Project description:Consistent with clinical observations that posterior uveitis frequently involves the retinal vasculature and recent recognition of vascular heterogeneity, we hypothesized that retinal vascular endothelium was a cell population of unique molecular phenotype. Donor-matched cultures of primary retinal and choroidal endothelial cells from 6 human cadavers were incubated with either Toxoplasma gondii tachyzoites (10:1, parasite:cell) or Escherichia coli lipopolysaccharide (100 ng/mL); control cultures were simultaneously incubated with medium. Gene expression profiling of endothelial cells was performed using oligonucleotide arrays containing probes designed to detect 8747 human transcripts. After normalization, differential gene expression was assessed by the significance analysis of microarrays, with the false discovery rate set at 5 %. For selected genes, differences in level of expression between retinal and choroidal cells were evaluated by real-time RT-PCR. Graphical descriptive analysis demonstrated strong correlation between gene expression of unstimulated retinal and choroidal endothelial cells, but also highlighted distinctly different patterns of expression that were greater than differences noted between donors or between unstimulated and stimulated cells. Overall, 779 of 8,747 transcripts (8.9 %) were differentially represented. Notably, the 330 transcripts that were present at higher levels in retinal cells included a larger percentage of transcripts encoding molecules involved in the immune response. Differential gene expression was confirmed for 12 transcripts by RT-PCR. Retinal and choroidal vascular endothelial cells display distinctive gene expression profiles. Our findings suggest the possibility of treating posterior uveitis by targeting specific interactions between the retinal endothelial cell and an infiltrating leukocyte. Experiment Overall Design: Retinal and choroidal vascular endothelial cells were isolated from both eyes of 6 human cadaver donors. Endothelial cells of each subtype from each donor were separately pooled and cultured. In a first series of experiments (Experiment 1), donor-matched cultures of retinal and choroidal endothelial cells derived from 3 donors were incubated with either T. gondii tachyzoites or medium alone. In a second set of experiments (Experiment 2), cultured retinal and choroidal endothelial cells derived from the other 3 donors were stimulated with LPS or medium alone. Whenever possible, 2 replicate dishes of endothelial cells were subjected to each set of conditions. Subsequent to incubations, mRNA was extracted from a cell lysate prepared from each dish of cells, and cRNA derived from each mRNA preparation was separately hybridized to one oligonucleotide expression array.
Project description:Consistent with clinical observations that posterior uveitis frequently involves the retinal vasculature and recent recognition of vascular heterogeneity, we hypothesized that retinal vascular endothelium was a cell population of unique molecular phenotype. Donor-matched cultures of primary retinal and choroidal endothelial cells from 6 human cadavers were incubated with either Toxoplasma gondii tachyzoites (10:1, parasite:cell) or Escherichia coli lipopolysaccharide (100 ng/mL); control cultures were simultaneously incubated with medium. Gene expression profiling of endothelial cells was performed using oligonucleotide arrays containing probes designed to detect 8747 human transcripts. After normalization, differential gene expression was assessed by the significance analysis of microarrays, with the false discovery rate set at 5 %. For selected genes, differences in level of expression between retinal and choroidal cells were evaluated by real-time RT-PCR. Graphical descriptive analysis demonstrated strong correlation between gene expression of unstimulated retinal and choroidal endothelial cells, but also highlighted distinctly different patterns of expression that were greater than differences noted between donors or between unstimulated and stimulated cells. Overall, 779 of 8,747 transcripts (8.9 %) were differentially represented. Notably, the 330 transcripts that were present at higher levels in retinal cells included a larger percentage of transcripts encoding molecules involved in the immune response. Differential gene expression was confirmed for 12 transcripts by RT-PCR. Retinal and choroidal vascular endothelial cells display distinctive gene expression profiles. Our findings suggest the possibility of treating posterior uveitis by targeting specific interactions between the retinal endothelial cell and an infiltrating leukocyte. Keywords: Cell type comparison, stress response
Project description:PURPOSE Diseases that involve choroidal or retinal endothelial vascular cells are leading causes of vision loss: age-related macular degeneration, retinal ischemic vasculopathies and non-infectious posterior uveitis. Proteins differentially expressed by these endothelial cell populations are potential drug targets. We used deep proteomics to define the molecular phenotype of human choroidal and retinal endothelial cells at the protein level. METHODS Choroidal and retinal endothelial cells were separately isolated from 5 human eye pairs by selection on CD31. Total protein was extracted and digested, and peptide fractions were analysed by reverse-phase liquid chromatography tandem mass spectrometry. Peptide sequences were assigned to fragment ion spectra and proteins were inferred using public protein databases. Protein abundance was determined by spectral counting. Protein expression in choroidal versus retinal endothelial cells was compared using edgeR package in R, and annotation enrichment analysis was performed. RESULTS Human choroidal or retinal endothelial cells expressed 5042 non-redundant proteins. Setting the false discovery rate at 5%, 498 proteins (14.4%) of 3454 quantifiable proteins with minimum mean spectral counts of 2.5 were differentially expressed between cell populations. Choroidal and retinal endothelial cells were enriched in angiogenic proteins, and retinal endothelial cells were also enriched in immunologic proteins. CONCLUSIONS This work demonstrates the protein heterogeneity of human choroidal and retinal vascular endothelial cells and provides multiple candidates for further study as novel treatments or drug targets for posterior eye diseases.
Project description:To compare the gene expression profiles of unpassaged, proliferating HUVEC and human iris, retinal and choroidal microvascular endothelial cells. Gene expression profiling revealed significant differences between HUVEC and ocular microvascular endothelial cells suggesting that HUVE cells may not be a suitable surrogate when studying pathophysiological mechanisms of ocular disorders. There were significant differences in the gene expression of important cell signalling pathways in human retinal and choroidal ECs. These differences may be important in the mechanisms and treatment of choroidal and retinal neovascularisation. 12 arrays are included. Endothelial cells were derived from 4 tissues: iris, retina, choroid and human umbilical vein. RNA extracts from cells were hybridised to Affymetrix HGU133plus2 arrays in triplicate.
Project description:To compare the gene expression profiles of unpassaged, proliferating HUVEC and human iris, retinal and choroidal microvascular endothelial cells. Gene expression profiling revealed significant differences between HUVEC and ocular microvascular endothelial cells suggesting that HUVE cells may not be a suitable surrogate when studying pathophysiological mechanisms of ocular disorders. There were significant differences in the gene expression of important cell signalling pathways in human retinal and choroidal ECs. These differences may be important in the mechanisms and treatment of choroidal and retinal neovascularisation.
Project description:Dysfunction of the blood retinal barriers and/or proliferation of retinal and choroidal endothelial cells are caused by late stages of diabetic retinopathy (DR) and neovascular age-related macular degeneration (nAMD). To elucidate endothelial-derived pathomechanisms in DR and nAMD, we established immortalized mouse cell lines of retinal (REC), choroidal (ChEC) and brain (BEC)endothelial cells. We compared the functional and transcriptomic state of these cells depending on their tissue origin. Intriguingly, activation of the wingless-type MMTV integration site (Wnt)/β-catenin signaling pathway restored barrier properties in BEC and REC, but increased permeability of ChEC. Transcriptome profiling showed that the immune system and pathways such as hypoxia-inducible factor (HIF) 1/2α-, transforming growth factor (TGF) β- and vascular endothelial growth factor (VEGF) were differentially regulated among endothelial cells. These findings significantly increase the understanding of the vascular biology of endothelial cells, highlighting the fact that depending on their tissue origin, their contribution to vascular pathologies such as DR or nAMD may vary.
Project description:To investigate the differences in gene expression between matched human macular and peripheral choroidal endothelial cells (CEC) and matched human macular inner and outer CEC. The gene expression profiles of the unpassaged cell types were compared using Affymetrix GeneChip arrays.
Project description:Retinal pigment epithelial (RPE) cells and choroidal stromal fibroblast (CSF) were isolated from healthy human donor eyes. Cells were cultured and RNA extracted.
Project description:Vascular endothelial growth factor (VEGF) is a key driver of retinal and choroidal angiogenesis in wet age-related macular degeneration (nAMD). The present study investigated the impact of dimethyl fumarate (DMFu), a novel nAMD therapeutic candidate, on the transcriptomic profile of VEGF-treated primary human retinal endothelial cells (HRECs). In performing this study, we have described the individual transcriptomic implications of VEGF and DMFu in HRECs and characterised the impact of DMFu treatment on gene expression in VEGF-activated HRECs.
Project description:The activity and survival of retinal photoreceptors depend on support functions performed by the retinal pigment epithelium (RPE) and on oxygen and nutrients delivered by blood vessels in the underlying choroid. By combining single cell and bulk RNA sequencing, we categorized mouse RPE/choroid cell types and characterized the tissue-specific transcriptomic features of choroidal endothelial cells. We found that choroidal endothelium adjacent to the RPE expresses high levels of Indian Hedgehog, and identified its downstream target as stromal GLI1+ mesenchymal stem cell-like cells. Genetic impairment of Hedgehog signaling in vivo induced significant loss of choroidal mast cells, as well as an altered inflammatory response and exacerbated visual function defects after retinal damage. Our studies reveal the cellular and molecular landscape of adult RPE/choroid and uncover a Hedgehog-regulated choroidal immunomodulatory signaling circuit. These results open new avenues for the study and treatment of retinal vascular diseases and choroid-related inflammatory blinding disorders.