in vitro, we performed RNA-sequencing on freshly isolated human CECs (from both young and old donors), CEC cultures, and corneal stroma. Gene expression of these corneal cell types were also compared to that of other human tissue types. Based on high throughput comparative gene expression analysis, we identified a panel of markers that are: i) highly expressed in CECs from both young donors and old donors; ii) expressed in CECs in vivo and in vitro; and iii) not expressed in corneal stroma keratocytes and the activated corneal stroma fibroblasts. These were SLC4A11, COL8A2 and CYYR1. The use of this panel of genes in combination reliably ascertains the identity of the CEC cell type.
Project description:Mutations in the solute-linked carrier family 4 member 11 (SLC4A11) gene are associated with several corneal endothelial dystrophies, in all of which visually significant cornea edema may require corneal transplantation. To elucidate the pathogenesis of SLC4A11 associated corneal endothelial dystrophies, we analyzed the transcriptome of immortalized mouse corneal endothelial cells (Slc4a11-/- MCEnC) and Slc4a11+/+ MCEnC as controls.
Project description:This dataset contains proteomic profiles of Descemet's membrane (DM) with corneal endothelial cells derived from patients with Fuchs endothelial corneal dystrophy (FECD) and non-FECD subjects by shotgun proteomics. FECD is the most common inherited corneal disease. Fibrillar focal excrescences, called guttae, and corneal edema due to corneal endothelial cell death result in progressive vision loss. Our dataset indicated that 32 distinctive molecules were expressed only in the FECD-DM but not in the DM of the control subject, possibly having important roles in the pathophysiology of FECD.
Project description:Mutations in the solute-linked carrier family 4 member 11 (SLC4A11) gene are associated with several corneal endothelial dystrophies, in all of which visually significant cornea edema may require corneal transplantation. To elucidate the pathogenesis of SLC4A11 associated corneal endothelial dystrophies, we analyzed the transcriptome of SLC4A11 knock-down primary human corneal endothelium (SLC4A11 KD pHCEnC) and scrambled RNA treated pHCEnC as controls.
Project description:<p>Fuchs' Endothelial Corneal Dystrophy (FECD) is a common disease that results in loss of vision associated with progressive corneal edema and loss of corneal transparency. In the initial stages of the disease, excrescences on Descemet's membrane with the appearance of an abnormal posterior collagenous layer, result in the clinical and pathologic appearance of guttae. Corneal edema ensues as endothelial function is compromised that may result in stromal edema, epithelial edema, and painful bullous keratopathy. Penetrating or endothelial keratoplasty is the only definitive treatment, with palliative care the only option prior to surgery. The pathophysiology underlying FECD, particularly in the common cases that affect older individuals, remains unknown, with a genetic predisposition being reported as the single best predictor of disease.</p> <p>Three independent groups funded by the National Eye Institute (NEI), with well-established programs in the genetics of FECD, conducted a genome-wide association study of FECD. The collaboration comprised investigators from Case Western University (CWRU), Duke University (DUEC), and Johns Hopkins University (JHU). CWRU and DUEC contributed samples that were genotyped at CIDR for the GWAS. Johns Hopkins University (JHU) provided samples for the replication phase of the study, where their data are not listed in dbGaP. Cohorts of FECD cases and controls were assembled. Synchronization of clinical and coded data was performed to unify the information across centers. The family history, clinical, demographic information, and genome-wide genotype data for samples from CWRU and DUEC were deposited in dbGaP.</p>
Project description:Fuchs’ endothelial corneal dystrophy is major corneal disorder in the western world affecting the innermost part of the cornea, which leads to visual impairment. The morphological changes observed in Fuchs’ endothelial corneal dystrophy is well described, however, much less in known of the pathology at the molecular level. As the morphological changes observed in the cornea is profound in the extracellular matrix we sought to determine in protein profiles and changes herein in the Descement’s membrane and endothelium layer of Fuchs’ endothelial conrneal dystrophy patients when compared to healthy control tissue. Using the extracted ion chromatogram label-free MS based quantification method we quantified approximately the 50 most abundant proteins of the Descemet’s membrane and endothelial layer in in patient and control tissue. In addition, using the isobaric tag for relative and absolute quantification MS method resulted in a total of 22 regulated proteins of which the majority were extracellular proteins known to be involved in proper assembly and modulation of the basement membrane in other tissues. Many of the regulated proteins were furthermore among the most abundant proteins quantified. The two MS methods performed here suggest altered arrangement of the extracellular matrix in Fuchs’ endothelial corneal dystrophy and provide new candidate proteins that may be involved in molecular mechanism of this disease.
Project description:The corneal epithelial barrier maintains the metabolic activities of the ocular surface by regulating membrane transporters and metabolic enzymes responsible for the homeostasis of the eye as well as the pharmacokinetic behavior of drugs. Despite its importance, no established biomimetic in vitro methods are available to perform the spatiotemporal investigation of metabolism and determine the transportation of endogenous and exogenous molecules across the corneal epithelium barrier. This study introduces multiple corneal epitheliums on a chip namely, Corneal Epithelium on a Chip (CEpOC), which enables the spatiotemporal collection as well as analysis of micro-scaled extracellular metabolites from both the apical and basolateral sides of the barriers. Longitudinal samples collected during 48 h period were analyzed using untargeted liquid chromatography-mass spectrometry metabolomics method, and 104 metabolites were annotated. We observed the spatiotemporal secretion of biologically relevant metabolites (i.e., antioxidant, glutathione and uric acid) as well as the depletion of essential nutrients such as amino acids and vitamins mimicking the in vivo molecules trafficking across the human corneal epithelium. Through the shifts of extracellular metabolites and quantitative analysis of mRNA associated with transporters, we were able to investigate the secretion and transportation activities across the polarized barrier in a correlation with the expression of corneal transporters. Thus, CEpOC can provide a non-invasive, simple, yet effectively informative method to determine pharmacokinetics and pharmacodynamics as well as to discover novel biomarkers for drug toxicological and safety tests as advanced experimental model of the human corneal epithelium.
Project description:<p>Fuchs' Endothelial Corneal Dystrophy (FECD) is a common disease that results in loss of vision associated with progressive corneal edema and loss of corneal transparency. In the initial stages of the disease, excrescences on Descemet's membrane with the appearance of an abnormal posterior collagenous layer, result in the clinical and pathologic appearance of guttae. Corneal edema ensues as endothelial function is compromised that may result in stromal edema, epithelial edema, and painful bullous keratopathy. Penetrating or endothelial keratoplasty is the only definitive treatment, with palliative care the only option prior to surgery. The pathophysiology underlying FECD, particularly in the common cases that affect older individuals, remains unknown, with a genetic predisposition being reported as the single best predictor of disease.</p> <p>Three independent groups funded by the National Eye Institute (NEI), with well-established programs in the genetics of FECD, conducted a genome-wide association study of FECD. The collaboration comprised investigators from Case Western University (CWRU), Duke University (DUEC), and Johns Hopkins University (JHU). CWRU and DUEC contributed samples that were genotyped at CIDR for the GWAS. Johns Hopkins University (JHU) provided samples for the replication phase of the study, where their data are not listed in dbGaP. Cohorts of FECD cases and controls were assembled. Synchronization of clinical and coded data was performed to unify the information across centers. The family history, clinical, demographic information, and genome-wide genotype data for samples from CWRU and DUEC were deposited in dbGaP.</p>
Project description:The cornea is the transparent tissue covering the anterior part of the eye. Its main roles are to convey the light toward the retina, and to act as a protective barrier against infection or injury for the eye. The transparency of the cornea is a crucial component of its functionality and is the result of specific architecture and cell arrangements. The inner layer of the cornea is the endothelium, composed of a monolayer of endothelial cells. The next layer is the stroma, representing about two third of the thickness of the cornea, and is mainly composed of a specifically arranged extracellular matrix, secreted by few keratocytes1–4. Finally, the external layer is a life-long renewed pluristratified epithelium. The regulated epithelial homeostasis, crucial to maintain the corneal transparency, relies on stem and progenitor cells5. To coordinate epithelial homeostasis and healing, and to adequately respond to any change in the corneal environment, this tissue is highly innervated6,7. The corneal innervation is mainly composed of A and C sensory fibres whose cell bodies are located in the ophthalmic branch of the trigeminal ganglion8. Those fibres penetrate the corneal stroma from the periphery, as bundles of fibres branching and spreading within the stroma9. When entering in the epithelium, the fibres branche again and radiate horizontally to form the subbasal plexus. Finally, the sensory fibres shift orientation to reach the top of the epithelium, where they end up as free nerve endings6,7. There are three classes of fibres innervating the cornea: the mechano-nociceptors, the cold sensing neurons and the polymodal nociceptors, reacting respectively to mechanical, thermal and chemical stimuli10,11. Stimuli transduction is not the only role of the corneal innervation, as these fibres have a crucial role on epithelial homeostasis through the secretion of trophic factors essential for epithelial cell survival12. Due to its localization, the cornea is highly exposed to ultraviolet radiation and high oxygen tension, making it particularly vulnerable to mitochondrial defects13. These defects can be either inherited or non-inherited. Inherited forms result from mutations in mitochondrial DNA (mtDNA) or nuclear gene defects affecting mitochondrial function14. Inherited mitochondrial dysfunction is a key factor in the progression of Fuchs endothelial corneal dystrophy (FECD) and keratoconus13,15,16. Non-inherited mitochondrial dysfunction, on the other hand, can occur due to spontaneous mtDNA mutations or somatic mutations that accumulate with age, rendering the mitochondrial metabolism less efficient with time17. To date, the impact of inherited mitochondrial dysfunctions on corneal epithelium physiology has not been extensively studied. Case reports have linked mitochondrial diseases to corneal cloudiness18,19, perforation20 and edema21. Furthermore, mitochondrial defect was associated to inflammatory context and ROS production in ocular surface pathologies13,22. Despite these studies, the direct effect of mitochondrial disfunction on corneal biology remains elusive. Among the known pathologies originating from an inherited mitochondrial dysfunction, the dominant optic atrophy (DOA) is an inherited blinding disease caused by the degenescence of the retinal cell ganglions forming the optic nerve23. The mutation of the gene OPA1 is responsible for the majority of the DOA diagnostics. OPA1 gene encodes for a mitochondrial protein involved in the fusion process and is essential to maintain the organelle integrity. Generally, optic neuropathy is the characteristic syndrome for DOA, but a subset of patients, called dominant optic atrophy plus (DOA+), also declare extra-ocular syndromes such as ataxia, deafness and peripheral neuropathies24,25. A mouse model, bearing the OPA1delTTAG mutation, recapitulates the degenerative syndromes encountered in DOA+ patients25.. While DOA is associated with lens cloudiness, no report has linked DOA to ocular surface defects. Here, we investigated the impact of OPA1 delTTAG mutation on mouse cornea as its structure includes a large amout of sensory fibres that are crucial to maintain corneal homeostasis.