Project description:Corneal organoids are useful tools for disease modeling and tissue transplantation however they have not yet been well studied during maturation. We characterized human iPSC derived corneal organoids at 1, 2, 3 and 4 months of development using single-cell RNA sequencing to determine the cellular heterogeneity at each stage. We found pluripotent cell clusters committed to epithelial cell lineage at 1 month early corneal epithelial, endothelial and stromal cells markers at 2 months, keratocytes as the largest cell population at 3 months, and a large epithelial cell population at 4 months. We compared organoid to fetal corneal development at different stages and found that 4 month organoids closely resemble the corneal cellular complexity of the fetal (16 post conception week) and adult cornea. Using RNA velocity pseudotime trajectory analysis, we found that eye field primordial cells and limbal stem cells appear to give rise to corneal epithelial cells during development.
Project description:The cornea is a protective and refractive barrier in the eye crucial for vision. Understanding the human cornea in health, disease and cell-based treatments can be greatly advanced with cornea organoids developed in culture from induced pluripotent stem cells. While a limited number of studies have investigated the single-cell transcriptomic composition of the human cornea, its organoids have not been examined similarly. Here we elucidated the transcriptomic cell fate map of 4-month-old human cornea organoids and human donor corneas. The organoids harbor cell clusters that resemble cells of the corneal epithelium, stroma and endothelium with sub-populations that capture signatures of early developmental states. Unlike the adult cornea where the largest cell population is stromal, the organoids contain large proportions of epithelial and endothelial-like cells. These corneal organoids offer a three-dimensional model to study corneal diseases and integrated responses of different cell types.
Project description:Dr. Panjwani's laboratory is focusing on the mechanism by which galectins-3 and 7 mediate corneal epithelial cell migration. We are currently performing studies to: (i) identify and characterize the corneal epithelial cell surface and extracellular matrix (ECM) molecules which serve as counterreceptors of galectin-3 and -7, to establish whether the lectins modulate corneal epithelial cell migration by binding to well known integrins, growth factor receptors, and/or ECM molecules and (ii) determine whether galectin-3 mediates corneal epithelial cell migration indirectly by modulating the expression of key adhesion and/or signal transduction molecules by using small interfering RNA, cDNA microarrays and glycogene arrays. We have prepared three independent preparations of total RNA of corneal epithelial cells from WT mice (total six samples) for analysis of glycogene expression. Samples are Normal Cornea (Left eye) and Laser ablation + 16-18 hours healing (right eye)
Project description:In the present study, we investigated the molecular mechanisms by which Wnk contributes to human corneal epithelial wound healing. To better understand the process, we cultivated human corneal epithelial cells without or with Wnk inhibitor. Using gene profiling, we compared the mRNA profiles of passage 3 human corneal epithelial cells cultivated without Wnk inhibitor with passage 3 human corneal epithelial cells cultivated with Wnk inhibitor. Human corneal epithelial cells are isolated from eye bank donor corneas.
Project description:Mycotic leratitis is the corneal inflammation predominantly caused by Fusarium and Aspergillus species. Corneal epithelium is the earliest cell type encounter the invading pathogen. The innate immune responses of human corneal epithelial cells against Aspergillus flavus is not known. Here we studied the role of human corneal epithelial cells against Aspergillus flavus infection. The results showed that corneal epithelial cells internalized Aspergillus flavus conidia through actin mediated polymerization surrounding the conidia. Further the actin inhibitor cytochalasin D treatment reduced the formation actin ring around the conidia. The engulfed conidia acquired endosomal proteins as revealed by immunofluorescence analsyisis. Mass spectromtery of phagosomal proteins confirmed the recruitment of endosomal proteins and other proteins involved in phagocytosis. These results show the involvement of corneal epithelial cells in anti fungal defense.
Project description:Dr. Panjwani's laboratory is focusing on the mechanism by which galectins-3 and 7 mediate corneal epithelial cell migration. We are currently performing studies to: (i) identify and characterize the corneal epithelial cell surface and extracellular matrix (ECM) molecules which serve as counterreceptors of galectin-3 and -7, to establish whether the lectins modulate corneal epithelial cell migration by binding to well known integrins, growth factor receptors, and/or ECM molecules and (ii) determine whether galectin-3 mediates corneal epithelial cell migration indirectly by modulating the expression of key adhesion and/or signal transduction molecules by using small interfering RNA, cDNA microarrays and glycogene arrays.
Project description:Dr. Panjwani's laboratory is focusing on the mechanism by which galectins-3 and 7 mediate corneal epithelial cell migration. We are currently performing studies to: (i) identify and characterize the corneal epithelial cell surface and extracellular matrix (ECM) molecules which serve as counterreceptors of galectin-3 and -7, to establish whether the lectins modulate corneal epithelial cell migration by binding to well known integrins, growth factor receptors, and/or ECM molecules and (ii) determine whether galectin-3 mediates corneal epithelial cell migration indirectly by modulating the expression of key adhesion and/or signal transduction molecules by using small interfering RNA, cDNA microarrays and glycogene arrays.
Project description:We successfully induced corneal epithelial cells from human iPSCs. Then, we perfomed global expression analysis using microarray to compare the character of hiPSC-derived corneal epithelial cells with that of the other kinds of cells. Total RNA was obtained from human iPSCs (hiPSCs), human iPSC-derived corneal epithelial cells (hiCECs), human corneal limbal epithelial cells (HCECs), human oral keratinocytes (HOKs), human dermal fibroblasts (HDFs) and six weeks-differentiated hiPSCs (hiPSC-derived ocular surface ectoderm, OSE) using the QIAZol reagent. A microarray analysis using Sure Print G3 human 8x60K slides (Agilent technologies) was performed at Takara Bio (Shiga, Japan).
Project description:Adult stem cell identity, plasticity, and homeostasis are precisely orchestrated by lineage-restricted epigenetic and transcriptional regulatory networks. Here, by integrating super-enhancer and chromatin accessibility landscapes, we delineate core transcription regulatory circuitries (CRCs) of limbal stem/progenitor cells (LSCs) and find that RUNX1 and SMAD3 are required for maintenance of the corneal epithelial identity and homeostasis. RUNX1 or SMAD3 depletion inhibits PAX6 and induces LSCs to differentiate into epidermal-like type. RUNX1, PAX6 and SMAD3 (RPS) interact with each other and synergistically establish a CRC to govern the lineage-specific cis-regulatory atlas. Moreover, RUNX1 shapes LSC chromatin architecture via modulating H3K27ac deposition. Disturbance of RPS cooperation results in cell identity switching and dysfunction of the corneal epithelium, which is strongly linked to various human corneal diseases. Our work highlights CRC TF cooperativity for the establishment of stem cell identity and lineage commitment, and provides comprehensive regulatory principles for human stratified epithelial homeostasis and pathogenesis.
Project description:Genome-wide analysis of dihydrotestosterone (DHT) induced changes in gene expression in primary and immortalized human corneal epithelial cells. Analysis of regulation of primary and immortalized human corneal epithelial cells by dihydrotestosterone at gene expression level. The hypothesis tested in the present study was that the androgen-eye interaction in ocular surface epithelial cells like corneal cells is influenced by androgens through regulation of the expression of multiple genes. Results provide important information of the differential regulation and comparitive analysis of numerous genes in response to dihydrotestosterone incubation in primary and immortalized human corneal epithelial cells. Total RNA was obtained from primary and immortalized human corneal epithelial cells treated for 5 days with 10 nM dihydrotestosterone (n=3) or vehicle (n=3). The RNA was then used with Illumina HumanHT-12 v3 Expression BeadChips to determine the effect of DHT on gene expression in the primary human corneal cells grown in our laboratory and the immortalized human corneal epithelial cell line developed in Dr. Rheinwald's laboratory [Rheinwald et al. MCB, 22 (14): 5157. (2002)] and charecterized in Dr. Ilene Gibson's laboratory [Gipson et al. IOVS, 44 (6): 2496. (2003)].