Limbal and Central Corneal Epithelia
Ontology highlight
ABSTRACT:
ORGANISM(S): Rattus norvegicus
PROVIDER: GSE4121 | GEO | 2006/05/15
SECONDARY ACCESSION(S): PRJNA94917
REPOSITORIES: GEO
Similar Datasets
Project description:Limbal and central regoins of the rat cornea epithelium were used to constract 2 SAGE libraries, in order to identify candidate genes to distinguish stem cell from differentiated central cornea epithelium cells. Keywords: gene expression SAGE-based, count cornea epithelium was scraped from central cornea and limbal Epithelium regions of 6 week male Wister rat 16 and 48 eye (respectively).
2006-05-15 | E-GEOD-4121 | biostudies-arrayexpress
Project description:Comprehensive transcriptome analysis of four distinct human limbal compartments, including basal limbal crypts (BLCs), superficial limbal crypts (SLCs), cornea, and the supporting stroma, with the aid of laser capture microdissection and deep RNA sequencing.
2013-07-01 | E-MTAB-1498 | biostudies-arrayexpress
Project description:Whole human conjunctivae and human corneas were obtained from the National Disease Research Interchange (NDRI, Philadelphia, PA) and processed between 48 - 72 hr of death. No donor details apart from age, sex and cause of death were released. Criteria for inclusion were donor ages between 25 - 65 years old and overt physical integrity of the epithelium over the central cornea as revealed by a quick stain with 0.1 % Trypan blue. For each replicate experiment (Conjunctiva 1 and Cornea 1; Conjunctiva 2 and Cornea 2;Conjunctiva 3 and Cornea 3), RNA from two different corneal or conjunctival specimens was pooled and converted into cDNA. Appropriately fragmented biotin-labeled cRNA was hybridized to the HG-U133A GeneChips® (Affymetrix) oligonucleotide microarray following the manufacture protocol. Three separate experiments each including one conjunctival and one corneal cRNA pool were performed (Conjunctiva 1 and Cornea 1; Conjunctiva 2 and Cornea 2;Conjunctiva 3 and Cornea 3).
2007-11-01 | E-GEOD-5543 | biostudies-arrayexpress
Project description:Corneal epithelial stem cells reside in the limbus that is the transitional zone between the cornea and conjunctiva, and are essential to maintain the homeostasis of corneal epithelium. However, their characterization is poorly understood. Therefore, we constructed gene expression profiles of limbal epithelial SP and non-SP cell using RNA-sequencing. As a result, limbal epithelial SP cells have immature cell phenotypes with endothelial/mesenchymal cell markers, while limbal epithelial non-SP cells have epithelial progenitor cell markers.
2016-04-18 | GSE79620 | GEO
Project description:Transplantation of amniotic membrane-expanded limbal epithelium (AMLE) in place of donor tissue grafts results in significantly improved outcomes for patients suffering from severe limbal stem cell deficiency; however the reasons for such superior results are unclear. The purpose of this study was to identify transcriptional gene profiles specific to AMLE and donor central corneal epithelium (CE), which may contribute to the divergent clinical outcomes observed following transplant. Limbal fibroblasts which underlie the epithelium and secrete extracellular matrix proteins following injury/surgery were also profiled. Using cell culture, immunofluorescence, microarray gene expression profiling and qRT-PCR validation; this study aims to identify enriched biological processes and pathways which characterise AMLE and CE tissues. We hope the study outcomes will shed light onto the factors which contribute to provide the improved clinical outcomes associated with AMLE transplantation. Gene expression profiling of three central corneal buttons, three amniotic membrane-expanded limbal epithelial cultures and three limbal fibroblast cultures
2014-10-02 | E-GEOD-56421 | biostudies-arrayexpress
Project description:Cofactors of LIM domain proteins (CLIM1 and CLIM2) are widely expressed transcriptional cofactors that are recruited to gene regulatory regions by DNA-binding proteins, including LIM domain transcription factors. In the cornea, epithelial specific expression of a dominant negative (DN) CLIM under the Keratin 14 (K14) promoter causes blistering, inflammation, epithelial hyperplasia and neovascularization, followed by epithelial thinning and subsequent epidermal-like differentiation of the cornea epithelium. This phenotype resembles aspects of limbal stem cell deficiency, suggesting that CLIM proteins may be involved in regulating cornea stem cell maintenance. Consistent with this notion, the K14-DN-Clim cornea epithelium has fewer progenitor cells, and altered proliferation dynamics during epithelial development. Differentially regulated genes in DN-CLIM corneas include those in pathways crucial for stem cell maintenance and regulation of proliferation. In vivo ChIP-Seq experiments in the cornea epithelium show that CLIM associates with DNA regulatory elements containing binding sites for HLH and other non-LIM homeodomain factors, and that many genes that are highly expressed in the limbal epithelium, as well as genes with known roles in stem cell maintenance, are directly regulated by CLIM cofactors. DN-CLIM decreases the expression of Wnt inhibitors, including the direct target Wnt5a, causing increased Wnt signaling in the limbal region of DN-CLIM corneas. Together our results indicate that CLIMs regulate cornea stem cell maintenance by controlling Wnt activity and suggest the possibility that this pathway may be altered in limbal stem cell deficiency.
2016-04-28 | GSE59205 | GEO
Project description:Limbal epithelial stem cells (LESCs) reside within the LSC niche (LSCN), located at the annular transition zone between the cornea and conjunctiva. LESCs are important for the long-term maintenance of the corneal epithelium and critical for repopulating the corneal epithelium after injury. We have recently identified that a hyaluronan (HA)-rich extracellular matrix (ECM) exists within the LSCN, and that this HA matrix is necessary for maintaining LESCs in the “stem cell” state. Herein we further characterized the composition of the LSCN, identifying key components of the HA-rich matrix. We identified that the hyaladherins IαI, TSG-6 and versican are highly expressed in the limbus when compared to the cornea. For IαI, Heavy chain 5 (HC5) was found to be the most highly expressed HC in the mouse and human cornea, and associates with HA forming HA/HC5 specific matrices. CD44 is the most likely receptor that mediates the interaction between LESCs and the HA-specific matrix. The LSCN is composed of a rich HA matrix that contains HA/HC5. HA/HC5 complexes could be used as an improved substrate for culturing LESCs during ex vivo expansion for limbal stem cell transplantation.
2023-11-08 | GSE244412 | GEO
Project description:To date, there is no specific marker for limbal epithelial stem cells. The identification of a marker that is expressed in the limbal epithelium but not in the cornea or conjunctiva epithelium has been a growing need. To search for limbal-specific marker(s), we performed preferential gene profiling in the limbus in direct comparison to that in the cornea and conjunctiva using microarray technique. This study consisted of gene expression profiles comparing the limbus to the cornea and conjunctiva.
2013-01-01 | E-GEOD-38190 | biostudies-arrayexpress
Project description:Limbal stem cells (LSCs), known as corneal epithelial stem cells, are located at the basal epithelial layer of the corneal limbus and serve an important function in maintaining the homeostasis of the corneal epithelium. Several putative molecular markers of LSCs have been previously identified. However, the specificity of these markers remains largely controversial. To address this gap in the current understanding of LSCs, we performed a transcriptome profiling of heterogeneous corneal limbal basal cells using single-cell transcriptomics technology to identify LSCs and their exclusive markers. We isolated limbal basal cells from two young donors, constructed scRNA-seq libraries, generated RNA-sequencing data using the 10x Genomics platform, and then finally obtained the transcriptome of about 18,000 individual single-cells using Cell ranger (https://10xgenomics.com). Next, we performed quality control, filtering and data integration using Seurat package (https://satijalab.org/seurat), about 16,400 cells were retained for further downstream analysis such as dimensional reduction, unsupervised clustering, and Differentially expressed gene selection, trajectory analysis and visualization. We identified 11 unique clusters of cells assigned to a putative cell type based on published known biomarkers for differentiation, proliferation and putative epithelial stem cells. As a results, we found 2 Terminally Differentiated Cell (TDC), 3 Post-Mitotic Cell (PMC), 1 Transient Amplifying Cell (TAC), 2 Limbal Progenitor Cell (LPC), Putative Limbal Stem Cell (LSC) and 2 Melanocyte (MC) sub-cell type clusters. Furthermore, we confirmed the trajectory order of LSC differentiation for 9 clusters using Pseudotemporal and Functional PCA analysis. Lastly, we validated each assigned cell subtypes and determined their location in human corneal limbus tissue with 9 markers using RNAscope We were able to reveal the heterogeneity of corneal limbal basal epithelium by defining novel dynamic trajectories for cell types in a pseudotemporal manner. This approach allowed us to identify the distinct clusters of LSCs and progenitors with exclusively expressed markers, and might apply for translational research on regenerating a normal corneal epithelium and restoring vision.
2021-01-14 | GSE153515 | GEO
Project description:Limbal epithelial stem cell (LESC) deficiency represents a significant clinical problem especially in bilateral cases. Induced pluripotent stem cells (iPSC) may be a promising source of LESC, allowing standardized and continual propagation and banking. The objective of this study was to generate iPSC from human limbal epithelial cultures and differentiate them back into limbal epithelial cells using substrata mimicking the natural LESC niche. Using Yamanaka’s episomal vectors limbal-derived iPSC were reprogrammed from LESC cultured from donor corneoscleral rims and from human skin fibroblasts. A clone from limbal-derived iPSC expressed stemness markers, had a diploid karyotype, and produced teratomas in nude mice representing three germ layers. Compared to parental LESC, this clone had fewer specific gene methylation changes revealed using the Illumina Infinium Methylation 450k Beadchips than compared to skin fibroblasts. The expression of putative LESC markers was examined by quantitative RT-PCR and immunostaining in limbal-derived and fibroblast-derived iPSC cultured on denuded human amniotic membrane or denuded cornea. Limbal-derived iPSC had markedly stronger expression of PAX6, ABCG2, Np63, keratins 14, 15, 17, and N-cadherin than fibroblast-derived iPSC. On denuded corneas, limbal-derived iPSC showed the expression of differentiated corneal keratins 3 and 12. The data suggest that iPSC differentiation to a desired lineage may be facilitated by their generation from the same tissue. This may be related to preservation of parental tissue epigenetic methylation signatures in iPSC and use of biological substrata similar to the natural niche of parental cells. The data pave the way for generating transplantable LESC from limbal-derived iPSC. Bisulphite converted DNA from the 12 samples were hybridised to the Illumina Infinium 450k Human Methylation Beadchip
2014-06-30 | E-GEOD-53918 | biostudies-arrayexpress