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.
2014-05-27 | PXD000746 | Pride
Project description:Corneal endothelium transcriptome profiling of patients with Fuchs endothelial corneal dystrophy
Project description:Fuchs endothelial corneal dystrophy (FECD) is a vision impairing pathology affecting the endothelial cells of the cornea. To better understand the disease, we developed a method to cultivate FECD cells isolated from surgical specimens. Using gene profiling, we compared the mRNA profiles of passage 2 FECD cells with passage 2 non-pathological corneal endothelial cells isolated from eye bank donor corneas.
Project description:A missense mutation of collagen type VIII alpha 2 chain (COL8A2) gene leads to early onset Fuchs’ endothelial corneal dystrophy (FECD), which can cause blindness through progressive loss of corneal endothelial cells. We established a novel procedure for achieving structural and functional rescue of the post-mitotic corneal endothelium without surgery, using CRISPR/Cas9-based postnatal gene editing in a mouse model of FECD. A single intraocular injection of an adenovirus encoding both the Cas9 gene and guide RNA (Ad-Cas9-Col8a2gRNA) at a titer below the cytotoxic threshold, efficiently knocked down COL8A2 protein expression in corneal endothelial cells, prevented endothelial cell loss, and rescued corneal endothelium pumping function in adult Col8a2 mutant mice. Here, to determine the indel rate in mouse corneal endothelium, we performed deep sequencing of PCR products (including the target site) amplified from genomic DNA of corneal endothelium. We found that the indel rate was 23.7 ± 4.5% in mouse corneal endothelium. Most insertions were 1bp insertions (19.8 ± 4.0% in total reads), while 2bp deletions were the most frequent (1.0 ± 0.3% in total reads). We moreover found that A or T insertion was predominant, with the proportion of A:T:G:C being 48.7 : 44.6 : 1.8 : 4.9.
Project description:A missense mutation of collagen type VIII alpha 2 chain (COL8A2) gene leads to early onset Fuchs’ endothelial corneal dystrophy (FECD), which can cause blindness through progressive loss of corneal endothelial cells. We established a novel procedure for achieving structural and functional rescue of the post-mitotic corneal endothelium without surgery, using CRISPR/Cas9-based postnatal gene editing in a mouse model of FECD. A single intraocular injection of an adenovirus encoding both the Cas9 gene and guide RNA (Ad-Cas9-Col8a2gRNA) at a titer below the cytotoxic threshold, efficiently knocked down COL8A2 protein expression in corneal endothelial cells, prevented endothelial cell loss, and rescued corneal endothelium pumping function in adult Col8a2 mutant mice. Here, we evaluated the off-target activity of humanized gRNA targeting COL8A2 gene by a modified digenome analysis (Nat Methods 12, 237-243). Briefly, in vitro SpCas9 digested genomic DNA with/without gRNA are compared by deep sequencing. The target sequence is CGTCCACGGACGCCATGCT. In this study, we identified 13 candidate sites with homology to the gRNA and 8 candidate sites without homology to the gRNA.
Project description:PURPOSE: To compare the gene expression profiles of normal human corneal endothelium with Fuchs' corneal endothelium, by using serial analysis of gene expression (SAGE). METHODS: Three pairs of normal human corneas were obtained from eye banks. Thirteen bisected Fuchs' corneal buttons were processed at the time of corneal transplantation. The endothelia of normal and Fuchs'-affected corneas were stripped, and total RNA was isolated. Serial analysis of gene expression (SAGE) was performed to identify and quantify gene transcripts. Genes over- and underexpressed by Fuchs' endothelium were limited to P < 0.01 by the method of Audic and Claverie. RESULTS: A total of 19,136 tags were identified with 9,530 from normal and 9,606 from Fuchs' endothelium. The expression of 18 transcripts was upregulated, and 36 transcripts were downregulated in Fuchs' endothelium compared with normal tissue. Upregulated transcripts included serum amyloid A1 and A2, metallothionein, and apolipoprotein D. Of the downregulated transcripts, 26 matched known genes, 3 matched expressed sequence tags (ESTs), and 7 were unknown to current databases. One downregulated transcript involved a newly reported bicarbonate transporter. Decreased transcripts related to antioxidants and proteins conferring protection against toxic stress were noted in Fuchs' versus normal endothelium including nuclear ferritin, glutathione S-transferase-pi, and heat shock 70-kDa protein. Nine different SAGE tags matching mitochondrial sequences accounted for 25% of the ESTs that were decreased in Fuchs' endothelium. CONCLUSIONS: SAGE analysis comparing normal to Fuchs' endothelium demonstrates diminished expression of mitochondrial, pump function, and antiapoptotic cell defense genes. A complete report of gene expression profiles of normal human corneal endothelium can be found in PMID 12583793. Keywords: other