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Puapatanakul P, Isaranuwatchai S, Chanakul A, Surintrspanont J, Iampenkhae K, Kanjanabuch T, Suphapeetiporn K, Charu V, Suleiman HY, Praditpornsilpa K, Miner JH. Quantitative assessment of glomerular basement membrane collagen IV α chains in paraffin sections from patients with focal segmental glomerulosclerosis and Alport gene variants. Kidney Int 2024; 105:1049-1057. [PMID: 38401706 PMCID: PMC11032260 DOI: 10.1016/j.kint.2024.01.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 01/05/2024] [Accepted: 01/12/2024] [Indexed: 02/26/2024]
Abstract
Focal segmental glomerulosclerosis (FSGS) lesions have been linked to variants in COL4A3/A4/A5 genes, which are also mutated in Alport syndrome. Although it could be useful for diagnosis, quantitative evaluation of glomerular basement membrane (GBM) type IV collagen (colIV) networks is not widely used to assess these patients. To do so, we developed immunofluorescence imaging for collagen α5(IV) and α1/2(IV) on kidney paraffin sections with Airyscan confocal microscopy that clearly distinguishes GBM collagen α3α4α5(IV) and α1α1α2(IV) as two distinct layers, allowing quantitative assessment of both colIV networks. The ratios of collagen α5(IV):α1/2(IV) mean fluorescence intensities (α5:α1/2 intensity ratios) and thicknesses (α5:α1/2 thickness ratios) were calculated to represent the levels of collagen α3α4α5(IV) relative to α1α1α2(IV). The α5:α1/2 intensity and thickness ratios were comparable across all 11 control samples, while both ratios were significantly and markedly decreased in all patients with pathogenic or likely pathogenic Alport COL4A variants, supporting validity of this approach. Thus, with further validation of this technique, quantitative measurement of GBM colIV subtype abundance by immunofluorescence, may potentially serve to identify the subgroup of patients with FSGS lesions likely to harbor pathogenic COL4A variants who could benefit from genetic testing.
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Affiliation(s)
- Pongpratch Puapatanakul
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Suramath Isaranuwatchai
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Division of Nephrology, Department of Internal Medicine, Chulabhorn Hospital, Chulabhorn Royal Academy, Bangkok, Thailand
| | - Ankanee Chanakul
- Division of Nephrology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Jerasit Surintrspanont
- Department of Pathology, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand; Special Task Force for Activating Research, Department of Pathology, Chulalongkorn University, Bangkok, Thailand
| | - Kroonpong Iampenkhae
- Department of Pathology, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
| | - Talerngsak Kanjanabuch
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Center of Excellence in Kidney Metabolic Disorders, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Kanya Suphapeetiporn
- Division of Medical Genetics and Metabolism, Center of Excellence for Medical Genomics, Department of Pediatrics, Medical Genomic Cluster, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
| | - Vivek Charu
- Department of Pathology, Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Kearkiat Praditpornsilpa
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA.
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Puapatanakul P, Miner JH. Alport syndrome and Alport kidney diseases - elucidating the disease spectrum. Curr Opin Nephrol Hypertens 2024; 33:283-290. [PMID: 38477333 PMCID: PMC10990029 DOI: 10.1097/mnh.0000000000000983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
PURPOSE OF REVIEW With the latest classification, variants in three collagen IV genes, COL4A3 , COL4A4 , and COL4A5 , represent the most prevalent genetic kidney disease in humans, exhibiting diverse, complex, and inconsistent clinical manifestations. This review breaks down the disease spectrum and genotype-phenotype correlations of kidney diseases linked to genetic variants in these genes and distinguishes "classic" Alport syndrome (AS) from the less severe nonsyndromic genetically related nephropathies that we suggest be called "Alport kidney diseases". RECENT FINDINGS Several research studies have focused on the genotype-phenotype correlation under the latest classification scheme of AS. The historic diagnoses of "benign familial hematuria" and "thin basement membrane nephropathy" linked to heterozygous variants in COL4A3 or COL4A4 are suggested to be obsolete, but instead classified as autosomal AS by recent expert consensus due to a significant risk of disease progression. SUMMARY The concept of Alport kidney disease extends beyond classic AS. Patients carrying pathogenic variants in any one of the COL4A3/A4/A5 genes can have variable phenotypes ranging from completely normal/clinically unrecognizable, hematuria without or with proteinuria, or progression to chronic kidney disease and kidney failure, depending on sex, genotype, and interplays of other genetic as well as environmental factors.
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Affiliation(s)
- Pongpratch Puapatanakul
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Jeffrey H. Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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Rezi CK, Aslanyan M, Diwan GD, Cheng T, Chamlali M, Junger K, Anvarian Z, Lorentzen E, Pauly KB, Bahadori Y, Fernandes EF, Qian F, Tosi S, Christensen ST, Pedersen SF, Stromgaard K, Russell RB, Miner JH, Mahjoub MR, Boldt K, Roepman R, Pedersen LB. DLG1 functions upstream of SDCCAG3 and IFT20 to control ciliary targeting of polycystin-2. bioRxiv 2024:2023.11.10.566524. [PMID: 37987012 PMCID: PMC10659422 DOI: 10.1101/2023.11.10.566524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Polarized vesicular trafficking directs specific receptors and ion channels to cilia, but the underlying mechanisms are poorly understood. Here we describe a role for DLG1, a core component of the Scribble polarity complex, in regulating ciliary protein trafficking in kidney epithelial cells. Conditional knockout of Dlg1 in mouse kidney caused ciliary elongation and cystogenesis, and cell-based proximity labelling proteomics and fluorescence microscopy showed alterations in the ciliary proteome upon loss of DLG1. Specifically, the retromer-associated protein SDCCAG3, IFT20 and polycystin-2 (PC2) were reduced in cilia of DLG1 deficient cells compared to control cells. This phenotype was recapitulated in vivo and rescuable by re-expression of wildtype DLG1, but not a Congenital Anomalies of the Kidney and Urinary Tract (CAKUT)-associated DLG1 variant, p.T489R. Finally, biochemical approaches and Alpha Fold modelling suggested that SDCCAG3 and IFT20 form a complex that associates, at least indirectly, with DLG1. Our work identifies a key role for DLG1 in regulating ciliary protein composition and suggests that ciliary dysfunction of the p.T489R DLG1 variant may contribute to CAKUT.
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Goodman KN, Puapatanakul P, Barton KT, He M, Miner JH, Gaut JP. A Case of Congenital Nephrotic Syndrome with Crescents Caused by a Novel Compound Heterozygous Pairing of NPHS1 Genetic Variants. Case Rep Nephrol 2024; 2024:5121375. [PMID: 38444459 PMCID: PMC10914425 DOI: 10.1155/2024/5121375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 02/07/2024] [Accepted: 02/17/2024] [Indexed: 03/07/2024] Open
Abstract
Congenital nephrotic syndrome is an autosomal recessive inherited disorder that manifests as steroid-resistant massive proteinuria in the first three months of life. Defects in the glomerular filtration mechanism are the primary etiology. We present a child who developed severe nephrotic syndrome at two weeks of age and eventually required a bilateral nephrectomy. Genetic testing revealed compound heterozygous variants in NPHS1 including a known pathogenic variant and a missense variant of uncertain significance. Light microscopy revealed crescent formation-an atypical finding in congenital nephrotic syndrome caused by nephrin variants-in addition to focal segmental and global glomerulosclerosis. Electron microscopy showed diffuse podocyte foot process effacement. Confocal and Airyscan immunofluorescence microcopy showed aggregation of nephrin in the podocyte cell body that is not a result of diffuse podocyte foot process effacement as seen in minimal change disease. These findings confirm the novel variant as pathogenic.
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Affiliation(s)
- Kyle N. Goodman
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Pongpratch Puapatanakul
- Division of Nephrology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Kevin T. Barton
- Division of Nephrology, Hypertension and Apheresis, St. Louis Children's Hospital, St. Louis, MO, USA
| | - Mai He
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Jeffrey H. Miner
- Division of Nephrology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Joseph P. Gaut
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
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Langner E, Puapatanakul P, Pudlowski R, Alsabbagh DY, Miner JH, Horani A, Dutcher SK, Brody SL, Wang JT, Suleiman HY, Mahjoub MR. Ultrastructure expansion microscopy (U-ExM) of mouse and human kidneys for analysis of subcellular structures. bioRxiv 2024:2024.02.16.580708. [PMID: 38405695 PMCID: PMC10889020 DOI: 10.1101/2024.02.16.580708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Ultrastructure expansion microscopy (U-ExM) involves the physical magnification of specimens embedded in hydrogels, which allows for super-resolution imaging of subcellular structures using a conventional diffraction-limited microscope. Methods for expansion microscopy exist for several organisms, organs, and cell types, and used to analyze cellular organelles and substructures in nanoscale resolution. Here, we describe a simple step-by-step U-ExM protocol for the expansion, immunostaining, imaging, and analysis of cytoskeletal and organellar structures in kidney tissue. We detail the critical modified steps to optimize isotropic kidney tissue expansion, and preservation of the renal cell structures of interest. We demonstrate the utility of the approach using several markers of renal cell types, centrioles, cilia, the extracellular matrix, and other cytoskeletal elements. Finally, we show that the approach works well on mouse and human kidney samples that were preserved using different fixation and storage conditions. Overall, this protocol provides a simple and cost-effective approach to analyze both pre-clinical and clinical renal samples in high detail, using conventional lab supplies and standard widefield or confocal microscopy.
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Yoshimura Y, Muto Y, Omachi K, Miner JH, Humphreys BD. Elucidating the Proximal Tubule HNF4A Gene Regulatory Network in Human Kidney Organoids. J Am Soc Nephrol 2023; 34:1672-1686. [PMID: 37488681 PMCID: PMC10561821 DOI: 10.1681/asn.0000000000000197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 07/08/2023] [Indexed: 07/26/2023] Open
Abstract
SIGNIFICANCE STATEMENT HNF4 genes promote proximal tubule differentiation in mice, but their function in human nephrogenesis is not fully defined. This study uses human pluripotent stem cell (PSC)-derived kidney organoids as a model to investigate HNF4A and HNF4G functions. The loss of HNF4A , but not HNF4G , impaired reabsorption-related molecule expression and microvilli formation in human proximal tubules. Cleavage under targets and release using nuclease (CUT&RUN) sequencing and CRISPR-mediated transcriptional activation (CRISPRa) further confirm that HNF4A directly regulates its target genes. Human kidney organoids provide a good model for studying transcriptional regulation in human kidney development. BACKGROUND The proximal tubule plays a major role in electrolyte homeostasis. Previous studies have shown that HNF4A regulates reabsorption-related genes and promotes proximal tubule differentiation during murine kidney development. However, the functions and gene regulatory mechanisms of HNF4 family genes in human nephrogenesis have not yet been investigated. METHODS We generated HNF4A -knock out (KO), HNF4G -KO, and HNF4A/4G -double KO human pluripotent stem cell lines, differentiated each into kidney organoids, and used immunofluorescence analysis, electron microscopy, and RNA-seq to analyze them. We probed HNF4A-binding sites genome-wide by cleavage under targets and release using nuclease sequencing in both human adult kidneys and kidney organoid-derived proximal tubular cells. Clustered Regularly Interspaced Short Palindromic Repeats-mediated transcriptional activation validated HNF4A and HNF4G function in proximal tubules during kidney organoid differentiation. RESULTS Organoids lacking HNF4A , but not HNF4G , showed reduced expression of transport-related, endocytosis-related, and brush border-related genes, as well as disorganized brush border structure in the apical lumen of the organoid proximal tubule. Cleavage under targets and release using nuclease revealed that HNF4A primarily bound promoters and enhancers of genes that were downregulated in HNF4A -KO, suggesting direct regulation. Induced expression of HNF4A or HNF4G by CRISPR-mediated transcriptional activation drove increased expression of selected target genes during kidney organoid differentiation. CONCLUSIONS This study reveals regulatory mechanisms of HNF4A and HNF4G during human proximal tubule differentiation. The experimental strategy can be applied more broadly to investigate transcriptional regulation in human kidney development.
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Affiliation(s)
- Yasuhiro Yoshimura
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, Missouri
| | - Yoshiharu Muto
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, Missouri
| | - Kohei Omachi
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, Missouri
| | - Jeffrey H. Miner
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, Missouri
| | - Benjamin D. Humphreys
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, Missouri
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri
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Deltas C, Papagregoriou G, Louka SF, Malatras A, Flinter F, Gale DP, Gear S, Gross O, Hoefele J, Lennon R, Miner JH, Renieri A, Savige J, Turner AN. Genetic Modifiers of Mendelian Monogenic Collagen IV Nephropathies in Humans and Mice. Genes (Basel) 2023; 14:1686. [PMID: 37761826 PMCID: PMC10530214 DOI: 10.3390/genes14091686] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/09/2023] [Accepted: 08/17/2023] [Indexed: 09/29/2023] Open
Abstract
Familial hematuria is a clinical sign of a genetically heterogeneous group of conditions, accompanied by broad inter- and intrafamilial variable expressivity. The most frequent condition is caused by pathogenic (or likely pathogenic) variants in the collagen-IV genes, COL4A3/A4/A5. Pathogenic variants in COL4A5 are responsible for the severe X-linked glomerulopathy, Alport syndrome (AS), while homozygous or compound heterozygous variants in the COL4A3 or the COL4A4 gene cause autosomal recessive AS. AS usually leads to progressive kidney failure before the age of 40-years when left untreated. People who inherit heterozygous COL4A3/A4 variants are at-risk of a slowly progressive form of the disease, starting with microscopic hematuria in early childhood, developing Alport spectrum nephropathy. Sometimes, they are diagnosed with benign familial hematuria, and sometimes with autosomal dominant AS. At diagnosis, they often show thin basement membrane nephropathy, reflecting the uniform thin glomerular basement membrane lesion, inherited as an autosomal dominant condition. On a long follow-up, most patients will retain normal or mildly affected kidney function, while a substantial proportion will develop chronic kidney disease (CKD), even kidney failure at an average age of 55-years. A question that remains unanswered is how to distinguish those patients with AS or with heterozygous COL4A3/A4 variants who will manifest a more aggressive kidney function decline, requiring prompt medical intervention. The hypothesis that a subgroup of patients coinherit additional genetic modifiers that exacerbate their clinical course has been investigated by several researchers. Here, we review all publications that describe the potential role of candidate genetic modifiers in patients and include a summary of studies in AS mouse models.
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Affiliation(s)
- Constantinos Deltas
- School of Medicine, University of Cyprus, Nicosia 2109, Cyprus
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Gregory Papagregoriou
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Stavroula F. Louka
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Apostolos Malatras
- biobank.cy Center of Excellence in Biobanking and Biomedical Research, University of Cyprus, Nicosia 2109, Cyprus
| | - Frances Flinter
- Clinical Genetics Department, Guy’s & St Thomas’ NHS Foundation Trust, London SE1 9RT, UK
| | - Daniel P. Gale
- Department of Renal Medicine, University College London, London NW3 2PF, UK
| | | | - Oliver Gross
- Clinic for Nephrology and Rheumatology, University Medicine Goettingen, 37075 Goettingen, Germany
| | - Julia Hoefele
- Institute of Human Genetics, Klinikum Rechts der Isar, School of Medicine & Health, Technical University Munich, 81675 Munich, Germany
| | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, University of Manchester, Manchester M13 9WU, UK
| | - Jeffrey H. Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Alessandra Renieri
- Medical Genetics, University of Siena, 53100 Siena, Italy
- Med Biotech Hub and Competence Center, Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy
- Genetica Medica, Azienda Ospedaliero-Universitaria Senese, 53100 Siena, Italy
| | - Judy Savige
- Department of Medicine (Melbourne Health and Northern Health), The University of Melbourne, Parkville, VIC 3052, Australia
| | - A. Neil Turner
- Renal Medicine, Royal Infirmary, University of Edinburgh, Edinburgh EH16 4UX, UK
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Yoshimura Y, Muto Y, Ledru N, Wu H, Omachi K, Miner JH, Humphreys BD. A single-cell multiomic analysis of kidney organoid differentiation. Proc Natl Acad Sci U S A 2023; 120:e2219699120. [PMID: 37155865 DOI: 10.1073/pnas.2219699120] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023] Open
Abstract
Kidney organoids differentiated from pluripotent stem cells are powerful models of kidney development and disease but are characterized by cell immaturity and off-target cell fates. Comparing the cell-specific gene regulatory landscape during organoid differentiation with human adult kidney can serve to benchmark progress in differentiation at the epigenome and transcriptome level for individual organoid cell types. Using single-cell multiome and histone modification analysis, we report more broadly open chromatin in organoid cell types compared to the human adult kidney. We infer enhancer dynamics by cis-coaccessibility analysis and validate an enhancer driving transcription of HNF1B by CRISPR interference both in cultured proximal tubule cells and also during organoid differentiation. Our approach provides an experimental framework to judge the cell-specific maturation state of human kidney organoids and shows that kidney organoids can be used to validate individual gene regulatory networks that regulate differentiation.
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Affiliation(s)
- Yasuhiro Yoshimura
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Yoshiharu Muto
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Nicolas Ledru
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Haojia Wu
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Kohei Omachi
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Benjamin D Humphreys
- Division of Nephrology, Department of Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
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Affiliation(s)
- Sybille Koehler
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Hamburg Center for Kidney Health (HCKH), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, MO, United States
| | - Alexander Staruschenko
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL, United States.,Hypertension and Kidney Research Center, University of South Florida, Tampa, FL, United States
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Omachi K, O'Carroll C, Miner JH. PPAR δ Agonism Ameliorates Renal Fibrosis in an Alport Syndrome Mouse Model. Kidney360 2023; 4:341-348. [PMID: 36657027 PMCID: PMC10103270 DOI: 10.34067/kid.0006662022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/21/2022] [Indexed: 12/05/2022]
Abstract
Key Points A peroxisome proliferator-activated receptor δ agonist, REN001, ameliorates kidney dysfunction in a mouse model of Alport syndrome. REN001 suppresses glomerular injury and renal fibrosis. REN001 decreases the levels of inflammation- and fibrosis-related proteins. Background Alport syndrome is a genetic kidney disease caused by mutation in any of the COL4A3 , COL4A4 , or COL4A5 genes encoding the type IV collagen α 3, α 4, and α 5 chains. Defects of type IV collagen α 3α 4α 5 cause glomerular basement membrane abnormalities and lead to defects in glomerular filtration and ESKD. Treatment with angiotensin-converting enzyme inhibitors (ACEis) dramatically slows disease progression but does not stop progression to renal failure. Therefore, novel therapeutic options with different modes of action from ACEis are needed. Peroxisome proliferator-activated receptor (PPAR) δ agonists have shown renoprotective effects in several acute kidney injury mouse models. In this study, we investigated the effects of a potent and selective PPARδ agonist, REN001 (formerly HPP593), in a mouse model of Alport syndrome. Methods We administered REN001 from the early stages to the late stages of disease by once daily intraperitoneal injections. Results REN001 treatment halved proteinuria at the late stages of disease in Col4a3 −/− mice. BUN levels were also decreased, and histological and molecular analyses showed that REN001 ameliorated renal inflammation and fibrosis. Conclusions These results indicate that REN001 slows kidney disease progression in Alport mice. REN001 has a different mechanism of action from ACEis, so we, therefore, hypothesize that combining the two treatments may show additive effects to attenuate renal injury and slow progression to renal failure.
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Affiliation(s)
- Kohei Omachi
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | | | - Jeffrey H. Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
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Kohler J, Omachi K, Charu V, Miner JH, Bhalla V. A COL4A4-G394S Variant and Impaired Collagen IV Trimerization in a Patient with Mild Alport Syndrome. Kidney360 2022; 3:1899-1908. [PMID: 36514391 PMCID: PMC9717634 DOI: 10.34067/kid.0005472022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 10/18/2022] [Indexed: 04/14/2023]
Abstract
Background Missense variants in COL4A genes are often found in patients with an Alport syndrome-like presentation, but their pathogenicity is not always clear. We encountered a woman with microscopic hematuria and proteinuria at 33 years of age with a diagnosis of thin basement membrane disease who was approaching end stage kidney disease at 59 years of age. We hypothesized that this patient's kidney disease was within the spectrum of Alport syndrome. Methods We used histologic, genetic, and biochemical approaches to investigate the mechanisms of kidney disease. By immunofluorescence, we investigated collagen IV chain composition of the glomerular basement membrane (GBM). We employed targeted sequencing to search for pathogenic variants in COL4A and other relevant genes. We utilized N- and C-terminal split NanoLuciferase assays to determine the effect of a novel COL4A4 variant of uncertain significance (VUS) on collagen IV heterotrimer formation in vitro. We transfected COL4A4 expression constructs with split NanoLuciferase fragment-fused COL4A3 and COL4A5 constructs into human embryonic kidney 293T cells. To assay for α3α4α5(IV) heterotrimer formation and secretion, we measured luminescence in cell lysates and culture supernatants from transfected cells. Results Immunostaining suggested that the collagen α3α4α5(IV) network was present throughout the patient's GBMs. DNA sequencing revealed a novel homozygous VUS: COL4A4 c.1180G>A (p. Gly394Ser). In the C-terminal split luciferase-based α3α4α5(IV) heterotrimer formation assays, luminescence levels for G394S were comparable to WT, but in the N-terminal tag assays, the extracellular luminescence levels for G394S were decreased by approximately 50% compared with WT. Conclusions Our cell-based assay provides a platform to test COL4 VUS and shows that G394S impairs assembly of the α3α4α5(IV) N-terminus and subsequent trimer secretion. These data suggest that the COL4A4-G394S variant is pathogenic and causes an atypical mild form of autosomal recessive Alport syndrome.
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Affiliation(s)
- Jennefer Kohler
- Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, California
| | - Kohei Omachi
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Vivek Charu
- Department of Pathology, Stanford University School of Medicine, Stanford, California
| | - Jeffrey H. Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Vivek Bhalla
- Division of Nephrology, Department of Medicine, Stanford School of Medicine, Stanford, California
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12
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Muto Y, Dixon EE, Yoshimura Y, Wu H, Omachi K, Ledru N, Wilson PC, King AJ, Eric Olson N, Gunawan MG, Kuo JJ, Cox JH, Miner JH, Seliger SL, Woodward OM, Welling PA, Watnick TJ, Humphreys BD. Defining cellular complexity in human autosomal dominant polycystic kidney disease by multimodal single cell analysis. Nat Commun 2022; 13:6497. [PMID: 36310237 PMCID: PMC9618568 DOI: 10.1038/s41467-022-34255-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 10/17/2022] [Indexed: 12/25/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the leading genetic cause of end stage renal disease characterized by progressive expansion of kidney cysts. To better understand the cell types and states driving ADPKD progression, we analyze eight ADPKD and five healthy human kidney samples, generating single cell multiomic atlas consisting of ~100,000 single nucleus transcriptomes and ~50,000 single nucleus epigenomes. Activation of proinflammatory, profibrotic signaling pathways are driven by proximal tubular cells with a failed repair transcriptomic signature, proinflammatory fibroblasts and collecting duct cells. We identify GPRC5A as a marker for cyst-lining collecting duct cells that exhibits increased transcription factor binding motif availability for NF-κB, TEAD, CREB and retinoic acid receptors. We identify and validate a distal enhancer regulating GPRC5A expression containing these motifs. This single cell multiomic analysis of human ADPKD reveals previously unrecognized cellular heterogeneity and provides a foundation to develop better diagnostic and therapeutic approaches.
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Affiliation(s)
- Yoshiharu Muto
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Eryn E Dixon
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Yasuhiro Yoshimura
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Haojia Wu
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Kohei Omachi
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicolas Ledru
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Parker C Wilson
- Department of Pathology and Immunology, Washington University in St. Louis, St. Louis, MO, USA
| | | | | | | | - Jay J Kuo
- Chinook Therapeutics, Inc., Vancouver, BC, Canada
| | | | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Stephen L Seliger
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Owen M Woodward
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | - Terry J Watnick
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Benjamin D Humphreys
- Division of Nephrology, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
- Department of Developmental Biology, Washington University in St. Louis, St. Louis, MO, USA.
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13
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Jiang S, Alisafaei F, Huang YY, Hong Y, Peng X, Qu C, Puapatanakul P, Jain S, Miner JH, Genin GM, Suleiman HY. An ex vivo culture model of kidney podocyte injury reveals mechanosensitive, synaptopodin-templating, sarcomere-like structures. Sci Adv 2022; 8:eabn6027. [PMID: 36044576 PMCID: PMC9432837 DOI: 10.1126/sciadv.abn6027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Chronic kidney diseases are widespread and incurable. The biophysical mechanisms underlying them are unclear, in part because material systems for reconstituting the microenvironment of relevant kidney cells are limited. A critical question is how kidney podocytes (glomerular epithelial cells) regenerate foot processes of the filtration apparatus following injury. Recently identified sarcomere-like structures (SLSs) with periodically spaced myosin IIA and synaptopodin appear in injured podocytes in vivo. We hypothesized that SLSs template synaptopodin in the initial stages of recovery in response to microenvironmental stimuli and tested this hypothesis by developing an ex vivo culture system that allows control of the podocyte microenvironment. Results supported our hypothesis. SLSs in podocytes that migrated from isolated kidney glomeruli presented periodic synaptopodin-positive clusters that nucleated peripheral, foot process-like extensions. SLSs were mechanoresponsive to actomyosin inhibitors and substrate stiffness. Results suggest SLSs as mechanobiological mediators of podocyte recovery and as potential targets for therapeutic intervention.
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Affiliation(s)
- Shumeng Jiang
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Farid Alisafaei
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical and Industrial Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - Yin-Yuan Huang
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Yuan Hong
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Xiangjun Peng
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Chengqing Qu
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Pongpratch Puapatanakul
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Sanjay Jain
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeffrey H. Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Guy M. Genin
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Hani Y. Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
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14
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Omachi K, Miner JH. Comparative analysis of dCas9-VP64 variants and multiplexed guide RNAs mediating CRISPR activation. PLoS One 2022; 17:e0270008. [PMID: 35763517 PMCID: PMC9239446 DOI: 10.1371/journal.pone.0270008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 06/01/2022] [Indexed: 11/26/2022] Open
Abstract
CRISPR/Cas9-mediated transcriptional activation (CRISPRa) is a powerful tool for investigating complex biological phenomena. Although CRISPRa approaches based on the VP64 transcriptional activator have been widely studied in both cultured cells and in animal models and exhibit great versatility for various cell types and developmental stages in vivo, different dCas9-VP64 versions have not been rigorously compared. Here, we compared different dCas9-VP64 constructs in identical contexts, including the cell lines used and the transfection conditions, for their ability to activate endogenous and exogenous genes. Moreover, we investigated the optimal approach for VP64 addition to VP64- and p300-based constructs. We found that MS2-MCP-scaffolded VP64 enhanced basal dCas9-VP64 and dCas9-p300 activity better than did direct VP64 fusion to the N-terminus of dCas9. dCas9-VP64+MCP-VP64 and dCas9-p300+MCP-VP64 were superior to VP64-dCas9-VP64 for all target genes tested. Furthermore, multiplexing gRNA expression with dCas9-VP64+MCP-VP64 or dCas9-p300+MCP-VP64 significantly enhanced endogenous gene activation to a level comparable to CRISPRa-SAM with a single gRNA. Our findings demonstrate improvement of the dCas9-VP64 CRISPRa system and contribute to development of a versatile, efficient CRISPRa platform.
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Affiliation(s)
- Kohei Omachi
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Jeffrey H. Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri, United States of America
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15
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Omachi K, Kai H, Roberge M, Miner JH. Full-length and split-NanoLuc reporters identify pathogenic COL4A5 nonsense mutations susceptible to premature termination codon readthrough. iScience 2022; 25:103891. [PMID: 35243249 PMCID: PMC8866893 DOI: 10.1016/j.isci.2022.103891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 12/22/2021] [Accepted: 02/04/2022] [Indexed: 11/02/2022] Open
Abstract
Alport syndrome, a disease of kidney, ear, and eye, is caused by pathogenic variants in the COL4A3, COL4A4, or COL4A5 genes encoding collagen α3α4α5(IV) of basement membranes. Collagen IV chains that are truncated due to nonsense variants/premature termination codons (PTCs) cannot assemble into heterotrimers or incorporate into basement membranes. To investigate the feasibility of PTC readthrough therapy for Alport syndrome, we utilized two NanoLuc reporters in transfected cells: full-length for monitoring translation, and a split version for assessing readthrough product function. Full-length assays of 49 COL4A5 nonsense variants identified eleven as susceptible to PTC readthrough using various readthrough drugs. In split-NanoLuc assays, the predicted missense α5(IV) readthrough products of five nonsense mutations could heterotrimerize with α3(IV) and α4(IV). Readthrough was also observed in kidney cells from an engineered Col4a5 PTC mouse model. These results suggest that readthrough therapy is a feasible approach for a fraction of patients with Alport syndrome. NanoLuc fusion constructs identified COL4A5 mutants susceptible to PTC readthrough Readthrough enhancer and “designer” compounds promoted PTC readthrough Split-NanoLuc fusion constructs identified functional missense readthrough products Cultured Col4a5 nonsense mutant mouse kidney cells were susceptible to readthrough
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16
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Qu C, Roth R, Puapatanakul P, Loitman C, Hammad D, Genin GM, Miner JH, Suleiman HY. Three-Dimensional Visualization of the Podocyte Actin Network Using Integrated Membrane Extraction, Electron Microscopy, and Machine Learning. J Am Soc Nephrol 2022; 33:155-173. [PMID: 34758982 PMCID: PMC8763187 DOI: 10.1681/asn.2021020182] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 10/19/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Actin stress fibers are abundant in cultured cells, but little is known about them in vivo. In podocytes, much evidence suggests that mechanobiologic mechanisms underlie podocyte shape and adhesion in health and in injury, with structural changes to actin stress fibers potentially responsible for pathologic changes to cell morphology. However, this hypothesis is difficult to rigorously test in vivo due to challenges with visualization. A technology to image the actin cytoskeleton at high resolution is needed to better understand the role of structures such as actin stress fibers in podocytes. METHODS We developed the first visualization technique capable of resolving the three-dimensional cytoskeletal network in mouse podocytes in detail, while definitively identifying the proteins that comprise this network. This technique integrates membrane extraction, focused ion-beam scanning electron microscopy, and machine learning image segmentation. RESULTS Using isolated mouse glomeruli from healthy animals, we observed actin cables and intermediate filaments linking the interdigitated podocyte foot processes to newly described contractile actin structures, located at the periphery of the podocyte cell body. Actin cables within foot processes formed a continuous, mesh-like, electron-dense sheet that incorporated the slit diaphragms. CONCLUSIONS Our new technique revealed, for the first time, the detailed three-dimensional organization of actin networks in healthy podocytes. In addition to being consistent with the gel compression hypothesis, which posits that foot processes connected by slit diaphragms act together to counterbalance the hydrodynamic forces across the glomerular filtration barrier, our data provide insight into how podocytes respond to mechanical cues from their surrounding environment.
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Affiliation(s)
- Chengqing Qu
- Department of Mechanical Engineering, National Science Foundation Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, Missouri
| | - Robyn Roth
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
| | | | - Charles Loitman
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Dina Hammad
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Guy M. Genin
- Department of Mechanical Engineering, National Science Foundation Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, Missouri
| | - Jeffrey H. Miner
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri,Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Hani Y. Suleiman
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
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17
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Taniguchi Y, Nagano C, Sekiguchi K, Tashiro A, Sugawara N, Sakaguchi H, Umeda C, Aoto Y, Ishiko S, Rossanti R, Sakakibara N, Horinouchi T, Yamamura T, Kondo A, Nagai S, Nagase H, Iijima K, Miner JH, Nozu K. Clear Evidence of LAMA5 Gene Biallelic Truncating Variants Causing Infantile Nephrotic Syndrome. Kidney360 2021; 2:1968-1978. [PMID: 35419533 PMCID: PMC8986055 DOI: 10.34067/kid.0004952021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 10/15/2021] [Indexed: 02/04/2023]
Abstract
Background Pathogenic variants in single genes encoding podocyte-associated proteins have been implicated in about 30% of steroid-resistant nephrotic syndrome (SRNS) patients in children. However, LAMA5 gene biallelic variants have been identified in only seven patients so far, and most are missense variants of unknown significance. Furthermore, no functional analysis had been conducted for all but one of these variants. Here, we report three patients with LAMA5 gene biallelic truncating variants manifesting infantile nephrotic syndrome, and one patient with SRNS with biallelic LAMA5 missense variants. Methods We conducted comprehensive gene screening of Japanese patients with severe proteinuria. With the use of targeted next-generation sequencing, 62 podocyte-related genes were screened in 407 unrelated patients with proteinuria. For the newly discovered LAMA5 variants, we conducted in vitro heterotrimer formation assays. Results Biallelic truncating variants in the LAMA5 gene (NM_005560) were detected in three patients from two families. All patients presented with proteinuria within 6 months of age. Patients 1 and 2 were siblings possessing a nonsense variant (c.9232C>T, p.[Arg3078*]) and a splice site variant (c.1282 + 1G>A) that led to exon 9 skipping and a frameshift. Patient 3 had a remarkable irregular contour of the glomerular basement membrane. She was subsequently found to have a nonsense variant (c.8185C>T, p.[Arg2720*]) and the same splice site variant in patients 1 and 2. By in vitro heterotrimer formation assays, both truncating variants produced smaller laminin α5 proteins that nevertheless formed trimers with laminin β1 and γ1 chains. Patient 4 showed SRNS at the age of 8 years, and carried compound heterozygous missense variants (c.1493C>T, p.[Ala498Val] and c.8399G>A, p.[Arg2800His]). Conclusions Our patients showed clear evidence of biallelic LAMA5 truncating variants causing infantile nephrotic syndrome. We also discerned the clinical and pathologic characteristics observed in LAMA5-related nephropathy. LAMA5 variant screening should be performed in patients with congenital/infantile nephrotic syndrome.
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Affiliation(s)
- Yukimasa Taniguchi
- Division of Matrixome Research and Application, Osaka University, Osaka, Japan
| | - China Nagano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Kiyotoshi Sekiguchi
- Division of Matrixome Research and Application, Osaka University, Osaka, Japan
| | - Atsushi Tashiro
- Department of Pediatrics, Japan Community Health Care Organization Chukyo Hospital, Aichi, Japan
| | - Noriko Sugawara
- Department of Pediatrics, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Haruhide Sakaguchi
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan
| | - Chisato Umeda
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan
| | - Yuya Aoto
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Shinya Ishiko
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Rini Rossanti
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Nana Sakakibara
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Tomoko Horinouchi
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Atsushi Kondo
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Sadayuki Nagai
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Hiroaki Nagase
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Kazumoto Iijima
- Hyogo Prefectural Kobe Children’s Hospital, Hyogo, Japan,Department of Advanced Pediatric Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Jeffrey H. Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
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18
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Randles MJ, Lausecker F, Kong Q, Suleiman H, Reid G, Kolatsi-Joannou M, Davenport B, Tian P, Falcone S, Potter P, Van Agtmael T, Norman JT, Long DA, Humphries MJ, Miner JH, Lennon R. Identification of an Altered Matrix Signature in Kidney Aging and Disease. J Am Soc Nephrol 2021; 32:1713-1732. [PMID: 34049963 PMCID: PMC8425653 DOI: 10.1681/asn.2020101442] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 03/15/2021] [Accepted: 03/22/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Accumulation of extracellular matrix in organs and tissues is a feature of both aging and disease. In the kidney, glomerulosclerosis and tubulointerstitial fibrosis accompany the decline in function, which current therapies cannot address, leading to organ failure. Although histologic and ultrastructural patterns of excess matrix form the basis of human disease classifications, a comprehensive molecular resolution of abnormal matrix is lacking. METHODS Using mass spectrometry-based proteomics, we resolved matrix composition over age in mouse models of kidney disease. We compared the changes in mice with a global characterization of human kidneymatrix during aging and to existing kidney disease datasets to identify common molecular features. RESULTS Ultrastructural changes in basement membranes are associated with altered cell adhesion and metabolic processes and with distinct matrix proteomes during aging and kidney disease progression in mice. Within the altered matrix, basement membrane components (laminins, type IV collagen, type XVIII collagen) were reduced and interstitial matrix proteins (collagens I, III, VI, and XV; fibrinogens; and nephronectin) were increased, a pattern also seen in human kidney aging. Indeed, this signature of matrix proteins was consistently modulated across all age and disease comparisons, and the increase in interstitial matrix was also observed in human kidney disease datasets. CONCLUSIONS This study provides deep molecular resolution of matrix accumulation in kidney aging and disease, and identifies a common signature of proteins that provides insight into mechanisms of response to kidney injury and repair.
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Affiliation(s)
- Michael J. Randles
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Franziska Lausecker
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Qingyang Kong
- Department of Renal Medicine, University College London, London, United Kingdom
| | - Hani Suleiman
- Renal Division, Washington University School of Medicine, Saint Louis, Missouri
| | - Graeme Reid
- Department of Histopathology, Manchester Royal Infirmary, Manchester University Hospitals National Health Service Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Maria Kolatsi-Joannou
- Developmental Biology and Cancer Programme, Great Ormond Institute of Child Health, University College London, London, United Kingdom
| | - Bernard Davenport
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Pinyuan Tian
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Sara Falcone
- Centre for Cellular and Molecular Physiology, University of Oxford, Oxford, United Kingdom
| | - Paul Potter
- Department Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Tom Van Agtmael
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jill T. Norman
- Department of Renal Medicine, University College London, London, United Kingdom
| | - David A. Long
- Developmental Biology and Cancer Programme, Great Ormond Institute of Child Health, University College London, London, United Kingdom
| | - Martin J. Humphries
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Jeffrey H. Miner
- Renal Division, Washington University School of Medicine, Saint Louis, Missouri
| | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom,Department of Paediatric Nephrology, Royal Manchester Children’s Hospital, Manchester University Hospitals National Health Service Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
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19
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Abstract
Synaptopodin (Synpo) is an actin-associated protein in podocyte foot processes. By generating mice that completely lack Synpo, we previously showed that Synpo is dispensable for normal kidney function. However, lack of Synpo worsened adriamycin-induced nephropathy, indicating a protective role for Synpo in injured podocytes. Here, we investigated whether lack of Synpo directly impacts a genetic disease, Alport syndrome (AS), because Synpo is reduced in podocytes of affected humans and mice; whether this is merely an association or pathogenic is unknown. We used collagen type IV-α5 (Col4a5) mutant mice, which model X-linked AS, showing glomerular basement membrane (GBM) abnormalities, eventual foot process effacement, and progression to end-stage kidney disease. We intercrossed mice carrying mutations in Synpo and Col4a5 to produce double-mutant mice. Urine and tissue were taken at select time points to evaluate albuminuria, histopathology, and glomerular capillary wall composition and ultrastructure. Lack of Synpo in Col4a5-/Y, Col4a5-/-, or Col4a5+/- Alport mice led to the acceleration of disease progression, including more severe proteinuria and glomerulosclerosis. Absence of Synpo attenuated the shift of myosin IIA from the podocyte cell body and major processes to actin cables near the GBM in the areas of effacement. We speculate that this is mechanistically associated with enhanced loss of podocytes due to easier detachment from the GBM. We conclude that Synpo deletion exacerbates the disease phenotype in Alport mice, revealing the podocyte actin cytoskeleton as a target for therapy in patients with AS.NEW & NOTEWORTHY Alport syndrome (AS) is a hereditary disease of the glomerular basement with hematuria and proteinuria. Podocytes eventually exhibit foot process effacement, indicating actin cytoskeletal changes. To investigate how cytoskeletal changes impact podocytes, we generated Alport mice lacking synaptopodin, an actin-binding protein in foot processes. Analysis showed a more rapid disease progression, demonstrating that synaptopodin is protective. This suggests that the actin cytoskeleton is a target for therapy in AS and perhaps other glomerular diseases.
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Affiliation(s)
- Liang Ning
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
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20
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Kikkawa Y, Hashimoto T, Takizawa K, Urae S, Masuda H, Matsunuma M, Yamada Y, Hamada K, Nomizu M, Liapis H, Hisano M, Akioka Y, Miura K, Hattori M, Miner JH, Harita Y. Laminin β2 variants associated with isolated nephropathy that impact matrix regulation. JCI Insight 2021; 6:145908. [PMID: 33749661 PMCID: PMC8026196 DOI: 10.1172/jci.insight.145908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/10/2021] [Indexed: 11/17/2022] Open
Abstract
Mutations in LAMB2, encoding laminin β2, cause Pierson syndrome and occasionally milder nephropathy without extrarenal abnormalities. The most deleterious missense mutations that have been identified affect primarily the N-terminus of laminin β2. On the other hand, those associated with isolated nephropathy are distributed across the entire molecule, and variants in the β2 LEa-LF-LEb domains are exclusively found in cases with isolated nephropathy. Here we report the clinical features of mild isolated nephropathy associated with 3 LAMB2 variants in the LEa-LF-LEb domains (p.R469Q, p.G699R, and p.R1078C) and their biochemical characterization. Although Pierson syndrome missense mutations often inhibit laminin β2 secretion, the 3 recombinant variants were secreted as efficiently as WT. However, the β2 variants lost pH dependency for heparin binding, resulting in aberrant binding under physiologic conditions. This suggests that the binding of laminin β2 to negatively charged molecules is involved in glomerular basement membrane (GBM) permselectivity. Moreover, the excessive binding of the β2 variants to other laminins appears to lead to their increased deposition in the GBM. Laminin β2 also serves as a potentially novel cell-adhesive ligand for integrin α4β1. Our findings define biochemical functions of laminin β2 variants influencing glomerular filtration that may underlie the pathogenesis of isolated nephropathy caused by LAMB2 abnormalities.
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Affiliation(s)
- Yamato Kikkawa
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Taeko Hashimoto
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan.,Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Keiichi Takizawa
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Seiya Urae
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Haruka Masuda
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Masumi Matsunuma
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Yuji Yamada
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Keisuke Hamada
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Motoyoshi Nomizu
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Helen Liapis
- Department of Pathology and Immunology and Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Masataka Hisano
- Department of Nephrology, Chiba Children's Hospital, Chiba, Japan
| | - Yuko Akioka
- Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan.,Department of Pediatrics, Faculty of Medicine, Saitama Medical University, Saitama, Japan
| | - Kenichiro Miura
- Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Motoshi Hattori
- Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Yutaka Harita
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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21
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Kim JJ, David JM, Wilbon SS, Santos JV, Patel DM, Ahmad A, Mitrofanova A, Liu X, Mallela SK, Ducasa GM, Ge M, Sloan AJ, Al-Ali H, Boulina M, Mendez AJ, Contreras GN, Prunotto M, Sohail A, Fridman R, Miner JH, Merscher S, Fornoni A. Discoidin domain receptor 1 activation links extracellular matrix to podocyte lipotoxicity in Alport syndrome. EBioMedicine 2020; 63:103162. [PMID: 33340991 PMCID: PMC7750578 DOI: 10.1016/j.ebiom.2020.103162] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/21/2020] [Accepted: 11/24/2020] [Indexed: 12/11/2022] Open
Abstract
Background Discoidin domain receptor 1 (DDR1) is a receptor tyrosine kinase that is activated by collagens that is involved in the pathogenesis of fibrotic disorders. Interestingly, de novo production of the collagen type I (Col I) has been observed in Col4a3 knockout mice, a mouse model of Alport Syndrome (AS mice). Deletion of the DDR1 in AS mice was shown to improve survival and renal function. However, the mechanisms driving DDR1-dependent fibrosis remain largely unknown. Methods Podocyte pDDR1 levels, Collagen and cluster of differentiation 36 (CD36) expression was analyzed by Real-time PCR and Western blot. Lipid droplet accumulation and content was determined using Bodipy staining and enzymatic analysis. CD36 and DDR1 interaction was determined by co-immunoprecipitation. Creatinine, BUN, albuminuria, lipid content, and histological and morphological assessment of kidneys harvested from AS mice treated with Ezetimibe and/or Ramipril or vehicle was performed. Findings We demonstrate that Col I-mediated DDR1 activation induces CD36-mediated podocyte lipotoxic injury. We show that Ezetimibe interferes with the CD36/DDR1 interaction in vitro and prevents lipotoxicity in AS mice thus preserving renal function similarly to ramipril. Interpretation Our study suggests that Col I/DDR1-mediated lipotoxicity contributes to renal failure in AS and that targeting this pathway may represent a new therapeutic strategy for patients with AS and with chronic kidney diseases (CKD) associated with Col4 mutations. Funding This study is supported by the NIH grants R01DK117599, R01DK104753, R01CA227493, U54DK083912, UM1DK100846, U01DK116101, UL1TR000460 (Miami Clinical Translational Science Institute, National Center for Advancing Translational Sciences and the National Institute on Minority Health and Health Disparities), F32DK115109, Hoffmann-La Roche and Alport Syndrome Foundation.
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Affiliation(s)
- Jin-Ju Kim
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States.
| | - Judith M David
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Sydney S Wilbon
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Javier V Santos
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Devang M Patel
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - Anis Ahmad
- Department of Radiation Oncology, University of Miami, FL 33136, United States
| | - Alla Mitrofanova
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States; Department of Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, United States
| | - Xiaochen Liu
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Shamroop K Mallela
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Gloria M Ducasa
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Mengyuan Ge
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Alexis J Sloan
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Hassan Al-Ali
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Marcia Boulina
- Diabetes Research Institute, University of Miami Miller School of Medicine, Miami, FL 33136, United States
| | - Armando J Mendez
- Diabetes Research Institute, University of Miami Miller School of Medicine, Miami, FL 33136, United States
| | - Gabriel N Contreras
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Marco Prunotto
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel, Switzerland; School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
| | - Anjum Sohail
- Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
| | - Rafael Fridman
- Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Sandra Merscher
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States
| | - Alessia Fornoni
- Katz Family Division of Nephrology and Hypertension, Drug Discovery center, Department of Medicine, University of Miami Miller School of Medicine, 1580 NW 10th Ave, Miami, FL 33136, United States.
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22
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Marahrens B, Schulze A, Wysocki J, Lin MH, Ye M, Kanwar YS, Bader M, Velez JCQ, Miner JH, Batlle D. Knockout of aminopeptidase A in mice causes functional alterations and morphological glomerular basement membrane changes in the kidneys. Kidney Int 2020; 99:900-913. [PMID: 33316280 DOI: 10.1016/j.kint.2020.11.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 10/28/2020] [Accepted: 11/19/2020] [Indexed: 11/29/2022]
Abstract
Aminopeptidase A is one of the most potent enzymes within the renin-angiotensin system in terms of angiotensin II degradation. Here, we examined whether there is a kidney phenotype and any compensatory changes in other renin angiotensin system enzymes involved in the metabolism of angiotensin II associated with aminopeptidase A deficiency. Kidneys harvested from aminopeptidase A knockout mice were examined by light and electron microscopy, immunohistochemistry and immunofluorescence. Kidney angiotensin II levels and the ability of renin angiotensin system enzymes in the glomerulus to degrade angiotensin II ex vivo, their activities, protein and mRNA levels in kidney lysates were evaluated. Knockout mice had increased blood pressure and mild glomerular mesangial expansion without significant albuminuria. By electron microscopy, knockout mice exhibited a mild increase of the mesangial matrix, moderate thickening of the glomerular basement membrane but a striking appearance of knob-like structures. These knobs were seen in both male and female mice and persisted after the treatment of hypertension. In isolated glomeruli from knockout mice, the level of angiotensin II was more than three-fold higher as compared to wild type control mice. In kidney lysates from knockout mice angiotensin converting enzyme activity, protein and mRNA levels were markedly decreased possibly as a compensatory mechanism to reduce angiotensin II formation. Thus, our findings support a role for aminopeptidase A in the maintenance of glomerular structure and intra-kidney homeostasis of angiotensin peptides.
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Affiliation(s)
- Benedikt Marahrens
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University/Feinberg School of Medicine, Chicago, Illinois, USA; Charité University Medicine Berlin, Berlin, Germany
| | - Arndt Schulze
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University/Feinberg School of Medicine, Chicago, Illinois, USA; Charité University Medicine Berlin, Berlin, Germany
| | - Jan Wysocki
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University/Feinberg School of Medicine, Chicago, Illinois, USA
| | - Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Minghao Ye
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University/Feinberg School of Medicine, Chicago, Illinois, USA
| | - Yashpal S Kanwar
- Department of Pathology, Northwestern University/Feinberg School of Medicine, Chicago, Illinois, USA
| | - Michael Bader
- Charité University Medicine Berlin, Berlin, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany; Max-Delbrück-Center for Molecular Medicine, Berlin, Germany; Institute for Biology, University of Lübeck, Lübeck, Germany
| | - Juan Carlos Q Velez
- Department of Nephrology, Ochsner Clinic Foundation, New Orleans, Louisiana, USA
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Daniel Batlle
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University/Feinberg School of Medicine, Chicago, Illinois, USA.
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23
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Ning L, Suleiman HY, Miner JH. Synaptopodin Is Dispensable for Normal Podocyte Homeostasis but Is Protective in the Context of Acute Podocyte Injury. J Am Soc Nephrol 2020; 31:2815-2832. [PMID: 32938649 DOI: 10.1681/asn.2020050572] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 07/27/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Synaptopodin (Synpo) is an actin-associated protein in podocytes and dendritic spines. Many functions in regulating the actin cytoskeleton via RhoA and other pathways have been ascribed to Synpo, yet no pathogenic mutations in the SYNPO gene have been discovered in patients. Naturally occurring Synpo isoforms are known (Synpo-short and -long), and a novel truncated version (Synpo-T) is upregulated in podocytes from Synpo mutant mice. Synpo-T maintains some Synpo functions, which may prevent a podocyte phenotype from emerging in unchallenged mutant mice. METHODS Novel mouse models were generated to further investigate the functions of Synpo. In one, CRISPR/Cas9 deleted most of the Synpo gene, preventing production of any detectable Synpo protein. Two other mutant strains made truncated versions of the protein. Adriamycin injections were used to challenge the mice, and Synpo functions were investigated in primary cultured podocytes. RESULTS Mice that could not make detectable Synpo (Synpo -/- ) did not develop any kidney abnormalities up to 12 months of age. However, Synpo -/- mice were more susceptible to Adriamycin nephropathy. In cultured primary podocytes from mutant mice, the absence of Synpo caused loss of stress fibers, increased the number and size of focal adhesions, and impaired cell migration. Furthermore, loss of Synpo led to decreased RhoA activity and increased Rac1 activation. CONCLUSIONS In contrast to previous findings, podocytes can function normally in vivo in the absence of any Synpo isoform. Synpo plays a protective role in the context of podocyte injury through its involvement in actin reorganization and focal adhesion dynamics.
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Affiliation(s)
- Liang Ning
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Hani Y Suleiman
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
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24
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Kaverina NV, Eng DG, Miner JH, Pippin JW, Shankland SJ. Parietal epithelial cell differentiation to a podocyte fate in the aged mouse kidney. Aging (Albany NY) 2020; 12:17601-17624. [PMID: 32858527 PMCID: PMC7521511 DOI: 10.18632/aging.103788] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/29/2020] [Indexed: 01/24/2023]
Abstract
Healthy aging is typified by a progressive and absolute loss of podocytes over the lifespan of animals and humans. To test the hypothesis that a subset of glomerular parietal epithelial cell (PEC) progenitors transition to a podocyte fate with aging, dual reporter PEC-rtTA|LC1|tdTomato|Nphs1-FLPo|FRT-EGFP mice were generated. PECs were inducibly labeled with a tdTomato reporter, and podocytes were constitutively labeled with an EGFP reporter. With advancing age (14 and 24 months) glomeruli in the juxta-medullary cortex (JMC) were more severely injured than those in the outer cortex (OC). In aged mice (24m), injured glomeruli with lower podocyte number (41% decrease), showed more PEC migration and differentiation to a podocyte fate than mildly injured or healthy glomeruli. PECs differentiated to a podocyte fate had ultrastructural features of podocytes and co-expressed the podocyte markers podocin, nephrin, p57 and VEGF164, but not markers of mesangial (Perlecan) or endothelial (ERG) cells. PECs differentiated to a podocyte fate did not express CD44, a marker of PEC activation. Taken together, we demonstrate that a subpopulation of PECs differentiate to a podocyte fate predominantly in injured glomeruli in mice of advanced age.
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Affiliation(s)
| | - Diana G. Eng
- Division of Nephrology, University of Washington, Seattle, WA 98195, USA
| | - Jeffrey H. Miner
- Division of Nephrology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Jeffrey W. Pippin
- Division of Nephrology, University of Washington, Seattle, WA 98195, USA
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25
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Randles MJ, Lausecker F, Humphries JD, Byron A, Clark SJ, Miner JH, Zent R, Humphries MJ, Lennon R. Basement membrane ligands initiate distinct signalling networks to direct cell shape. Matrix Biol 2020; 90:61-78. [PMID: 32147508 PMCID: PMC7327512 DOI: 10.1016/j.matbio.2020.02.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 02/29/2020] [Accepted: 02/29/2020] [Indexed: 01/09/2023]
Abstract
Cells have evolved mechanisms to sense the composition of their adhesive microenvironment. Although much is known about general mechanisms employed by adhesion receptors to relay signals between the extracellular environment and the cytoskeleton, the nuances of ligand-specific signalling remain undefined. Here, we investigated how glomerular podocytes, and four other basement membrane-associated cell types, respond morphologically to different basement membrane ligands. We defined the composition of the respective adhesion complexes using mass spectrometry-based proteomics. On type IV collagen, all epithelial cell types adopted a round morphology, with a single lamellipodium and large adhesion complexes rich in actin-binding proteins. On laminin (511 or 521), all cell types attached to a similar degree but were polygonal in shape with small adhesion complexes enriched in endocytic and microtubule-binding proteins. Consistent with their distinctive morphologies, cells on type IV collagen exhibited high Rac1 activity, while those on laminin had elevated PKCα. Perturbation of PKCα was able to interchange morphology consistent with a key role for this pathway in matrix ligand-specific signalling. Therefore, this study defines the switchable basement membrane adhesome and highlights two key signalling pathways within the systems that determine distinct cell morphologies. Proteomic data are availableviaProteomeXchange with identifier PXD017913.
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Affiliation(s)
- Michael J Randles
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Franziska Lausecker
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Jonathan D Humphries
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Adam Byron
- Cancer Research UK Edinburgh Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Simon J Clark
- Universitäts-Augenklinik Tübingen, Eberhard Karls University of Tübingen, Germany; The Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology Medicine and Health, The University of Manchester, Manchester, UK
| | - Jeffrey H Miner
- Renal Division, Washington University School of Medicine, Saint Louis, MO, USA
| | - Roy Zent
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Martin J Humphries
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK; Department of Paediatric Nephrology, Royal Manchester Children's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK.
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26
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He C, Song W, Weston TA, Tran C, Kurtz I, Zuckerman JE, Guagliardo P, Miner JH, Ivanov SV, Bougoure J, Hudson BG, Colon S, Voziyan PA, Bhave G, Fong LG, Young SG, Jiang H. Peroxidasin-mediated bromine enrichment of basement membranes. Proc Natl Acad Sci U S A 2020; 117:15827-15836. [PMID: 32571911 PMCID: PMC7354931 DOI: 10.1073/pnas.2007749117] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Bromine and peroxidasin (an extracellular peroxidase) are essential for generating sulfilimine cross-links between a methionine and a hydroxylysine within collagen IV, a basement membrane protein. The sulfilimine cross-links increase the structural integrity of basement membranes. The formation of sulfilimine cross-links depends on the ability of peroxidasin to use bromide and hydrogen peroxide substrates to produce hypobromous acid (HOBr). Once a sulfilimine cross-link is created, bromide is released into the extracellular space and becomes available for reutilization. Whether the HOBr generated by peroxidasin is used very selectively for creating sulfilimine cross-links or whether it also causes oxidative damage to bystander molecules (e.g., generating bromotyrosine residues in basement membrane proteins) is unclear. To examine this issue, we used nanoscale secondary ion mass spectrometry (NanoSIMS) imaging to define the distribution of bromine in mammalian tissues. We observed striking enrichment of bromine (79Br, 81Br) in basement membranes of normal human and mouse kidneys. In peroxidasin knockout mice, bromine enrichment of basement membranes of kidneys was reduced by ∼85%. Proteomic studies revealed bromination of tyrosine-1485 in the NC1 domain of α2 collagen IV from kidneys of wild-type mice; the same tyrosine was brominated in collagen IV from human kidney. Bromination of tyrosine-1485 was reduced by >90% in kidneys of peroxidasin knockout mice. Thus, in addition to promoting sulfilimine cross-links in collagen IV, peroxidasin can also brominate a bystander tyrosine. Also, the fact that bromine enrichment is largely confined to basement membranes implies that peroxidasin activity is largely restricted to basement membranes in mammalian tissues.
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Affiliation(s)
- Cuiwen He
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Wenxin Song
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Thomas A Weston
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Caitlyn Tran
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Ira Kurtz
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Jonathan E Zuckerman
- Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA 90095
| | - Paul Guagliardo
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, 6009 Perth, Australia
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, MO 63110
| | - Sergey V Ivanov
- Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212
- Division of Nephrology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Jeremy Bougoure
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, 6009 Perth, Australia
| | - Billy G Hudson
- Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212
- Division of Nephrology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232
- Vanderbilt Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN 37232
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232
| | - Selene Colon
- Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212
- Division of Nephrology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37212
| | - Paul A Voziyan
- Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212
- Division of Nephrology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Gautam Bhave
- Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212
- Division of Nephrology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37212
- Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Loren G Fong
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Stephen G Young
- Department of Medicine, University of California, Los Angeles, CA 90095;
- Department of Human Genetics, University of California, Los Angeles, CA 90095
| | - Haibo Jiang
- School of Molecular Sciences, University of Western Australia, 6009 Perth, Australia;
- Department of Chemistry, The University of Hong Kong, Hong Kong, China
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27
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Weinstock BA, Feldman DL, Fornoni A, Gross O, Kashtan CE, Lagas S, Lennon R, Miner JH, Rheault MN, Simon JF. Clinical trial recommendations for potential Alport syndrome therapies. Kidney Int 2020; 97:1109-1116. [PMID: 32386680 PMCID: PMC7614298 DOI: 10.1016/j.kint.2020.02.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 02/04/2020] [Accepted: 02/12/2020] [Indexed: 12/26/2022]
Abstract
Alport syndrome is experiencing a remarkable increase in preclinical investigations. To proactively address the needs of the Alport syndrome community, as well as offer clarity for future clinical research sponsors, the Alport Syndrome Foundation hosted a workshop to generate consensus recommendations for prospective trials for conventional drugs. Opinions of key stakeholders were carefully considered, including those of the biopharmaceutical industry representatives, academic researchers, clinicians, regulatory agency representatives, and-most critically-patients with Alport syndrome. Recommendations were established for preclinical researchers, the use and selection of biomarkers, standards of care, clinical trial designs, trial eligibility criteria and outcomes, pediatric trial considerations, and considerations for patient engagement, recruitment, and treatment. This paper outlines their recommendations.
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Affiliation(s)
| | | | - Alessia Fornoni
- Katz Family Division of Nephrology and Hypertension, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Oliver Gross
- Department of Nephrology and Rheumatology, Universitätsmedizin Göttingen, Göttingen, Germany
| | - Clifford E Kashtan
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Sharon Lagas
- Alport Syndrome Foundation, Phoenix, Arizona, USA
| | - Rachel Lennon
- Division of Cell Matrix Biology & Regenerative Medicine, University of Manchester, Manchester, England, UK.
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Michelle N Rheault
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - James F Simon
- Department of Nephrology and Hypertension, The Cleveland Clinic, Cleveland, Ohio, USA
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28
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Affiliation(s)
- Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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29
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Tahoun M, Chandler JC, Ashton E, Haston S, Hannan A, Kim JS, D’Arco F, Bockenhauer D, Anderson G, Lin MH, Marzouk S, Saied MH, Miner JH, Dattani MT, Waters AM. Mutations in LAMB2 Are Associated With Albuminuria and Optic Nerve Hypoplasia With Hypopituitarism. J Clin Endocrinol Metab 2020; 105:5643661. [PMID: 31769495 PMCID: PMC7048679 DOI: 10.1210/clinem/dgz216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 11/25/2019] [Indexed: 01/15/2023]
Abstract
CONTEXT Mutations in LAMB2, encoding the basement membrane protein, laminin β2, are associated with an autosomal recessive disorder characterized by congenital nephrotic syndrome, ocular abnormalities, and neurodevelopmental delay (Pierson syndrome). CASE DESCRIPTION This report describes a 12-year-old boy with short stature, visual impairment, and developmental delay who presented with macroscopic hematuria and albuminuria. He had isolated growth hormone deficiency, optic nerve hypoplasia, and a small anterior pituitary with corpus callosum dysgenesis on his cranial magnetic resonance imaging, thereby supporting a diagnosis of optic nerve hypoplasia syndrome. Renal histopathology revealed focal segmental glomerulosclerosis. Using next-generation sequencing on a targeted gene panel for steroid-resistant nephrotic syndrome, compound heterozygous missense mutations were identified in LAMB2 (c.737G>A p.Arg246Gln, c.3982G>C p.Gly1328Arg). Immunohistochemical analysis revealed reduced glomerular laminin β2 expression compared to control kidney and a thin basement membrane on electron microscopy. Laminin β2 is expressed during pituitary development and Lamb2-/- mice exhibit stunted growth, abnormal neural retinae, and here we show, abnormal parenchyma of the anterior pituitary gland. CONCLUSION We propose that patients with genetically undefined optic nerve hypoplasia syndrome should be screened for albuminuria and, if present, screened for mutations in LAMB2.
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Affiliation(s)
- Mona Tahoun
- Clinical and Chemical Pathology Department, Faculty of Medicine, Alexandria University, Egypt
| | - Jennifer C Chandler
- UCL Great Ormond Street Institute of Child Health, University College London, UK
| | - Emma Ashton
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Scott Haston
- UCL Great Ormond Street Institute of Child Health, University College London, UK
| | - Athia Hannan
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Ji Soo Kim
- UCL Great Ormond Street Institute of Child Health, University College London, UK
| | - Felipe D’Arco
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - D Bockenhauer
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - G Anderson
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - Salah Marzouk
- Clinical and Chemical Pathology Department, Faculty of Medicine, Alexandria University, Egypt
| | - Marwa H Saied
- Clinical and Chemical Pathology Department, Faculty of Medicine, Alexandria University, Egypt
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - Mehul T Dattani
- UCL Great Ormond Street Institute of Child Health, University College London, UK
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Aoife M Waters
- UCL Great Ormond Street Institute of Child Health, University College London, UK
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
- Correspondence: Aoife Waters, MB, BAO, MSc, PhD, FRCPCH, Programme of Developmental Biology of Birth Defects, UCL Great Ormond Street Institute of Child Health, London WC1N 1EH, UK; Consultant Paediatric Nephrologist, Great Ormond Street Hospital NHS Foundation Trust, London, UK. E-mail: ;
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Funk SD, Bayer RH, McKee KK, Okada K, Nishimune H, Yurchenco PD, Miner JH. A deletion in the N-terminal polymerizing domain of laminin β2 is a new mouse model of chronic nephrotic syndrome. Kidney Int 2020; 98:133-146. [PMID: 32456966 DOI: 10.1016/j.kint.2020.01.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 01/14/2020] [Accepted: 01/21/2020] [Indexed: 10/25/2022]
Abstract
The importance of the glomerular basement membrane (GBM) in glomerular filtration is underscored by the manifestations of Alport and Pierson syndromes, caused by defects in type IV collagen α3α4α5 and the laminin β2 chain, respectively. Lamb2 null mice, which model the most severe form of Pierson syndrome, exhibit proteinuria prior to podocyte foot process effacement and are therefore useful for studying GBM permselectivity. We hypothesize that some LAMB2 missense mutations that cause mild forms of Pierson syndrome induce GBM destabilization with delayed effects on podocytes. While generating a CRISPR/Cas9-mediated analogue of a human LAMB2 missense mutation in mice, we identified a 44-amino acid deletion (LAMB2-Del44) within the laminin N-terminal domain, a domain mediating laminin polymerization. Laminin heterotrimers containing LAMB2-Del44 exhibited a 90% reduction in polymerization in vitro that was partially rescued by type IV collagen and nidogen. Del44 mice showed albuminuria at 1.8-6.0 g/g creatinine (ACR) at one to two months, plateauing at an average 200 g/g ACR at 3.7 months, when GBM thickening and hallmarks of nephrotic syndrome were first observed. Despite the massive albuminuria, some Del44 mice survived for up to 15 months. Blood urea nitrogen was modestly elevated at seven-nine months. Eight to nine-month-old Del44 mice exhibited glomerulosclerosis and interstitial fibrosis. Similar to Lamb2-/- mice, proteinuria preceded foot process effacement. Foot processes were widened but not effaced at one-two months despite the high ACRs. At three months some individual foot processes were still observed amid widespread effacement. Thus, our chronic model of nephrotic syndrome may prove useful to study filtration mechanisms, long-term proteinuria with preserved kidney function, and to test therapeutics.
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Affiliation(s)
- Steven D Funk
- Department of Internal Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA
| | - Raymond H Bayer
- Department of Internal Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA
| | - Kazushi Okada
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA
| | - Hiroshi Nishimune
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA
| | - Jeffrey H Miner
- Department of Internal Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA.
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31
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Lin MH, Pope BD, Sasaki T, Keeley DP, Sherwood DR, Miner JH. Mammalian hemicentin 1 is assembled into tracks in the extracellular matrix of multiple tissues. Dev Dyn 2020; 249:775-788. [PMID: 32035013 DOI: 10.1002/dvdy.159] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/20/2020] [Accepted: 01/31/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Hemicentins (HMCNs) are a family of extracellular matrix proteins first identified in Caenorhabditis elegans, with two orthologs (HMCN1 and 2) in vertebrates. In worms, HMCN is deposited at specific sites where it forms long, fine tracks that link two tissues by connecting adjacent basement membranes (BMs). By generating CRISPR/Cas9-mediated Hmcn1 and Hmcn2 knockout mice, we tested the hypothesis that HMCNs perform similar functions in mammals. RESULTS Hmcn1 -/- mice were viable and fertile. Using new, knockout mouse-validated HMCN1 antibodies, HMCN1 was detected in wild-type mice as fine tracks along the BM of hair and whisker follicles, in the sclera of the eyes, and in the lumen of some lymphoid conduits. It was also observed in the mesangial matrix of the kidney glomerulus. However, HMCN1 deficiency did not affect the functions of these tissues, including adherence of coat hairs and whiskers, the sieving function of lymphoid conduits, or the immune response to injected antigens. HMCN2 deficiency did not lead to any discernible phenotypes on its own or when combined with HMCN1 deficiency. CONCLUSION That Hmcn1 -/- , Hmcn2 -/- , and Hmcn1/2 double knockout mice did not display any overt phenotypes implicates compensation by other members of the fibulin family.
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Affiliation(s)
- Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Bill D Pope
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Takako Sasaki
- Department of Biochemistry II, Oita University, Oita, Japan
| | - Daniel P Keeley
- Department of Biology, Regeneration Next, Duke University, Durham, North Carolina, USA
| | - David R Sherwood
- Department of Biology, Regeneration Next, Duke University, Durham, North Carolina, USA
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA.,Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
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32
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Rheault MN, Savige J, Randles MJ, Weinstock A, Stepney M, Turner AN, Parziale G, Gross O, Flinter FA, Miner JH, Lagas S, Gear S, Lennon R. The importance of clinician, patient and researcher collaborations in Alport syndrome. Pediatr Nephrol 2020; 35:733-742. [PMID: 31044288 PMCID: PMC7096363 DOI: 10.1007/s00467-019-04241-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 03/15/2019] [Indexed: 12/19/2022]
Abstract
Alport syndrome is caused by mutations in the genes COL4A3, COL4A4 or COL4A5 and is characterised by progressive glomerular disease, sensorineural hearing loss and ocular defects. Occurring in less than 1:5000, Alport syndrome is a rare genetic disorder but still accounts for > 1% of the prevalent population receiving renal replacement therapy. There is also increasing awareness about the risk of chronic kidney disease in individuals with heterozygous mutations in Alport syndrome genes. The mainstay of current therapy is the use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, yet potential new therapies are now entering clinical trials. The 2017 International Workshop on Alport Syndrome in Glasgow was a pre-conference workshop ahead of the 50th anniversary meeting of the European Society for Pediatric Nephrology. It focussed on updates in clinical practice, genetics and basic science and also incorporated patient perspectives. More than 80 international experts including clinicians, geneticists, researchers from academia and industry, and patient representatives took part in panel discussions and breakout groups. This report summarises the workshop proceedings and the relevant contemporary literature. It highlights the unique clinician, patient and researcher collaborations achieved by regular engagement between the groups.
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Affiliation(s)
- Michelle N. Rheault
- Department of Pediatrics, University of Minnesota Masonic Children’s Hospital, Minneapolis, MN USA
| | - Judith Savige
- Department of Medicine, Royal Melbourne Hospital, Victoria, Australia
| | - Michael J. Randles
- Wellcome Centre for Cell-Matrix Research, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
| | | | - Melissa Stepney
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - A Neil Turner
- Renal Medicine, Royal Infirmary, University of Edinburgh, Edinburgh, UK
| | | | - Oliver Gross
- Clinic of Nephrology and Rheumatology, University Medicine Goettingen, Goettingen, Germany
| | - Frances A Flinter
- Department of Clinical Genetics, Guy’s & St Thomas’ NHS Foundation Trust, London, UK
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St Louis, MO USA
| | | | | | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK. .,Department of Paediatric Nephrology, Royal Manchester Children's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK.
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33
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Delitsikou V, Jarad G, Rajaram RD, Ino F, Rutkowski JM, Chen CD, Santos CXC, Scherer PE, Abraham CR, Shah AM, Feraille E, Miner JH, de Seigneux S. Klotho regulation by albuminuria is dependent on ATF3 and endoplasmic reticulum stress. FASEB J 2019; 34:2087-2104. [PMID: 31907991 DOI: 10.1096/fj.201900893r] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 10/31/2019] [Accepted: 11/13/2019] [Indexed: 12/11/2022]
Abstract
Proteinuria is associated with renal function decline and cardiovascular mortality. This association may be attributed in part to alterations of Klotho expression induced by albuminuria, yet the underlying mechanisms are unclear. The presence of albumin decreased Klotho expression in the POD-ATTAC mouse model of proteinuric kidney disease as well as in kidney epithelial cell lines. This downregulation was related to both decreased Klotho transcription and diminished protein half-life, whereas cleavage by ADAM proteases was not modified. The regulation was albumin specific since it was neither observed in the analbuminemic Col4α3-/- Alport mice nor induced by exposure of kidney epithelial cells to purified immunoglobulins. Albumin induced features of ER stress in renal tubular cells with ATF3/ATF4 activation. ATF3 and ATF4 induction downregulated Klotho through altered transcription mediated by their binding on the Klotho promoter. Inhibiting ER stress with 4-PBA decreased the effect of albumin on Klotho protein levels without altering mRNA levels, thus mainly abrogating the increased protein degradation. Taken together, albuminuria decreases Klotho expression through increased protein degradation and decreased transcription mediated by ER stress induction. This implies that modulating ER stress may improve proteinuria-induced alterations of Klotho expression, and hence renal and extrarenal complications associated with Klotho loss.
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Affiliation(s)
- Vasiliki Delitsikou
- Department of Cell Physiology and Metabolism, Faculty of Medicine, CMU, University of Geneva, Geneva, Switzerland.,Laboratory of Nephrology, Department of Internal Medicine Specialties, HUG, Geneva, Switzerland
| | - George Jarad
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Renuga Devi Rajaram
- Department of Cell Physiology and Metabolism, Faculty of Medicine, CMU, University of Geneva, Geneva, Switzerland.,Laboratory of Nephrology, Department of Internal Medicine Specialties, HUG, Geneva, Switzerland
| | - Frédérique Ino
- Department of Cell Physiology and Metabolism, Faculty of Medicine, CMU, University of Geneva, Geneva, Switzerland.,Laboratory of Nephrology, Department of Internal Medicine Specialties, HUG, Geneva, Switzerland
| | - Joseph M Rutkowski
- Touchstone Diabetes Centre, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas.,Department of Medical Physiology, Texas A&M College of Medicine, College Station, Texas
| | - Ci-Di Chen
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts
| | - Celio X C Santos
- King's College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine & Sciences, London, UK
| | - Philipp E Scherer
- Touchstone Diabetes Centre, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Carmela R Abraham
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts
| | - Ajay M Shah
- King's College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine & Sciences, London, UK
| | - Eric Feraille
- Department of Cell Physiology and Metabolism, Faculty of Medicine, CMU, University of Geneva, Geneva, Switzerland
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Sophie de Seigneux
- Department of Cell Physiology and Metabolism, Faculty of Medicine, CMU, University of Geneva, Geneva, Switzerland.,Laboratory of Nephrology, Department of Internal Medicine Specialties, HUG, Geneva, Switzerland
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Chan GC, Eng DG, Miner JH, Alpers CE, Hudkins K, Chang A, Pippin JW, Shankland SJ. Differential expression of parietal epithelial cell and podocyte extracellular matrix proteins in focal segmental glomerulosclerosis and diabetic nephropathy. Am J Physiol Renal Physiol 2019; 317:F1680-F1694. [PMID: 31630546 PMCID: PMC6962515 DOI: 10.1152/ajprenal.00266.2019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 01/03/2023] Open
Abstract
In healthy glomeruli, parietal epithelial cell (PEC)-derived extracellular matrix (ECM) proteins include laminin-β1, perlecan, and collagen type IV-α2 and podocyte-specific ECM proteins include laminin-β2, agrin, and collagen type IV-α4. This study aimed to define individual ECM protein isoform expression by PECs in both experimental and human focal segmental glomerulosclerosis (FSGS) and diabetic nephropathy (DN) and to determine if changes were CD44 dependent. In experimental FSGS induced with a cytotoxic podocyte antibody and in the BTBR ob/ob mouse model of DN, PEC-derived protein staining was significantly increased in PECs. Dual staining also showed de novo expression of the podocyte-specific ECM proteins laminin-β2 and agrin in PECs. Similar findings were observed in biopsies from patients with FSGS and DN. Increases in individual ECM proteins colocalized with CD44 in PECs in disease. To determine the role of CD44, FSGS was induced in CD44-/- and CD44+/+ mice. PEC staining for perlecan, collagen type IV-α2, laminin-β2, and agrin were significantly lower in diseased CD44-/- mice compared with diseased CD44+/+ mice. These results show that in experimental and human FSGS and DN, PECs typically in an activated state, produce both PEC-derived and podocyte-specific ECM protein isoforms, and that the majority of these changes were dependent on CD44.
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Affiliation(s)
- Gek Cher Chan
- Division of Nephrology, University of Washington, Seattle, Washington
- Division of Nephrology, National University Hospital, Singapore
| | - Diana G Eng
- Division of Nephrology, University of Washington, Seattle, Washington
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington
| | - Kelly Hudkins
- Department of Pathology, University of Washington, Seattle, Washington
| | - Anthony Chang
- Department of Pathology, University of Chicago, Chicago, Illinois
| | - Jeffrey W Pippin
- Division of Nephrology, University of Washington, Seattle, Washington
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35
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Jayasinghe RG, Cao S, Gao Q, Wendl MC, Vo NS, Reynolds SM, Zhao Y, Climente-González H, Chai S, Wang F, Varghese R, Huang M, Liang WW, Wyczalkowski MA, Sengupta S, Li Z, Payne SH, Fenyö D, Miner JH, Walter MJ, Vincent B, Eyras E, Chen K, Shmulevich I, Chen F, Ding L. Systematic Analysis of Splice-Site-Creating Mutations in Cancer. Cell Rep 2019; 23:270-281.e3. [PMID: 29617666 PMCID: PMC6055527 DOI: 10.1016/j.celrep.2018.03.052] [Citation(s) in RCA: 144] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 02/21/2018] [Accepted: 03/13/2018] [Indexed: 12/31/2022] Open
Abstract
For the past decade, cancer genomic studies have focused on mutations leading to splice-site disruption, overlooking those having splice-creating potential. Here, we applied a bioinformatic tool, MiSplice, for the large-scale discovery of splice-site-creating mutations (SCMs) across 8,656 TCGA tumors. We report 1,964 originally mis-annotated mutations having clear evidence of creating alternative splice junctions. TP53 and GATA3 have 26 and 18 SCMs, respectively, and ATRX has 5 from lower-grade gliomas. Mutations in 11 genes, including PARP1, BRCA1, and BAP1, were experimentally validated for splice-site-creating function. Notably, we found that neoantigens induced by SCMs are likely several folds more immunogenic compared to missense mutations, exemplified by the recurrent GATA3 SCM. Further, high expression of PD-1 and PD-L1 was observed in tumors with SCMs, suggesting candidates for immune blockade therapy. Our work highlights the importance of integrating DNA and RNA data for understanding the functional and the clinical implications of mutations in human diseases.
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Affiliation(s)
- Reyka G Jayasinghe
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Song Cao
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Qingsong Gao
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Michael C Wendl
- McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Genetics, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Mathematics, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Nam Sy Vo
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Yanyan Zhao
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Héctor Climente-González
- Institut Curie, 75248 Paris Cedex, France; MINES ParisTech, PSL-Research University, CBIO-Centre for Computational Biology, 77300 Fontainebleau, France; INSERM U900, 75248 Paris Cedex, France
| | - Shengjie Chai
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Curriculum in Bioinformatics and Computational Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Fang Wang
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Rajees Varghese
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; Division of Nephrology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Mo Huang
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA
| | - Wen-Wei Liang
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Matthew A Wyczalkowski
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Sohini Sengupta
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Zhi Li
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA; Institute for Systems Genetics, New York University School of Medicine, New York, NY 10016, USA
| | - Samuel H Payne
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - David Fenyö
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA; Institute for Systems Genetics, New York University School of Medicine, New York, NY 10016, USA
| | - Jeffrey H Miner
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; Division of Nephrology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Matthew J Walter
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO 63110, USA
| | | | - Benjamin Vincent
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Curriculum in Bioinformatics and Computational Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Eduardo Eyras
- Catalan Institution of Research and Advanced Studies (ICREA), 08010 Barcelona, Spain; Computational RNA Biology Group, Pompeu Fabra University (UPF), 08003 Barcelona, Spain
| | - Ken Chen
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Feng Chen
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; Division of Nephrology, Washington University in St. Louis, St. Louis, MO 63110, USA.
| | - Li Ding
- Department of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA; McDonnell Genome Institute, Washington University in St. Louis, St. Louis, MO 63108, USA; Division of Oncology, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Genetics, Washington University in St. Louis, St. Louis, MO 63110, USA; Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO 63110, USA.
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Kaverina NV, Eng DG, Freedman BS, Kutz JN, Chozinski TJ, Vaughan JC, Miner JH, Pippin JW, Shankland SJ. Dual lineage tracing shows that glomerular parietal epithelial cells can transdifferentiate toward the adult podocyte fate. Kidney Int 2019; 96:597-611. [PMID: 31200942 PMCID: PMC7008116 DOI: 10.1016/j.kint.2019.03.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 03/11/2019] [Accepted: 03/12/2019] [Indexed: 12/12/2022]
Abstract
Podocytes are differentiated post-mitotic cells that cannot replace themselves after injury. Glomerular parietal epithelial cells are proposed to be podocyte progenitors. To test whether a subset of parietal epithelial cells transdifferentiate to a podocyte fate, dual reporter PEC-rtTA|LC1|tdTomato|Nphs1-FLPo|FRT-EGFP mice, named PEC-PODO, were generated. Doxycycline administration permanently labeled parietal epithelial cells with tdTomato reporter (red), and upon doxycycline removal, the parietal epithelial cells (PECs) cannot label further. Despite the presence or absence of doxycycline, podocytes cannot label with tdTomato, but are constitutively labeled with an enhanced green fluorescent protein (EGFP) reporter (green). Only activation of the Nphs1-FLPo transgene by labeled parietal epithelial cells can generate a yellow color. At day 28 of experimental focal segmental glomerulosclerosis, podocyte density was 20% lower in 20% of glomeruli. At day 56 of experimental focal segmental glomerulosclerosis, podocyte density was 18% lower in 17% of glomeruli. TdTomato+ parietal epithelial cells were restricted to Bowman's capsule in healthy mice. However, by days 28 and 56 of experimental disease, two-thirds of tdTomato+ parietal epithelial cells within glomerular tufts were yellow in color. These cells co-expressed the podocyte markers podocin, nephrin, p57 and VEGF164, but not markers of endothelial (ERG) or mesangial (Perlecan) cells. Expansion microscopy showed primary, secondary and minor processes in tdTomato+EGFP+ cells in glomerular tufts. Thus, our studies provide strong evidence that parietal epithelial cells serve as a source of new podocytes in adult mice.
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Affiliation(s)
- Natalya V Kaverina
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Diana G Eng
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | | | - J Nathan Kutz
- Department of Applied Mathematics, University of Washington, Seattle, Washington, USA
| | - Tyler J Chozinski
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Joshua C Vaughan
- Department of Chemistry, University of Washington, Seattle, Washington, USA; Department of Physiology and Biophysics, University of Washington, Seattle, Washington, USA
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St Louis, Missouri, USA
| | - Jeffrey W Pippin
- Division of Nephrology, University of Washington, Seattle, Washington, USA
| | - Stuart J Shankland
- Division of Nephrology, University of Washington, Seattle, Washington, USA.
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Funk SD, Bayer RH, Miner JH. Endothelial cell-specific collagen type IV-α 3 expression does not rescue Alport syndrome in Col4a3 -/- mice. Am J Physiol Renal Physiol 2019; 316:F830-F837. [PMID: 30724107 PMCID: PMC6580247 DOI: 10.1152/ajprenal.00556.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 01/23/2019] [Accepted: 02/04/2019] [Indexed: 01/15/2023] Open
Abstract
The glomerular basement membrane (GBM) is a critical component of the kidney's blood filtration barrier. Alport syndrome, a hereditary disease leading to kidney failure, is caused by the loss or dysfunction of the GBM's major collagen type IV (COL4) isoform α3α4α5. The constituent COL4 α-chains assemble into heterotrimers in the endoplasmic reticulum before secretion into the extracellular space. If any one of the α3-, α4-, or α5-chains is lost due to mutation of one of the genes, then the entire heterotrimer is lost. Patients with Alport syndrome typically have mutations in the X-linked COL4A5 gene or uncommonly have the autosomal recessive form of the disease due to COL4A3 or COL4A4 mutations. Treatment for Alport syndrome is currently limited to angiotensin-converting enzyme inhibition or angiotensin receptor blockers. Experimental approaches in Alport mice have demonstrated that induced expression of COL4A3, either widely or specifically in podocytes of Col4a3-/- mice, can abrogate disease progression even after establishment of the abnormal GBM. While targeting podocytes in vivo for gene therapy is a significant challenge, the more accessible glomerular endothelium could be amenable for mutant gene repair. In the present study, we expressed COL4A3 in Col4a3-/- Alport mice using an endothelial cell-specific inducible transgenic system, but collagen-α3α4α5(IV) was not detected in the GBM or elsewhere, and the Alport phenotype was not rescued. Our results suggest that endothelial cells do not express the Col4a3/a4/a5 genes and should not be viewed as a target for gene therapy.
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Affiliation(s)
- Steven D Funk
- Department of Medicine, Division of Nephrology, Washington University School of Medicine , St. Louis, Missouri
| | - Raymond H Bayer
- Department of Medicine, Division of Nephrology, Washington University School of Medicine , St. Louis, Missouri
| | - Jeffrey H Miner
- Department of Medicine, Division of Nephrology, Washington University School of Medicine , St. Louis, Missouri
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Nirwane A, Johnson J, Nguyen B, Miner JH, Yao Y. Mural cell-derived laminin-α5 plays a detrimental role in ischemic stroke. Acta Neuropathol Commun 2019; 7:23. [PMID: 30777135 PMCID: PMC6378751 DOI: 10.1186/s40478-019-0676-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 02/10/2019] [Indexed: 12/12/2022] Open
Abstract
At the blood-brain barrier (BBB), laminin-α5 is predominantly synthesized by endothelial cells and mural cells. Endothelial laminin-α5 is dispensable for BBB maintenance under homeostatic conditions but inhibits inflammatory cell extravasation in pathological conditions. Whether mural cell-derived laminin-α5 is involved in vascular integrity regulation, however, remains unknown. To answer this question, we generated transgenic mice with laminin-α5 deficiency in mural cells (α5-PKO). Under homeostatic conditions, no defects in BBB integrity and cerebral blood flow (CBF) were observed in α5-PKO mice, suggesting that mural cell-derived laminin-α5 is dispensable for BBB maintenance and CBF regulation under homeostatic conditions. After ischemia-reperfusion (MCAO) injury, however, α5-PKO mice displayed less severe neuronal injury, including reduced infarct volume, decreased neuronal death, and improved neurological function. In addition, α5-PKO mice also showed attenuated vascular damage (milder BBB disruption, reduced inflammatory cell infiltration, decreased brain edema, and diminished hemorrhagic transformation). Mechanistic studies revealed less severe tight junction protein (TJP) loss and pericyte coverage reduction in α5-PKO mice after ischemia-reperfusion injury, indicating that the attenuated ischemic injury in α5-PKO mice is possibly due to less severe vascular damage. These findings suggest that mural cell-derived laminin-α5 plays a detrimental role in ischemic stroke and that inhibiting its signaling may have a neuroprotective effect.
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Crumrine D, Khnykin D, Krieg P, Man MQ, Celli A, Mauro TM, Wakefield JS, Menon G, Mauldin E, Miner JH, Lin MH, Brash AR, Sprecher E, Radner FPW, Choate K, Roop D, Uchida Y, Gruber R, Schmuth M, Elias PM. Mutations in Recessive Congenital Ichthyoses Illuminate the Origin and Functions of the Corneocyte Lipid Envelope. J Invest Dermatol 2018; 139:760-768. [PMID: 30471252 DOI: 10.1016/j.jid.2018.11.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 10/25/2018] [Accepted: 11/07/2018] [Indexed: 12/26/2022]
Abstract
The corneocyte lipid envelope (CLE), a monolayer of ω-hydroxyceramides whose function(s) remain(s) uncertain, is absent in patients with autosomal recessive congenital ichthyoses with mutations in enzymes that regulate epidermal lipid synthesis. Secreted lipids fail to transform into lamellar membranes in certain autosomal recessive congenital ichthyosis epidermis, suggesting the CLE provides a scaffold for the extracellular lamellae. However, because cornified envelopes are attenuated in these autosomal recessive congenital ichthyoses, the CLE may also provide a scaffold for subjacent cornified envelope formation, evidenced by restoration of cornified envelopes after CLE rescue. We provide multiple lines of evidence that the CLE originates as lamellar body-limiting membranes fuse with the plasma membrane: (i) ABCA12 patients and Abca12-/- mice display normal CLEs; (ii) CLEs are normal in Netherton syndrome, despite destruction of secreted LB contents; (iii) CLEs are absent in VSP33B-negative patients; (iv) limiting membranes of lamellar bodies are defective in lipid-synthetic autosomal recessive congenital ichthyoses; and (v) lipoxygenases, lipase activity, and LIPN co-localize within putative lamellar bodies.
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Affiliation(s)
- Debra Crumrine
- Dermatology Service, Veterans Affairs Medical Center, San Francisco, California, USA; Department of Dermatology, University of California-San Francisco, San Francisco, California, USA
| | - Denis Khnykin
- Department of Pathology, Oslo University Hospital, Oslo, Norway; Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Peter Krieg
- Molecular Diagnostics of Oncogenic Infections, German Cancer Research Center, Heidelberg, Germany
| | - Mao-Qiang Man
- Dermatology Service, Veterans Affairs Medical Center, San Francisco, California, USA; Department of Dermatology, University of California-San Francisco, San Francisco, California, USA
| | - Anna Celli
- Dermatology Service, Veterans Affairs Medical Center, San Francisco, California, USA; Department of Dermatology, University of California-San Francisco, San Francisco, California, USA
| | - Theodora M Mauro
- Dermatology Service, Veterans Affairs Medical Center, San Francisco, California, USA; Department of Dermatology, University of California-San Francisco, San Francisco, California, USA
| | - Joan S Wakefield
- Dermatology Service, Veterans Affairs Medical Center, San Francisco, California, USA; Department of Dermatology, University of California-San Francisco, San Francisco, California, USA
| | | | - Elizabeth Mauldin
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jeffrey H Miner
- Department of Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA
| | - Meei-Hua Lin
- Department of Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA
| | - Alan R Brash
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Eli Sprecher
- Department of Dermatology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Franz P W Radner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Keith Choate
- Departments of Dermatology and Genetics, Yale University, New Haven, Connecticut, USA
| | - Dennis Roop
- Department of Dermatology, University of Colorado, Denver, Colorado, USA
| | - Yoshikazu Uchida
- Dermatology Service, Veterans Affairs Medical Center, San Francisco, California, USA; Department of Dermatology, University of California-San Francisco, San Francisco, California, USA
| | - Robert Gruber
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Matthias Schmuth
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Peter M Elias
- Dermatology Service, Veterans Affairs Medical Center, San Francisco, California, USA; Department of Dermatology, University of California-San Francisco, San Francisco, California, USA.
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40
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Funk SD, Lin MH, Miner JH. Alport syndrome and Pierson syndrome: Diseases of the glomerular basement membrane. Matrix Biol 2018; 71-72:250-261. [PMID: 29673759 PMCID: PMC6146048 DOI: 10.1016/j.matbio.2018.04.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/13/2018] [Accepted: 04/13/2018] [Indexed: 12/17/2022]
Abstract
The glomerular basement membrane (GBM) is an important component of the kidney's glomerular filtration barrier. Like all basement membranes, the GBM contains type IV collagen, laminin, nidogen, and heparan sulfate proteoglycan. It is flanked by the podocytes and glomerular endothelial cells that both synthesize it and adhere to it. Mutations that affect the GBM's collagen α3α4α5(IV) components cause Alport syndrome (kidney disease with variable ear and eye defects) and its variants, including thin basement membrane nephropathy. Mutations in LAMB2 that impact the synthesis or function of laminin α5β2γ1 (LM-521) cause Pierson syndrome (congenital nephrotic syndrome with eye and neurological defects) and its less severe variants, including isolated congenital nephrotic syndrome. The very different types of kidney diseases that result from mutations in collagen IV vs. laminin are likely due to very different pathogenic mechanisms. A better understanding of these mechanisms should lead to targeted therapeutic approaches that can help people with these rare but important diseases.
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Affiliation(s)
- Steven D Funk
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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41
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Affiliation(s)
- William H Fissell
- Division of Nephrology and Hypertension, Vanderbilt University Medical Center, Nashville, Tennessee; and
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
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Luo W, Olaru F, Miner JH, Beck LH, van der Vlag J, Thurman JM, Borza DB. Alternative Pathway Is Essential for Glomerular Complement Activation and Proteinuria in a Mouse Model of Membranous Nephropathy. Front Immunol 2018; 9:1433. [PMID: 29988342 PMCID: PMC6023961 DOI: 10.3389/fimmu.2018.01433] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 06/11/2018] [Indexed: 01/15/2023] Open
Abstract
Membranous nephropathy is an immune kidney disease caused by IgG antibodies that form glomerular subepithelial immune complexes. Proteinuria is mediated by complement activation, as a result of podocyte injury by C5b-9, but the role of specific complement pathways is not known. Autoantibodies-mediating primary membranous nephropathy are predominantly of IgG4 subclass, which cannot activate the classical pathway. Histologic evidence from kidney biopsies suggests that the lectin and the alternative pathways may be activated in membranous nephropathy, but the pathogenic relevance of these pathways remains unclear. In this study, we evaluated the role of the alternative pathway in a mouse model of membranous nephropathy. After inducing the formation of subepithelial immune complexes, we found similar glomerular IgG deposition in wild-type mice and in factor B-null mice, which lack a functional alternative pathway. Unlike wild-type mice, mice lacking factor B did not develop albuminuria nor exhibit glomerular deposition of C3c and C5b-9. Albuminuria was also reduced but not completely abolished in C5-deficient mice. Our results provide the first direct evidence that the alternative pathway is necessary for pathogenic complement activation by glomerular subepithelial immune complexes and is, therefore, a key mediator of proteinuria in experimental membranous nephropathy. This knowledge is important for the rational design of new therapies for membranous nephropathy.
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Affiliation(s)
- Wentian Luo
- Division of Nephrology, Department of Medicine, Vanderbilt Medical Center, Nashville, TN, United States.,Vanderbilt Center for Kidney Disease, Vanderbilt Division of Nephrology, Nashville, TN, United States
| | - Florina Olaru
- Division of Nephrology, Department of Medicine, Vanderbilt Medical Center, Nashville, TN, United States.,Division of Nephrology, Department of Medicine, Vanderbilt Medical Center, Nashville, TN, United States
| | - Jeffrey H Miner
- Renal Division, Washington University School of Medicine, St. Louis, MO, United States
| | - Laurence H Beck
- Division of Nephrology, Boston University Medical Center, Boston, MA, United States
| | - Johan van der Vlag
- Department of Nephrology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Joshua M Thurman
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
| | - Dorin-Bogdan Borza
- Vanderbilt Center for Kidney Disease, Vanderbilt Division of Nephrology, Nashville, TN, United States.,Department of Microbiology, Immunology and Physiology, Meharry Medical College, Nashville, TN, United States
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Omar MH, Kerrisk Campbell M, Xiao X, Zhong Q, Brunken WJ, Miner JH, Greer CA, Koleske AJ. CNS Neurons Deposit Laminin α5 to Stabilize Synapses. Cell Rep 2018; 21:1281-1292. [PMID: 29091766 PMCID: PMC5776391 DOI: 10.1016/j.celrep.2017.10.028] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/21/2017] [Accepted: 10/08/2017] [Indexed: 11/28/2022] Open
Abstract
Synapses in the developing brain are structurally dynamic but become stable by early adulthood. We demonstrate here that an α5-subunit-containing laminin stabilizes synapses during this developmental transition. Hippocampal neurons deposit laminin α5 at synapses during adolescence as connections stabilize. Disruption of laminin α5 in neurons causes dramatic fluctuations in dendritic spine head size that can be rescued by exogenous α5-containing laminin. Conditional deletion of laminin α5 in vivo increases dendritic spine size and leads to an age-dependent loss of synapses accompanied by behavioral defects. Remaining synapses have larger postsynaptic densities and enhanced neurotransmission. Finally, we provide evidence that laminin α5 acts through an integrin α3β1-Abl2 kinase-p190RhoGAP signaling cascade and partners with laminin β2 to regulate dendritic spine density and behavior. Together, our results identify laminin α5 as a stabilizer of dendritic spines and synapses in the brain and elucidate key cellular and molecular mechanisms by which it acts.
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Affiliation(s)
- Mitchell H Omar
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Meghan Kerrisk Campbell
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Xiao Xiao
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Qiaonan Zhong
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06510, USA
| | - William J Brunken
- Department of Ophthalmology, Upstate Medical University, Syracuse, NY 13202, USA
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Charles A Greer
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA; Department of Neurosurgery, Yale University, New Haven, CT 06510, USA
| | - Anthony J Koleske
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06510, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA.
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Lin MH, Miller JB, Kikkawa Y, Suleiman HY, Tryggvason K, Hodges BL, Miner JH. Laminin-521 Protein Therapy for Glomerular Basement Membrane and Podocyte Abnormalities in a Model of Pierson Syndrome. J Am Soc Nephrol 2018; 29:1426-1436. [PMID: 29472414 PMCID: PMC5967757 DOI: 10.1681/asn.2017060690] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 01/14/2018] [Indexed: 12/22/2022] Open
Abstract
Background Laminin α5β2γ1 (LM-521) is a major component of the GBM. Mutations in LAMB2 that prevent LM-521 synthesis and/or secretion cause Pierson syndrome, a rare congenital nephrotic syndrome with diffuse mesangial sclerosis and ocular and neurologic defects. Because the GBM is uniquely accessible to plasma, which permeates endothelial cell fenestrae, we hypothesized that intravenous delivery of LM-521 could replace the missing LM-521 in the GBM of Lamb2 mutant mice and restore glomerular permselectivity.Methods We injected human LM-521 (hLM-521), a macromolecule of approximately 800 kD, into the retro-orbital sinus of Lamb2-/- pups daily. Deposition of hLM-521 into the GBM was investigated by fluorescence microscopy. We assayed the effects of hLM-521 on glomerular permselectivity by urinalysis and the effects on podocytes by desmin immunostaining and ultrastructural analysis of podocyte architecture.Results Injected hLM-521 rapidly and stably accumulated in the GBM of all glomeruli. Super-resolution imaging showed that hLM-521 accumulated in the correct orientation in the GBM, primarily on the endothelial aspect. Treatment with hLM-521 greatly reduced the expression of the podocyte injury marker desmin and attenuated the foot process effacement observed in untreated pups. Moreover, treatment with hLM-521 delayed the onset of proteinuria but did not prevent nephrotic syndrome, perhaps due to its absence from the podocyte aspect of the GBM.Conclusions These studies show that GBM composition and function can be altered in vivovia vascular delivery of even very large proteins, which may advance therapeutic options for patients with abnormal GBM composition, whether genetic or acquired.
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Affiliation(s)
- Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Joseph B Miller
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Yamato Kikkawa
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Karl Tryggvason
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden; and
| | | | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri;
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Germino EA, Miller JP, Diehl L, Swanson CJ, Durinck S, Modrusan Z, Miner JH, Shaw AS. Homozygous KSR1 deletion attenuates morbidity but does not prevent tumor development in a mouse model of RAS-driven pancreatic cancer. PLoS One 2018; 13:e0194998. [PMID: 29596465 PMCID: PMC5875795 DOI: 10.1371/journal.pone.0194998] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 03/14/2018] [Indexed: 01/04/2023] Open
Abstract
Given the frequency with which MAP kinase signaling is dysregulated in cancer, much effort has been focused on inhibiting RAS signaling for therapeutic benefit. KSR1, a pseudokinase that interacts with RAF, is a potential target; it was originally cloned in screens for suppressors of constitutively active RAS, and its deletion prevents RAS-mediated transformation of mouse embryonic fibroblasts. In this work, we used a genetically engineered mouse model of pancreatic cancer to assess whether KSR1 deletion would influence tumor development in the setting of oncogenic RAS. We found that Ksr1-/- mice on this background had a modest but significant improvement in all-cause morbidity compared to Ksr1+/+ and Ksr1+/- cohorts. Ksr1-/- mice, however, still developed tumors, and precursor pancreatic intraepithelial neoplastic (PanIN) lesions were detected within a similar timeframe compared to Ksr1+/+ mice. No significant differences in pERK expression or in proliferation were noted. RNA sequencing also did not reveal any unique genetic signature in Ksr1-/- tumors. Further studies will be needed to determine whether and in what settings KSR inhibition may be clinically useful.
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Affiliation(s)
- Elizabeth A. Germino
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Research Biology, Genentech, South San Francisco, California, United States of America
| | - Joseph P. Miller
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Lauri Diehl
- Department of Pathology, Genentech, South San Francisco, California, United States of America
| | - Carter J. Swanson
- Department of Research Biology, Genentech, South San Francisco, California, United States of America
| | - Steffen Durinck
- Department of Bioinformatics and Computational Biology, Genentech, South San Francisco, California, United States of America
- Department of Molecular Biology, Genentech, South San Francisco, California, United States of America
| | - Zora Modrusan
- Department of Molecular Biology, Genentech, South San Francisco, California, United States of America
| | - Jeffrey H. Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Andrey S. Shaw
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Research Biology, Genentech, South San Francisco, California, United States of America
- * E-mail:
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Brähler S, Zinselmeyer BH, Raju S, Nitschke M, Suleiman H, Saunders BT, Johnson MW, Böhner AMC, Viehmann SF, Theisen DJ, Kretzer NM, Briseño CG, Zaitsev K, Ornatsky O, Chang Q, Carrero JA, Kopp JB, Artyomov MN, Kurts C, Murphy KM, Miner JH, Shaw AS. Opposing Roles of Dendritic Cell Subsets in Experimental GN. J Am Soc Nephrol 2018; 29:138-154. [PMID: 29217759 PMCID: PMC5748909 DOI: 10.1681/asn.2017030270] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 09/15/2017] [Indexed: 01/08/2023] Open
Abstract
Dendritic cells (DCs) are thought to form a dendritic network across barrier surfaces and throughout organs, including the kidney, to perform an important sentinel function. However, previous studies of DC function used markers, such as CD11c or CX3CR1, that are not unique to DCs. Here, we evaluated the role of DCs in renal inflammation using a CD11c reporter mouse line and two mouse lines with DC-specific reporters, Zbtb46-GFP and Snx22-GFP. Multiphoton microscopy of kidney sections confirmed that most of the dendritically shaped CD11c+ cells forming a network throughout the renal interstitium expressed macrophage-specific markers. In contrast, DCs marked by Zbtb46-GFP or Snx22-GFP were less abundant, concentrated around blood vessels, and round in shape. We confirmed this pattern of localization using imaging mass cytometry. Motility measurements showed that resident macrophages were sessile, whereas DCs were motile before and after inflammation. Although uninflamed glomeruli rarely contained DCs, injury with nephrotoxic antibodies resulted in accumulation of ZBTB46 + cells in the periglomerular region. ZBTB46 identifies all classic DCs, which can be categorized into two functional subsets that express either CD103 or CD11b. Depletion of ZBTB46 + cells attenuated the antibody-induced kidney injury, whereas deficiency of the CD103+ subset accelerated injury through a mechanism that involved increased neutrophil infiltration. RNA sequencing 7 days after nephrotoxic antibody injection showed that CD11b+ DCs expressed the neutrophil-attracting cytokine CXCL2, whereas CD103+ DCs expressed high levels of several anti-inflammatory genes. These results provide new insights into the distinct functions of the two major DC subsets in glomerular inflammation.
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Affiliation(s)
- Sebastian Brähler
- Department of Pathology and Immunology
- Division of Nephrology, Department of Medicine, and
- Department II of Internal Medicine and
- Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | | | | | | | | | | | | | - Alexander M C Böhner
- Institute of Experimental Immunology, University Clinic of the Rheinische Friedrich Wilhelms Universität, Bonn, Germany
| | - Susanne F Viehmann
- Institute of Experimental Immunology, University Clinic of the Rheinische Friedrich Wilhelms Universität, Bonn, Germany
| | | | | | | | - Konstantin Zaitsev
- Computer Technologies Department, ITMO University, St. Petersburg, Russia
| | | | - Qing Chang
- Fluidigm Inc., Markham, Ontario, Canada; and
| | | | - Jeffrey B Kopp
- Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Maxim N Artyomov
- Department of Pathology and Immunology
- Computer Technologies Department, ITMO University, St. Petersburg, Russia
| | - Christian Kurts
- Institute of Experimental Immunology, University Clinic of the Rheinische Friedrich Wilhelms Universität, Bonn, Germany
| | - Kenneth M Murphy
- Department of Pathology and Immunology
- Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri
| | | | - Andrey S Shaw
- Research Biology, Genentech, South San Francisco, California;
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Funk SD, Bayer RH, Malone AF, McKee KK, Yurchenco PD, Miner JH. Pathogenicity of a Human Laminin β2 Mutation Revealed in Models of Alport Syndrome. J Am Soc Nephrol 2017; 29:949-960. [PMID: 29263159 DOI: 10.1681/asn.2017090997] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Accepted: 11/19/2017] [Indexed: 01/15/2023] Open
Abstract
Pierson syndrome is a congenital nephrotic syndrome with eye and neurologic defects caused by mutations in laminin β2 (LAMB2), a major component of the glomerular basement membrane (GBM). Pathogenic missense mutations in human LAMB2 cluster in or near the laminin amino-terminal (LN) domain, a domain required for extracellular polymerization of laminin trimers and basement membrane scaffolding. Here, we investigated an LN domain missense mutation, LAMB2-S80R, which was discovered in a patient with Pierson syndrome and unusually late onset of proteinuria. Biochemical data indicated that this mutation impairs laminin polymerization, which we hypothesized to be the cause of the patient's nephrotic syndrome. Testing this hypothesis in genetically altered mice showed that the corresponding amino acid change (LAMB2-S83R) alone is not pathogenic. However, expression of LAMB2-S83R significantly increased the rate of progression to kidney failure in a Col4a3-/- mouse model of autosomal recessive Alport syndrome and increased proteinuria in Col4a5+/- females that exhibit a mild form of X-linked Alport syndrome due to mosaic deposition of collagen α3α4α5(IV) in the GBM. Collectively, these data show the pathogenicity of LAMB2-S80R and provide the first evidence of genetic modification of Alport phenotypes by variation in another GBM component. This finding could help explain the wide range of Alport syndrome onset and severity observed in patients with Alport syndrome, even for family members who share the same COL4 mutation. Our results also show the complexities of using model organisms to investigate genetic variants suspected of being pathogenic in humans.
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Affiliation(s)
- Steven D Funk
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Raymond H Bayer
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Andrew F Malone
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
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Kim AH, Chung JJ, Akilesh S, Koziell A, Jain S, Hodgin JB, Miller MJ, Stappenbeck TS, Miner JH, Shaw AS. B cell-derived IL-4 acts on podocytes to induce proteinuria and foot process effacement. JCI Insight 2017; 2:81836. [PMID: 29093269 DOI: 10.1172/jci.insight.81836] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 10/05/2017] [Indexed: 12/13/2022] Open
Abstract
The efficacy of B cell depletion therapies in diseases such as nephrotic syndrome and rheumatoid arthritis suggests a broader role in B cells in human disease than previously recognized. In some of these diseases, such as the minimal change disease subtype of nephrotic syndrome, pathogenic antibodies and immune complexes are not involved. We hypothesized that B cells, activated in the kidney, might produce cytokines capable of directly inducing cell injury and proteinuria. To directly test our hypothesis, we targeted a model antigen to the kidney glomerulus and showed that transfer of antigen-specific B cells could induce glomerular injury and proteinuria. This effect was mediated by IL-4, as transfer of IL-4-deficient B cells did not induce proteinuria. Overexpression of IL-4 in mice was sufficient to induce kidney injury and proteinuria and could be attenuated by JAK kinase inhibitors. Since IL-4 is a specific activator of STAT6, we analyzed kidney biopsies and demonstrated STAT6 activation in up to 1 of 3 of minimal change disease patients, suggesting IL-4 or IL-13 exposure in these patients. These data suggest that the role of B cells in nephrotic syndrome could be mediated by cytokines.
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Affiliation(s)
- Alfred Hj Kim
- Division of Rheumatology, Department of Internal Medicine, and
| | - Jun-Jae Chung
- Division of Immunobiology, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Shreeram Akilesh
- Division of Immunobiology, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Ania Koziell
- Department of Experimental Immunobiology, Division of Transplantation Immunology and Mucosal Biology, King's College London and Department of Paediatric Nephrology, Evelina Children's Hospital, London, United Kingdom
| | - Sanjay Jain
- Renal Division, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jeffrey B Hodgin
- Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA
| | - Mark J Miller
- Division of Immunobiology, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Thaddeus S Stappenbeck
- Division of Immunobiology, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jeffrey H Miner
- Renal Division, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Andrey S Shaw
- Division of Immunobiology, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA.,Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri, USA
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49
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Tsuji K, Suleiman H, Miner JH, Daley JM, Capen DE, Păunescu TG, Lu HAJ. Ultrastructural Characterization of the Glomerulopathy in Alport Mice by Helium Ion Scanning Microscopy (HIM). Sci Rep 2017; 7:11696. [PMID: 28916834 PMCID: PMC5601433 DOI: 10.1038/s41598-017-12064-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 09/01/2017] [Indexed: 01/19/2023] Open
Abstract
The glomerulus exercises its filtration barrier function by establishing a complex filtration apparatus consisting of podocyte foot processes, glomerular basement membrane and endothelial cells. Disruption of any component of the glomerular filtration barrier leads to glomerular dysfunction, frequently manifested as proteinuria. Ultrastructural studies of the glomerulus by transmission electron microscopy (TEM) and conventional scanning electron microscopy (SEM) have been routinely used to identify and classify various glomerular diseases. Here we report the application of newly developed helium ion scanning microscopy (HIM) to examine the glomerulopathy in a Col4a3 mutant/Alport syndrome mouse model. Our study revealed unprecedented details of glomerular abnormalities in Col4a3 mutants including distorted podocyte cell bodies and disorganized primary processes. Strikingly, we observed abundant filamentous microprojections arising from podocyte cell bodies and processes, and presence of unique bridging processes that connect the primary processes and foot processes in Alport mice. Furthermore, we detected an altered glomerular endothelium with disrupted sub-endothelial integrity. More importantly, we were able to clearly visualize the complex, three-dimensional podocyte and endothelial interface by HIM. Our study demonstrates that HIM provides nanometer resolution to uncover and rediscover critical ultrastructural characteristics of the glomerulopathy in Col4a3 mutant mice.
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Affiliation(s)
- Kenji Tsuji
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Hani Suleiman
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.,Division of Nephrology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, MO, USA
| | - James M Daley
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Diane E Capen
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Teodor G Păunescu
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Hua A Jenny Lu
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA.
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50
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Bartlett CS, Scott RP, Carota IA, Wnuk ML, Kanwar YS, Miner JH, Quaggin SE. Glomerular mesangial cell recruitment and function require the co-receptor neuropilin-1. Am J Physiol Renal Physiol 2017; 313:F1232-F1242. [PMID: 28835419 DOI: 10.1152/ajprenal.00311.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/08/2017] [Accepted: 08/16/2017] [Indexed: 01/11/2023] Open
Abstract
Proteinuria has been reported in cancer patients receiving agents that target the transmembrane receptor neuropilin-1 (Nrp1) suggesting potential adverse effects on glomerular function. Here we show that Nrp1 is highly expressed by mesangial cells and that genetic deletion of the Nrp1 gene from PDGF receptor-β+ mesangial cells results in proteinuric disease and glomerulosclerosis, leading to renal failure and death within 6 wk of age in mice. The major defect is a failure of mesangial cell migration that is required to establish the mature glomerular tuft. In vitro data show that the potent chemotactic effect of PDGFB is lost in Nrp1-deficient mesangial cells. Biochemical analyses reveal that Nrp1 is required for PDGFB-dependent phosphorylation of p130 Crk-associated substrate (p130Cas), a large-scaffold molecule that is involved in motility of other cell types. In stark contrast, matrix adhesion and activation of ERK and Akt, which mediate proliferation of mesangial cells in response to PDGFB, are unaffected by the absence of Nrp1. Taken together, these results identify a critical cell-autonomous role for Nrp1 in the migratory behavior of mesangial cells and may help explain the renal effects that occur in patients receiving Nrp1-inhibitory drugs.
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Affiliation(s)
- Christina S Bartlett
- Division of Nephrology and Hypertension and Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Rizaldy P Scott
- Division of Nephrology and Hypertension and Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois.,Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada; and
| | - Isabel Anna Carota
- Division of Nephrology and Hypertension and Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Monika L Wnuk
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada; and
| | - Yashpal S Kanwar
- Division of Nephrology and Hypertension and Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Susan E Quaggin
- Division of Nephrology and Hypertension and Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois; .,Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada; and
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