Project description:Purpose: PDGF-D is a potent angiogenic and immune-related factor. It has been demonstrated that PDGF-D play roles in the pathological process of ocular angiogenesis and degenerative diseases. In our previous study, we established a retinal pigment epithelial (RPE) cell-specifc AAV-PDGF-D/GFP mouse model to study PDGF-D's role in age-related macular degeneration (AMD). In this study, we utilized the single-cell transcriptiome seqeuncing technique to explore the cell types of immune cells attracted by PDGF-D overepxression using the same animal models, with emphases on the impact of PDGF-D overexpression on individual cell's behaviour.
Project description:Heterogeneous degeneration of retinal pigment epithelium (RPE) leads to irreversible blindness in diseases associated with macular atrophy. However, the underlying mechanisms of regional RPE degeneration remain poorly understood. To address this gap, this study first identifies a novel RPE subpopulation through the spatial, transcriptomic, and functional analyses, thereby contributing to the understanding of the heterogeneity of degenerative RPE cells. Specifically, omics analyses in human and macaque RPE reveal a peripheral RPE cell population with high SERPINE3 expression, while SERPINE3-GFP knock-in mice show comparable expression patterns. In addition, SMART-seq2 analysis further distinguishes transcriptomic profiles between GFP-positive and GFP-negative RPE cells. Under oxidative stress, SERPINE3 expression increases, and GFP-positive cells exhibit improved survival and reentry into the cell cycle. Notably, genetic studies indicate that SERPINE3 is essential for the oxidative stress resistance of GFP-positive cells. Moreover, loss of SERPINE3 results in regional RPE degeneration and increased microglial accumulation in aged mice. Mechanistically, proteinase screening and co-immunoprecipitation indicate that SERPINE3 targets Caspase-1. Importantly, delivery of SERPINE3 via AAV-Serpine3 prevents RPE degeneration in a geographic atrophy disease model. These findings advance the understanding of RPE heterogeneous degeneration and highlight SERPINE3 as a novel protective factor with therapeutic potential for macular atrophy.
Project description:Heterogeneous degeneration of retinal pigment epithelium (RPE) leads to irreversible blindness in diseases associated with macular atrophy. However, the underlying mechanisms of regional RPE degeneration remain poorly understood. To address this gap, this study first identifies a novel RPE subpopulation through the spatial, transcriptomic, and functional analyses, thereby contributing to the understanding of the heterogeneity of degenerative RPE cells. Specifically, omics analyses in human and macaque RPE reveal a peripheral RPE cell population with high SERPINE3 expression, while SERPINE3-GFP knock-in mice show comparable expression patterns. In addition, SMART-seq2 analysis further distinguishes transcriptomic profiles between GFP-positive and GFP-negative RPE cells. Under oxidative stress, SERPINE3 expression increases, and GFP-positive cells exhibit improved survival and reentry into the cell cycle. Notably, genetic studies indicate that SERPINE3 is essential for the oxidative stress resistance of GFP-positive cells. Moreover, loss of SERPINE3 results in regional RPE degeneration and increased microglial accumulation in aged mice. Mechanistically, proteinase screening and co-immunoprecipitation indicate that SERPINE3 targets Caspase-1. Importantly, delivery of SERPINE3 via AAV-Serpine3 prevents RPE degeneration in a geographic atrophy disease model. These findings advance the understanding of RPE heterogeneous degeneration and highlight SERPINE3 as a novel protective factor with therapeutic potential for macular atrophy.
Project description:Heterogeneous degeneration of retinal pigment epithelium (RPE) leads to irreversible blindness in diseases associated with macular atrophy. However, the underlying mechanisms of regional RPE degeneration remain poorly understood. To address this gap, this study first identifies a novel RPE subpopulation through the spatial, transcriptomic, and functional analyses, thereby contributing to the understanding of the heterogeneity of degenerative RPE cells. Specifically, omics analyses in human and macaque RPE reveal a peripheral RPE cell population with high SERPINE3 expression, while SERPINE3-GFP knock-in mice show comparable expression patterns. In addition, SMART-seq2 analysis further distinguishes transcriptomic profiles between GFP-positive and GFP-negative RPE cells. Under oxidative stress, SERPINE3 expression increases, and GFP-positive cells exhibit improved survival and reentry into the cell cycle. Notably, genetic studies indicate that SERPINE3 is essential for the oxidative stress resistance of GFP-positive cells. Moreover, loss of SERPINE3 results in regional RPE degeneration and increased microglial accumulation in aged mice. Mechanistically, proteinase screening and co-immunoprecipitation indicate that SERPINE3 targets Caspase-1. Importantly, delivery of SERPINE3 via AAV-Serpine3 prevents RPE degeneration in a geographic atrophy disease model. These findings advance the understanding of RPE heterogeneous degeneration and highlight SERPINE3 as a novel protective factor with therapeutic potential for macular atrophy.
Project description:We present a joint scRNA-seq and scATAC-seq atlas of adult human retinal pigment epithelium (RPE) and choroid. We integrate this atlas with a HiChIP enhancer connectome to predict noncoding variants with causal roles in age-related macular degeneration (AMD).
Project description:Wet age-related macular degeneration (AMD) is a progressive degenerative disease and a leading cause of blindness in elderly population. AMD pathogenesis initiated by several signals generates cellular and molecular cross-talk, including complement pathway-mediated inflammation, macrophage activation, and upregulation of angiogenic and cytokine/chemokine pathways. However, the mechanism by which the complement system is activated in AMD is not well understood, although its components are found in the neovascular lesions of wet AMD patients. Here, we show that increased PDGF-D expression engaged both classical and alternative complement pathways and markedly increased chemokine and cytokine responses to activate macrophages, thereby triggering neuroinflammatory milieu and exacerbating pathological neovascularization. Pharmacological targeting of the complement C3a receptor using SB290157 alleviated neuroinflammation by blocking macrophage polarization and by inhibiting pathological choroidal neovascularization (CNV). Our study thus suggests that therapeutic strategies targeting both PDGF-D and complement-mediated inflammatory signals may open up new possibilities for the treatment of neovascular diseases.
Project description:High-throughput sequencing of murine retina and RPE/Choroid (eye cup) tissue following mueller-cell mediated expression of either hVEGFA, hTNFa, or hIl6 by adeno-associated viruses (AAV)