Project description:In the context of human disease, the mechanisms whereby transcription factors reprogram gene expression in reparative responses to injury are not well understood. We have studied the mechanisms of transcriptional reprogramming in disease using murine kidney podocytes as a model for tissue injury. Podocytes are a crucial component of glomeruli, the filtration units of each nephron. Podocyte injury is the initial event in many processes that lead to End Stage Kidney Disease. FOXC2 is a transcription factor known to regulate gene expression in podocytes. FOXC2 and WT1 are both required for podocyte differentiation. Using murine models and human kidney organoids, we investigated FOXC2-mediated transcriptional reprogramming during the course of podocyte injury. Correlating FOXC2 and WT1 ChIP-seq analyses demonstrated that they co-bind many genes expressed in podocytes. Reprogramming the transcriptome involved highly dynamic changes in the binding of FOXC2 and WT1 to target genes during a reparative injury response.
Project description:Podocytes are the highly specialised cells within the glomeruli of the kidney that maintain the filtration barrier by forming interdigitating foot processes and slit-diaphragms. Disruption to these features result in proteinuria. Studies into podocyte biology and disease has been hampered by a paucity of in vitro models of this non-proliferative cell type. Here we characterise sieved glomeruli from kidney organoids derived from human pluripotent stem cells. Compared to conditionally immortalised podocytes, organoid-derived glomeruli show superior podocyte-specific gene and protein expression, morphology and functional properties. Using CRISPR-derived MAFB reporter iPSC lines, homozygous MAFB mutant organoids recapitulated the anticipated disease related transcriptional changes. Culture of kidney organoids on chicken chorioallantoic membrane resulted in glomerular vascularisation, glomerular filtration barrier assembly, formation of slit diaphragms and fenestrated endothelial cells. This definitively demonstrates that human iPSC kidney organoid-derived glomeruli can serve as an accurate model of human podocytopathies and glomerular disease in vitro.
Project description:Hepatocyte nuclear factor 1B (HNF1B) encodes a transcription factor expressed in developing human kidney epithelia. Heterozygous HNF1B mutations are the commonest monogenic cause of dysplastic kidney malformations (DKMs). To understand their pathobiology, we generated heterozygous HNF1B mutant kidney organoids from CRISPR-Cas9 gene-edited human ESCs and iPSCs reprogrammed from a family with HNF1B-asscociated DKMs. Mutant organoids contained enlarged malformed tubules and displayed deregulated cell turnover. This submission is RNAseq of organoids from MAN13 embryonic stem cells.
Project description:Hepatocyte nuclear factor 1B (HNF1B) encodes a transcription factor expressed in developing human kidney epithelia. Heterozygous HNF1B mutations are the commonest monogenic cause of dysplastic kidney malformations (DKMs). To understand their pathobiology, we generated heterozygous HNF1B mutant kidney organoids from CRISPR-Cas9 gene-edited human ESCs and iPSCs reprogrammed from a family with HNF1B-asscociated DKMs. Mutant organoids contained enlarged malformed tubules and displayed deregulated cell turnover. This submission contains kidney tissue samples.
Project description:Nephron progenitor cells (NPCs) self-renew and differentiate into nephrons, the functional units of the kidney. Here we report manipulation of p38 and YAP activity creates a synthetic niche that allows the long-term clonal expansion of primary mouse and human NPCs, and induced NPCs (iNPCs) from human pluripotent stem cells. Cultured iNPCs resemble closely primary human NPCs, generating nephron organoids with abundant distal convoluted tubule cells, which are not observed in published kidney organoids. The synthetic niche reprograms differentiated nephron cells into NPC state, recapitulating the plasticity of developing nephron in vivo. Scalability and ease of genome-editing in the cultured NPCs allow for genome-wide CRISPR screening, identi-fying novel genes associated with kidney development and disease. A rapid, efficient, and scala-ble organoid model for polycystic kidney disease was derived directly from genome-edited NPCs, and validated in drug screen. These technological platforms have broad applications to kidney development, disease, plasticity, and regeneration.
Project description:Podocytes are highly specialised cells within the glomeruli of the kidney that maintain the filtration barrier by forming interdigitating foot processes and slit-diaphragms. Disruption to these features result in proteinuria and glomerulosclerosis. Studies into podocyte biology and disease have previously relied on conditionally immortalised cell lines due to the non- proliferative nature of this cell type. Here we describe an advanced model to study both podocyte and glomerular biology using isolated glomeruli from kidney organoids derived from human pluripotent stem cells.
Project description:A critical event during kidney organogenesis is the differentiation of podocytes, specialized epithelial cells that filter blood plasma to form urine. Podocytes derived from human pluripotent stem cells (hPSC-podocytes) have recently been generated in nephron-like kidney organoids, but the developmental stage of these cells and their capacity to reveal disease mechanisms remains unclear. Here, we show that hPSC-podocytes phenocopy mammalian podocytes at the capillary loop stage (CLS), recapitulating key features of ultrastructure, gene expression, and mutant phenotype. hPSC-podocytes in vitro progressively establish junction-rich basal membranes (nephrin+ podocin+ ZO-1+) and microvillus-rich apical membranes (podocalyxin+), similar to CLS podocytes in vivo. Ultrastructural, biophysical, and transcriptomic analysis of podocalyxin-knockout hPSCs and derived podocytes, generated using CRISPR/Cas9, reveals defects in the assembly of microvilli and lateral spaces between developing podocytes, resulting in failed junctional migration. These defects are phenocopied in CLS glomeruli of podocalyxin-deficient mice, which cannot produce urine, thereby demonstrating that podocalyxin has a conserved and essential role in mammalian podocyte maturation. Defining the maturity of hPSC-podocytes and their capacity to reveal and recapitulate pathophysiological mechanisms establishes a powerful framework for studying human kidney disease and regeneration.
Project description:Kidney organoids are a valuable and innovative model to understand genetic diseases, kidney development and transcriptomic dynamics. However, their proteome has not been analyzed so far. Here, we analyzed the organoid proteome trajectory during differentiation. Genes involved in podocytopathies and cystic kidney diseases were abundantly expressed on protein level, distinguishing organoids from almost every available cell culture model. On their pathway to terminal differentiation, organoids developed increased deposition of extracellular matrix. Single cell transcriptomic analysis suggests that most changes locate to podocytes and early podocyte progenitors. This matrix deposition is different from commonly used animal models of glomerular disease. We grew organoids from two independent batches according to the Freedman protocol, and performed proteomic profiling (Freedman, Brooks et al. 2015, Czerniecki, Cruz et al. 2018). The IPSCs were differentiated for a three-week period until first spheroids from. From day 21 of the culture they were used in our experiments up until day 29, where off-target differentiation of organoids becomes an issue.
Project description:To investigate the impact of various NPHS2 homozygous point mutations on podocyte biology in induced pluripotent stem cell (iPSC)-derived human kidney organoids, an iPSC allelic series was generated from a control fibroblast line and two iPSC lines were derived from patient blood samples (one homozygous R168H and one unaffected relative) iPSCs were differentiated into kidney organoids, organoids glomeruli were harvested and we performed gene expression profiling using data obtained from RNA-seq of 3 sets of 4 organoids for each genotype at D7+14 of our differentiation protocol (Takasato et al, Nature 2016)
Project description:This dataset serves as comparison for PXD029718 using a different organoid differentiation protocol – as requested by reviewers. Kidney organoids are a promising model to study kidney disease, but use is constrained by limited knowledge of their functional protein expression profile. We aimed to define the organoid proteome and transcriptome trajectories over culture duration and upon exposure to TNFα, a cytokine stressor. Older organoids increased deposition of extracellular matrix but decreased expression of glomerular proteins. Single cell transcriptome integration revealed that most proteome changes localized to podocytes, tubular and stromal cells. TNFα-treatment of organoids effected 320 differentially expressed proteins, including cytokines and complement components. Transcript expression of these 320 proteins was significantly higher in individuals with poorer clinical outcomes in proteinuric kidney disease. Key TNFα-associated protein (C3 and VCAM1) expression was increased in both human tubular and organoid kidney cell populations, highlighting the potential for organoids to advance biomarker development. By integrating kidney organoid omic layers, incorporating a disease-relevant cytokine stressor and comparing to human data, we provide crucial evidence of functional relevance of the kidney organoid model to human kidney disease.