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Bleathman F, Kausman JY, Hosking LM, Forbes TA. Ravulizumab facilitates reduced burden of vascular access, a major benefit in paediatric atypical haemolytic uraemic syndrome. J Paediatr Child Health 2024. [PMID: 38661088 DOI: 10.1111/jpc.16552] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/04/2024] [Accepted: 04/15/2024] [Indexed: 04/26/2024]
Abstract
BACKGROUND Atypical haemolytic uraemic syndrome (aHUS) is a rare thrombotic microangiopathy resulting from dysregulation of the alternative complement pathway, leading to multi-organ dysfunction and chronic kidney disease. Eculizumab is an anti-C5 monoclonal antibody therapy that has significantly improved aHUS disease control and patient outcomes, however it requires fortnightly intravenous dosing. This often necessitates long term central access and a high hospital attendance burden. Ravulizumab is a novel, next-generation anti-C5 monoclonal antibody engineered from eculizumab to reduce endosomal degradation of the antibody, increasing the dosing interval up to 8 weeks. CASE SERIES In this retrospective case series we present the transition of three children with aHUS from eculizumab to ravulizumab from a single tertiary paediatric nephrology service. All patients underwent genomic and immunological work up for aHUS, with no cause found. After stabilisation with eculizumab, two patients developed macrovascular thrombotic complications associated with indwelling central vascular catheters, ultimately leading to central access failure. All patients were transitioned from eculizumab to ravulizumab without relapse of aHUS. One patient successfully underwent deceased donor kidney transplantation with ravulizumab for complement inhibition. All patients have transitioned to peripheral access for infusions given the reduced frequency of dosing, maintaining good control of aHUS for 2-4 years. CONCLUSION Ravulizumab permits sufficiently reduced frequency of infusion to allow for administration by peripheral cannulation - removing the risks of long term central vascular access often required to deliver eculizumab to paediatric patients.
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Affiliation(s)
- Freya Bleathman
- Department of Nephrology, Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Joshua Y Kausman
- Department of Nephrology, Royal Children's Hospital, Melbourne, Victoria, Australia
- Kidney Flagship, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Laine M Hosking
- Immunology Laboratory, Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Thomas A Forbes
- Department of Nephrology, Royal Children's Hospital, Melbourne, Victoria, Australia
- Kidney Flagship, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
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Vanslambrouck JM, Neil JA, Rudraraju R, Mah S, Tan KS, Groenewegen E, Forbes TA, Karavendzas K, Elliott DA, Porrello ER, Subbarao K, Little MH. Kidney organoids reveal redundancy in viral entry pathways during ACE2-dependent SARS-CoV-2 infection. J Virol 2024; 98:e0180223. [PMID: 38334329 PMCID: PMC10949421 DOI: 10.1128/jvi.01802-23] [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: 11/20/2023] [Accepted: 12/21/2023] [Indexed: 02/10/2024] Open
Abstract
With a high incidence of acute kidney injury among hospitalized COVID-19 patients, considerable attention has been focussed on whether SARS-CoV-2 specifically targets kidney cells to directly impact renal function, or whether renal damage is primarily an indirect outcome. To date, several studies have utilized kidney organoids to understand the pathogenesis of COVID-19, revealing the ability for SARS-CoV-2 to predominantly infect cells of the proximal tubule (PT), with reduced infectivity following administration of soluble ACE2. However, the immaturity of standard human kidney organoids represents a significant hurdle, leaving the preferred SARS-CoV-2 processing pathway, existence of alternate viral receptors, and the effect of common hypertensive medications on the expression of ACE2 in the context of SARS-CoV-2 exposure incompletely understood. Utilizing a novel kidney organoid model with enhanced PT maturity, genetic- and drug-mediated inhibition of viral entry and processing factors confirmed the requirement for ACE2 for SARS-CoV-2 entry but showed that the virus can utilize dual viral spike protein processing pathways downstream of ACE2 receptor binding. These include TMPRSS- and CTSL/CTSB-mediated non-endosomal and endocytic pathways, with TMPRSS10 likely playing a more significant role in the non-endosomal pathway in renal cells than TMPRSS2. Finally, treatment with the antihypertensive ACE inhibitor, lisinopril, showed negligible impact on receptor expression or susceptibility of renal cells to infection. This study represents the first in-depth characterization of viral entry in stem cell-derived human kidney organoids with enhanced PTs, providing deeper insight into the renal implications of the ongoing COVID-19 pandemic. IMPORTANCE Utilizing a human iPSC-derived kidney organoid model with improved proximal tubule (PT) maturity, we identified the mechanism of SARS-CoV-2 entry in renal cells, confirming ACE2 as the sole receptor and revealing redundancy in downstream cell surface TMPRSS- and endocytic Cathepsin-mediated pathways. In addition, these data address the implications of SARS-CoV-2 exposure in the setting of the commonly prescribed ACE-inhibitor, lisinopril, confirming its negligible impact on infection of kidney cells. Taken together, these results provide valuable insight into the mechanism of viral infection in the human kidney.
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Affiliation(s)
- Jessica M. Vanslambrouck
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
| | - Jessica A. Neil
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia
| | - Rajeev Rudraraju
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia
| | - Sophia Mah
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
| | - Ker Sin Tan
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
| | - Ella Groenewegen
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
| | - Thomas A. Forbes
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
- Department of Nephrology, Royal Children’s Hospital, Melbourne, Australia
| | - Katerina Karavendzas
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
| | - David A. Elliott
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
- Australia Regenerative Medicine Institute, Monash University, Melbourne, Victoria, Australia
| | - Enzo R. Porrello
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
- Melbourne Centre for Cardiovascular Genomics and Regenerative Medicine, The Royal Children’s Hospital, Melbourne, Australia
- Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Melbourne, Australia
| | - Kanta Subbarao
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia
- The WHO Collaborating Centre for Reference and Research on Influenza, The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Melissa H. Little
- The Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
- Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Dorison A, Ghobrial I, Graham A, Peiris T, Forbes TA, See M, Das M, Saleem MA, Quinlan C, Lawlor KT, Ramialison M, Howden SE, Little MH. Kidney Organoids Generated Using an Allelic Series of NPHS2 Point Variants Reveal Distinct Intracellular Podocin Mistrafficking. J Am Soc Nephrol 2023; 34:88-109. [PMID: 36167728 PMCID: PMC10101587 DOI: 10.1681/asn.2022060707] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/31/2022] [Accepted: 09/06/2022] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND NPHS2 variants are the most common cause of steroid-resistant nephrotic syndrome in children >1 month old. Missense NPHS2 variants were reported to cause mistrafficking of the encoded protein, PODOCIN, but this conclusion was on the basis of overexpression in some nonpodocyte cell lines. METHODS We generated a series of human induced pluripotent stem cell (iPSC) lines bearing pathogenic missense variants of NPHS2 , encoding the protein changes p.G92C, p.P118L, p.R138Q, p.R168H, and p.R291W, and control lines. iPSC lines were also generated from a patient with steroid-resistant nephrotic syndrome (p.R168H homozygote) and a healthy heterozygous parent. All lines were differentiated into kidney organoids. Immunofluorescence assessed PODOCIN expression and subcellular localization. Podocytes were transcriptionally profiled and PODOCIN-NEPHRIN interaction interrogated. RESULTS All variant lines revealed reduced levels of PODOCIN protein in the absence of reduced transcription. Although wild-type PODOCIN localized to the membrane, distinct variant proteins displayed unique patterns of subcellular protein trafficking, some unreported. P118L and R138Q were preferentially retained in the endoplasmic reticulum (ER); R168H and R291W accumulated in the Golgi. Podocyte profiling demonstrated minimal disease-associated transcriptional change. All variants displayed podocyte-specific apoptosis, which was not linked to ER stress. NEPHRIN-PODOCIN colocalization elucidated the variant-specific effect on NEPHRIN association and hence NEPHRIN trafficking. CONCLUSIONS Specific variants of endogenous NPHS2 result in distinct subcellular PODOCIN localization within organoid podocytes. Understanding the effect of each variant on protein levels and localization and the effect on NEPHRIN provides additional insight into the pathobiology of NPHS2 variants. PODCAST This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2023_01_05_JASN2022060707.mp3.
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Affiliation(s)
- Aude Dorison
- Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Novo Nordisk Foundation Centre for Stem Cell Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Irene Ghobrial
- Murdoch Children’s Research Institute, Melbourne, Australia
| | - Alison Graham
- Murdoch Children’s Research Institute, Melbourne, Australia
| | | | - Thomas A. Forbes
- Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Royal Children’s Hospital, Melbourne, Australia
| | - Michael See
- Murdoch Children’s Research Institute, Melbourne, Australia
- Monash Bioinformatics Platform, Monash University, Clayton, Australia
| | - Mithun Das
- Murdoch Children’s Research Institute, Melbourne, Australia
| | - Moin A. Saleem
- Department of Paediatric Nephrology, Bristol Royal Hospital for Children, Bristol, United Kingdom
| | - Catherine Quinlan
- Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Royal Children’s Hospital, Melbourne, Australia
| | - Kynan T. Lawlor
- Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Novo Nordisk Foundation Centre for Stem Cell Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Mirana Ramialison
- Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Novo Nordisk Foundation Centre for Stem Cell Medicine, University of Copenhagen, Copenhagen, Denmark
- Australian Regenerative Medicine Institute, Clayton, Australia
| | - Sara E. Howden
- Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Novo Nordisk Foundation Centre for Stem Cell Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Melissa H. Little
- Murdoch Children’s Research Institute, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Novo Nordisk Foundation Centre for Stem Cell Medicine, University of Copenhagen, Copenhagen, Denmark
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Abstract
The ability to generate 3-dimensional models of the developing human kidney via the directed differentiation of pluripotent stem cells-termed kidney organoids-has been hailed as a major advance in experimental nephrology. Although these provide an opportunity to interrogate human development, model-specific kidney diseases facilitate drug screening and even deliver bioengineered tissue; most of these prophetic end points remain to be realized. Indeed, at present we are still finding out what we can learn and what we cannot learn from this approach. In this review, we will summarize the approaches available to generate models of the human kidney from stem cells, the existing successful applications of kidney organoids, their limitations, and remaining challenges.
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Affiliation(s)
- Aude Dorison
- Murdoch Children's Research Institute, Parkville, Melbourne, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Melbourne, Australia; Novo Nordisk Foundation Centre for Stem Cell Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Thomas A Forbes
- Murdoch Children's Research Institute, Parkville, Melbourne, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Melbourne, Australia; Department of Nephrology, Royal Children's Hospital, Parkville, Melbourne, Australia
| | - Melissa H Little
- Murdoch Children's Research Institute, Parkville, Melbourne, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Melbourne, Australia; Novo Nordisk Foundation Centre for Stem Cell Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
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Forbes TA, Wallace J, Kumble S, Delatycki MB, Stark Z. Neonatal Bartter syndrome diagnosed by rapid genomics following low risk pre-conception carrier screening. J Paediatr Child Health 2022; 58:758-761. [PMID: 35348259 PMCID: PMC9313891 DOI: 10.1111/jpc.15955] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 01/28/2022] [Accepted: 03/02/2022] [Indexed: 11/29/2022]
Abstract
Advances in the speed and accessibility of genomic sequencing are broadening the application of this technology to rapid, acute care diagnostics and pre-conception carrier screening. In both circumstances, genetic counselling plays a critical role in preparing couples for the strengths and limitations of the testing. For pre-conception carrier screening in particular, it is important that parents and clinicians are aware that even in the absence of an identified risk for recessive disease, a baby with a genetic condition may still be conceived. As an example, we present the genomic journey of a couple who underwent pre-conception carrier screening and following a low-risk result, delivered a baby boy who was diagnosed with Type 1 Bartter syndrome. Ultra-rapid, post-natal, trio whole genome sequencing resolved both parents as carriers of pathogenic variants in SLC12A1, a gene not included in the original pre-conception screening panel. This family's story highlights (i) the intricacy of gene selection for pre-conception screening panels, (ii) the benefits of high-quality pre-test genetic counselling in supporting families through adverse genomic findings and (iii) the role rapid genomics can play in resolving uncertainty for families and clinicians in circumstances where suspicion of genetic disease exists. This article is accompanied by a Patient Voice perspective written by the child's parents, placing emphasis on the essential role genetic counselling played in their journey.
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Affiliation(s)
- Thomas A Forbes
- Department of NephrologyRoyal Children's HospitalMelbourneVictoriaAustralia,Department of PaediatricsUniversity of MelbourneMelbourneVictoriaAustralia,Kidney Regeneration GroupMurdoch Children's Research InstituteMelbourneVictoriaAustralia
| | - Jane Wallace
- Victorian Clinical Genetics ServicesMurdoch Children's Research InstituteMelbourneVictoriaAustralia
| | - Smitha Kumble
- Victorian Clinical Genetics ServicesMurdoch Children's Research InstituteMelbourneVictoriaAustralia
| | - Martin B Delatycki
- Department of PaediatricsUniversity of MelbourneMelbourneVictoriaAustralia,Victorian Clinical Genetics ServicesMurdoch Children's Research InstituteMelbourneVictoriaAustralia
| | - Zornitza Stark
- Department of PaediatricsUniversity of MelbourneMelbourneVictoriaAustralia,Victorian Clinical Genetics ServicesMurdoch Children's Research InstituteMelbourneVictoriaAustralia,Australian Genomics Health AllianceMelbourneVictoriaAustralia
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6
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Forbes TA, Brown BD, Lai C. Therapeutic RNA interference: A novel approach to the treatment of primary hyperoxaluria. Br J Clin Pharmacol 2021; 88:2525-2538. [PMID: 34022071 PMCID: PMC9291495 DOI: 10.1111/bcp.14925] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [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: 11/26/2020] [Revised: 04/19/2021] [Accepted: 05/08/2021] [Indexed: 12/13/2022] Open
Abstract
RNA interference (RNAi) is a natural biological pathway that inhibits gene expression by targeted degradation or translational inhibition of cytoplasmic mRNA by the RNA induced silencing complex. RNAi has long been exploited in laboratory research to study the biological consequences of the reduced expression of a gene of interest. More recently RNAi has been demonstrated as a therapeutic avenue for rare metabolic diseases. This review presents an overview of the cellular RNAi machinery as well as therapeutic RNAi design and delivery. As a clinical example we present primary hyperoxaluria, an ultrarare inherited disease of increased hepatic oxalate production which leads to recurrent calcium oxalate kidney stones. In the most common form of the disease (Type 1), end‐stage kidney disease occurs in childhood or young adulthood, often necessitating combined kidney and liver transplantation. In this context we discuss nedosiran (Dicerna Pharmaceuticals, Inc.) and lumasiran (Alnylam Pharmaceuticals), which are both novel RNAi therapies for primary hyperoxaluria that selectively reduce hepatic expression of lactate dehydrogenase and glycolate oxidase respectively, reducing hepatic oxalate production and urinary oxalate levels. Finally, we consider future optimizations advances in RNAi therapies.
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Affiliation(s)
- Thomas A Forbes
- Royal Children's Hospital, Parkville, Victoria, Australia.,Murdoch Children's Research Institute, Parkville, Victoria, Australia.,University of Melbourne, Parkville, Victoria, Australia
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7
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Goldstein EZ, Pertsovskaya V, Forbes TA, Dupree JL, Gallo V. Prolonged Environmental Enrichment Promotes Developmental Myelination. Front Cell Dev Biol 2021; 9:665409. [PMID: 33981706 PMCID: PMC8107367 DOI: 10.3389/fcell.2021.665409] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [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: 02/08/2021] [Accepted: 04/07/2021] [Indexed: 01/19/2023] Open
Abstract
Postnatal neurodevelopment is profoundly influenced by environmental experiences. Environmental enrichment is a commonly used experimental paradigm that has uncovered numerous examples of experience-dependent plasticity in health and disease. However, the role of environmental enrichment in normal development, especially glial development, is largely unexplored. Oligodendrocytes, the myelin-forming glia in the central nervous system, provide metabolic support to axons and establish efficient saltatory conduction by producing myelin. Indeed, alterations in myelin are strongly correlated with sensory, cognitive, and motor function. The timing of developmental myelination is uniquely positioned to be influenced by environmental stimuli, as peak myelination occurs postnatally and continues into adulthood. To determine if developmental myelination is impacted by environmental experience, mice were housed in an enriched environment during peak myelination through early adulthood. Using translating ribosome affinity purification, oligodendrocyte-specific RNAs were isolated from subcortical white matter at various postnatal ages. RNA-sequencing revealed that differences in the oligodendrocyte translatome were predominantly evident after prolonged and continuous environmental enrichment. These translational changes corresponded with altered oligodendrocyte lineage cell dynamics and enhanced myelination. Furthermore, consistent with increased developmental myelination, enriched mice displayed enhanced motor coordination on a beam walking task. These findings indicate that protracted environmental stimulation is sufficient to modulate developmental myelination and to promote behavioral function.
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Affiliation(s)
- Evan Z Goldstein
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, United States
| | - Vera Pertsovskaya
- School of Medicine and Health Sciences, The George Washington University, Washington, DC, United States
| | - Thomas A Forbes
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, United States
| | - Jeffrey L Dupree
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, United States
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8
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Howden SE, Wilson SB, Groenewegen E, Starks L, Forbes TA, Tan KS, Vanslambrouck JM, Holloway EM, Chen YH, Jain S, Spence JR, Little MH. Plasticity of distal nephron epithelia from human kidney organoids enables the induction of ureteric tip and stalk. Cell Stem Cell 2021; 28:671-684.e6. [PMID: 33378647 PMCID: PMC8026527 DOI: 10.1016/j.stem.2020.12.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [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: 03/14/2020] [Revised: 10/05/2020] [Accepted: 11/30/2020] [Indexed: 02/06/2023]
Abstract
During development, distinct progenitors contribute to the nephrons versus the ureteric epithelium of the kidney. Indeed, previous human pluripotent stem-cell-derived models of kidney tissue either contain nephrons or pattern specifically to the ureteric epithelium. By re-analyzing the transcriptional distinction between distal nephron and ureteric epithelium in human fetal kidney, we show here that, while existing nephron-containing kidney organoids contain distal nephron epithelium and no ureteric epithelium, this distal nephron segment alone displays significant in vitro plasticity and can adopt a ureteric epithelial tip identity when isolated and cultured in defined conditions. "Induced" ureteric epithelium cultures can be cryopreserved, serially passaged without loss of identity, and transitioned toward a collecting duct fate. Cultures harboring loss-of-function mutations in PKHD1 also recapitulate the cystic phenotype associated with autosomal recessive polycystic kidney disease.
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Affiliation(s)
- Sara E Howden
- Murdoch Children's Research Institute, Parkville, Melbourne, 3052 VIC, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, 3052 VIC, Australia.
| | - Sean B Wilson
- Murdoch Children's Research Institute, Parkville, Melbourne, 3052 VIC, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, 3052 VIC, Australia
| | - Ella Groenewegen
- Murdoch Children's Research Institute, Parkville, Melbourne, 3052 VIC, Australia
| | - Lakshi Starks
- Murdoch Children's Research Institute, Parkville, Melbourne, 3052 VIC, Australia
| | - Thomas A Forbes
- Murdoch Children's Research Institute, Parkville, Melbourne, 3052 VIC, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, 3052 VIC, Australia; Department of Nephrology, Royal Children's Hospital, Flemington Rd, Parkville, Melbourne, 3052 VIC, Australia
| | - Ker Sin Tan
- Murdoch Children's Research Institute, Parkville, Melbourne, 3052 VIC, Australia
| | | | | | | | | | - Jason R Spence
- University of Michigan Medical School, Ann Arbor, MI, USA
| | - Melissa H Little
- Murdoch Children's Research Institute, Parkville, Melbourne, 3052 VIC, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, 3052 VIC, Australia; Department of Anatomy and Neuroscience, The University of Melbourne, Melbourne, VIC, Australia.
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9
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Majmundar AJ, Buerger F, Forbes TA, Klämbt V, Schneider R, Deutsch K, Kitzler TM, Howden SE, Scurr M, Tan KS, Krzeminski M, Widmeier E, Braun DA, Lai E, Ullah I, Amar A, Kolb A, Eddy K, Chen CH, Salmanullah D, Dai R, Nakayama M, Ottlewski I, Kolvenbach CM, Onuchic-Whitford AC, Mao Y, Mann N, Nabhan MM, Rosen S, Forman-Kay JD, Soliman NA, Heilos A, Kain R, Aufricht C, Mane S, Lifton RP, Shril S, Little MH, Hildebrandt F. Recessive NOS1AP variants impair actin remodeling and cause glomerulopathy in humans and mice. Sci Adv 2021; 7:eabe1386. [PMID: 33523862 PMCID: PMC10763988 DOI: 10.1126/sciadv.abe1386] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 11/11/2020] [Indexed: 06/12/2023]
Abstract
Nephrotic syndrome (NS) is a leading cause of chronic kidney disease. We found recessive NOS1AP variants in two families with early-onset NS by exome sequencing. Overexpression of wild-type (WT) NOS1AP, but not cDNA constructs bearing patient variants, increased active CDC42 and promoted filopodia and podosome formation. Pharmacologic inhibition of CDC42 or its effectors, formin proteins, reduced NOS1AP-induced filopodia formation. NOS1AP knockdown reduced podocyte migration rate (PMR), which was rescued by overexpression of WT Nos1ap but not by constructs bearing patient variants. PMR in NOS1AP knockdown podocytes was also rescued by constitutively active CDC42Q61L or the formin DIAPH3 Modeling a NOS1AP patient variant in knock-in human kidney organoids revealed malformed glomeruli with increased apoptosis. Nos1apEx3-/Ex3- mice recapitulated the human phenotype, exhibiting proteinuria, foot process effacement, and glomerulosclerosis. These findings demonstrate that recessive NOS1AP variants impair CDC42/DIAPH-dependent actin remodeling, cause aberrant organoid glomerulogenesis, and lead to a glomerulopathy in humans and mice.
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Affiliation(s)
- Amar J Majmundar
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Florian Buerger
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Thomas A Forbes
- Kidney Development, Disease and Regeneration Group, Murdoch Children's Research Institute, Parkville, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
- Department of Nephrology, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Verena Klämbt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ronen Schneider
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Konstantin Deutsch
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Thomas M Kitzler
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Sara E Howden
- Kidney Development, Disease and Regeneration Group, Murdoch Children's Research Institute, Parkville, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
| | - Michelle Scurr
- Kidney Development, Disease and Regeneration Group, Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Ker Sin Tan
- Kidney Development, Disease and Regeneration Group, Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Mickaël Krzeminski
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Eugen Widmeier
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Daniela A Braun
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ethan Lai
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ihsan Ullah
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ali Amar
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Amy Kolb
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kaitlyn Eddy
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Chin Heng Chen
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Daanya Salmanullah
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Rufeng Dai
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Makiko Nakayama
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Isabel Ottlewski
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Caroline M Kolvenbach
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ana C Onuchic-Whitford
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Youying Mao
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Nina Mann
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Marwa M Nabhan
- Department of Pediatrics, Center for Pediatric Nephrology and Transplantation, Kasr Al Ainy Medical School, Cairo University, Cairo, Egypt
| | - Seymour Rosen
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Julie D Forman-Kay
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Neveen A Soliman
- Department of Pediatrics, Center for Pediatric Nephrology and Transplantation, Kasr Al Ainy Medical School, Cairo University, Cairo, Egypt
| | - Andreas Heilos
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | - Renate Kain
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | | | - Shrikant Mane
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Richard P Lifton
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- Laboratory of Human Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Shirlee Shril
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Melissa H Little
- Kidney Development, Disease and Regeneration Group, Murdoch Children's Research Institute, Parkville, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
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10
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Forbes TA, Goldstein EZ, Dupree JL, Jablonska B, Scafidi J, Adams KL, Imamura Y, Hashimoto-Torii K, Gallo V. Environmental enrichment ameliorates perinatal brain injury and promotes functional white matter recovery. Nat Commun 2020; 11:964. [PMID: 32075970 PMCID: PMC7031237 DOI: 10.1038/s41467-020-14762-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [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: 04/17/2018] [Accepted: 01/31/2020] [Indexed: 12/14/2022] Open
Abstract
Hypoxic damage to the developing brain due to preterm birth causes many anatomical changes, including damage to the periventricular white matter. This results in the loss of glial cells, significant disruptions in myelination, and thereby cognitive and behavioral disabilities seen throughout life. Encouragingly, these neurological morbidities can be improved by environmental factors; however, the underlying cellular mechanisms remain unknown. We found that early and continuous environmental enrichment selectively enhances endogenous repair of the developing white matter by promoting oligodendroglial maturation, myelination, and functional recovery after perinatal brain injury. These effects require increased exposure to socialization, physical activity, and cognitive enhancement of surroundings-a complete enriched environment. Using RNA-sequencing, we identified oligodendroglial-specific responses to hypoxic brain injury, and uncovered molecular mechanisms involved in enrichment-induced recovery. Together, these results indicate that myelin plasticity induced by modulation of the neonatal environment can be targeted as a therapeutic strategy for preterm birth.
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Affiliation(s)
- Thomas A Forbes
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University, Washington, DC, 20052, USA
| | - Evan Z Goldstein
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, 20010, USA
| | - Jeffrey L Dupree
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, 23284, USA
| | - Beata Jablonska
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University, Washington, DC, 20052, USA
| | - Joseph Scafidi
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University, Washington, DC, 20052, USA
| | - Katrina L Adams
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, 20010, USA
| | - Yuka Imamura
- Institute for Personalized Medicine, Penn State University, College of Medicine, Hershey, PA, 17033, USA
| | - Kazue Hashimoto-Torii
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, 20010, USA
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC, 20010, USA. .,Institute for Biomedical Sciences, The George Washington University, Washington, DC, 20052, USA.
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11
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Forbes TA, Howden SE, Lawlor K, Phipson B, Maksimovic J, Hale L, Wilson S, Quinlan C, Ho G, Holman K, Bennetts B, Crawford J, Trnka P, Oshlack A, Patel C, Mallett A, Simons C, Little MH. Patient-iPSC-Derived Kidney Organoids Show Functional Validation of a Ciliopathic Renal Phenotype and Reveal Underlying Pathogenetic Mechanisms. Am J Hum Genet 2018; 102:816-831. [PMID: 29706353 DOI: 10.1016/j.ajhg.2018.03.014] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/05/2018] [Indexed: 02/07/2023] Open
Abstract
Despite the increasing diagnostic rate of genomic sequencing, the genetic basis of more than 50% of heritable kidney disease remains unresolved. Kidney organoids differentiated from induced pluripotent stem cells (iPSCs) of individuals affected by inherited renal disease represent a potential, but unvalidated, platform for the functional validation of novel gene variants and investigation of underlying pathogenetic mechanisms. In this study, trio whole-exome sequencing of a prospectively identified nephronophthisis (NPHP) proband and her parents identified compound-heterozygous variants in IFT140, a gene previously associated with NPHP-related ciliopathies. IFT140 plays a key role in retrograde intraflagellar transport, but the precise downstream cellular mechanisms responsible for disease presentation remain unknown. A one-step reprogramming and gene-editing protocol was used to derive both uncorrected proband iPSCs and isogenic gene-corrected iPSCs, which were differentiated to kidney organoids. Proband organoid tubules demonstrated shortened, club-shaped primary cilia, whereas gene correction rescued this phenotype. Differential expression analysis of epithelial cells isolated from organoids suggested downregulation of genes associated with apicobasal polarity, cell-cell junctions, and dynein motor assembly in proband epithelial cells. Matrigel cyst cultures confirmed a polarization defect in proband versus gene-corrected renal epithelium. As such, this study represents a "proof of concept" for using proband-derived iPSCs to model renal disease and illustrates dysfunctional cellular pathways beyond the primary cilium in the setting of IFT140 mutations, which are established for other NPHP genotypes.
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12
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Abstract
International guidelines in peritoneal dialysis (PD) advocate for regular application of topical mupirocin in chronic PD exit-site care. A strong evidence base links this treatment to reduced rates of exit-site infections and peritonitis. However, emerging reports of increasing mupirocin resistance and gram-negative infections are threatening the long-term viability of topical antibiotic ointments as a prophylactic treatment. Medical grade honey has multiple proven antibacterial and wound healing properties. High-quality randomized controlled trial evidence (the HONEYPOT trial), however, does not support the use of topical medical-grade honey over antibiotic ointments for the prevention of exit-site infection and peritonitis in adults. Pediatric representation in these studies is low, and these findings may not extrapolate to the pediatric context, which has a higher incidence of PD-related infection and a lower prevalence of diabetes.We present a series of 8 pediatric patients treated with topical Medihoney (Comvita, Paengaroa, New Zealand) in the context of poor exit-site condition, persistent infection, and recurrent granuloma where the addition of honey was felt to produce remarkable improvement in exit-site status.Medihoney is the first-line prophylactic exit-site ointment in PD exit sites at our institution and has been implicated in the salvage of peritoneal access in some patients. No exclusively pediatric studies have been performed; however, existing literature suggests a beneficial effect in promoting healing of infected wounds with a lower risk of developing antimicrobial resistance.
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Affiliation(s)
- Thomas A Forbes
- Department of Nephrology, The Royal Children's Hospital, Parkville, Victoria, Australia
| | - Loren Shaw
- Department of Nephrology, The Royal Children's Hospital, Parkville, Victoria, Australia
| | - Catherine Quinlan
- Department of Nephrology, The Royal Children's Hospital, Parkville, Victoria, Australia
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13
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Abstract
To date, studies have demonstrated the dynamic influence of exogenous environmental stimuli on multiple regions of the brain. This environmental influence positively and negatively impacts programs governing myelination, and acts on myelinating oligodendrocyte (OL) cells across the human lifespan. Developmentally, environmental manipulation of OL progenitor cells (OPCs) has profound effects on the establishment of functional cognitive, sensory, and motor programs. Furthermore, central nervous system (CNS) myelin remains an adaptive entity in adulthood, sensitive to environmentally induced structural changes. Here, we discuss the role of environmental stimuli on mechanisms governing programs of CNS myelination under normal and pathological conditions. Importantly, we highlight how these extrinsic cues can influence the intrinsic power of myelin plasticity to promote functional recovery.
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Affiliation(s)
- Thomas A Forbes
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, DC 20010, USA; The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA.
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, DC 20010, USA; The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA.
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14
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Forbes TA, McMinn A, Crawford N, Leask J, Danchin M. Vaccination uptake by vaccine-hesitant parents attending a specialist immunization clinic in Australia. Hum Vaccin Immunother 2015; 11:2895-903. [PMID: 26366978 DOI: 10.1080/21645515.2015.1070997] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Vaccine hesitancy (VH) is an issue of global concern. The quality of communication between healthcare providers and parents can influence parental immunization acceptance. We aimed to describe immunization uptake following specialist immunization clinic (SIC) consultation for Australian children of VH parents as a cohort, and according to pre-clinic parental position on immunization. At a single tertiary pediatric SIC (RCH, Melbourne) a retrospective descriptive study classified VH families according to 3 proposed parental positions on immunization at initial clinic attendance. Immunization status at follow up was ascertained via the Australian Children's Immunization Register and National HPV Program Register and compared between groups. Of the VH cohort, 13/38 (34%) families were classified as hesitant, 21 (55%) as late/selective vaccinators and 4 (11%) as vaccine refusers. Mean follow up post-SIC attendance was 14.5 months. For the overall VH cohort, the majority chose selective immunization (42%) following SIC consultation. When analyzed by pre-clinic parental position on immunization, there was a trend for hesitant families to proceed with full immunization, selective families to continue selective immunization and refusing families to remain unimmunised (p < 0.0001). The most commonly omitted vaccines were hepatitis B (66%) and Haemophilus influenzae type B (55%), followed by the meningococcal C conjugate vaccine (53%) and measles, mumps and rubella vaccine (53%). Immunization outcome appears to correlate with pre-clinic parental position on immunization for the majority of families attending a SIC in Australia, with selective immunization the most common outcome. Tailored communication approaches based on parental position on immunization may optimise clinic resources and engagement of families, but require prospective research evaluation.
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Affiliation(s)
- Thomas A Forbes
- a Department of Nephrology ; Royal Children's Hospital ; Parkville , Victoria , Australia
| | - Alissa McMinn
- b SAEFVIC and Vaccine and Immunisation Research Group; Murdoch Children's Research Institute ; Parkville , VIC Australia
| | - Nigel Crawford
- b SAEFVIC and Vaccine and Immunisation Research Group; Murdoch Children's Research Institute ; Parkville , VIC Australia.,c Department of General Medicine ; Royal Children's Hospital ; Parkville , Victoria , Australia.,d Murdoch Childrens Research Institute; Parkville, Victoria, Australia ; Department of Pediatrics and School of Population and Global Health; University of Melbourne ; Parkville , VIC Australia
| | - Julie Leask
- e School of Public health; University of Sydney ; New South Wales , Australia
| | - Margie Danchin
- b SAEFVIC and Vaccine and Immunisation Research Group; Murdoch Children's Research Institute ; Parkville , VIC Australia.,c Department of General Medicine ; Royal Children's Hospital ; Parkville , Victoria , Australia.,d Murdoch Childrens Research Institute; Parkville, Victoria, Australia ; Department of Pediatrics and School of Population and Global Health; University of Melbourne ; Parkville , VIC Australia
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15
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Forbes TA, Watson AR, Zurowska A, Shroff R, Bakkaloglu S, Vondrak K, Fischbach M, Van de Walle J, Ariceta G, Edefonti A, Aufricht C, Jankauskiene A, Holta T, Ekim M, Schmitt CP, Stefanidis C. Adherence to transition guidelines in European paediatric nephrology units. Pediatr Nephrol 2014; 29:1617-24. [PMID: 24710747 DOI: 10.1007/s00467-014-2809-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 01/31/2014] [Accepted: 03/11/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND There is increasing focus on the problems involved in the transition and transfer of young adult patients from paediatric to adult renal units. This situation was addressed by the 2011 International Pediatric Nephrology Association/International Society of Nephrology (IPNA/ISN) Consensus Statement on transition. METHODS We performed a survey of transition practices of 15 paediatric nephrology units across Europe 2 years after publication of the consensus statement. RESULTS Two thirds of units were aware of the guidelines, and one third had integrated them into their transition practice. Forty-seven per cent of units transfer five or fewer patients with chronic kidney disease (CKD) stage 5 per year to a median of five adult centres, with higher numbers of CKD stages 2-4 patients. Seventy-three per cent of units were required by the hospital or government to transfer patients by a certain age. Eighty per cent of units commenced transition planning after the patient turned 15 years of age and usually within 1-2 years of the compulsory transfer age. Forty-seven per cent of units used a transition or transfer clinic. Prominent barriers to effective transition were patient and parent attachment to the paediatric unit and difficulty in allowing the young person to perform self-care. CONCLUSIONS Whereas awareness of the consensus statement is suboptimal, it has had some impact on practice. Adult nephrologists receive transferred patients infrequently, and the process of transition is introduced too late by paediatricians. Government- and hospital-driven age-based transfer policies distract focus from the achievement of competencies in self care. Variable use of transition clinics, written patient information and support groups is probably due to economic and human-resource limitations. The consensus statement provides a standard for evolving and evaluating transition policies jointly agreed upon by paediatric and adult units.
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Affiliation(s)
- Thomas A Forbes
- Nottingham Children's Hospital, Children's Renal and Urology Unit, QMC Campus, Derby Road, Nottingham, NG7 2UH, UK
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16
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Forbes TA, Bradbury MG, Goodship THJ, McKiernan PJ, Milford DV. Changing strategies for organ transplantation in atypical haemolytic uraemic syndrome: a tertiary case series. Pediatr Transplant 2013; 17:E93-9. [PMID: 23461281 DOI: 10.1111/petr.12066] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/24/2013] [Indexed: 11/26/2022]
Abstract
We present three cases of organ transplantation for atypical haemolytic uraemic syndrome secondary to complement factor H mutation: one isolated renal transplant; one previously reported isolated liver transplant; and one combined liver and kidney transplant. All three patients were treated prior to the licensing of eculizumab for this condition, and all have had favourable outcomes with maintenance of graft function for years following transplantation. We discuss the evolution of transplantation therapy for aHUS over the last two decades. Transplantation decision-making in aHUS has evolved over this time with expanding knowledge of pathophysiology and genetics, alongside refined plasma exchange and anticoagulation protocols and improved centre experience. Our cases demonstrate how individual patient factors within this heterogeneous condition also underlie transplantation decisions and outcomes. Whilst our cases demonstrate that transplantation in aHUS can be a successful long-term treatment providing good quality of life, worldwide experience has proven that most curative treatment for aHUS strategies represents significant risks. Whether new pharmacotherapies such as eculizumab will alter this risk is yet to be determined.
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Affiliation(s)
- Thomas A Forbes
- Department of Nephrology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK
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17
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Forbes TA, Hopkins L, Schneider B, Lazarus L, Leitenberg D, Constant S, Schwartz A, Patierno S, Ceryak S. Abstract 5456: Potential role of nitric oxide in chromium-induced lung carcinogenesis. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-5456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Certain hexavalent chromium [Cr(VI)] compounds are well established human respiratory toxins and carcinogens of occupational and environmental relevance. Our recent studies have shown that intranasal (IN) exposure of Balb/c mice to particulate zinc Cr(VI) compounds leads to pronounced innate inflammation in the lung, which we postulate plays a significant role in pulmonary tumorigenesis. Nitric oxide (NO) has been shown to be induced via inflammatory response mediators, and has been implicated in the progression of different cancers, including lung. Moreover, NO-induced tumor invasiveness has been correlated with enhanced matrix metalloproteinase (MMP) expression in lung tumor cell lines. Of particular relevance to the present study is the finding that in vitro exposure of human lung cells to Cr(VI) in culture led to increased NO production. The aim of the present study was to explore the role of NO in chromium-induced lung tumorigenesis. BALB/c mice received weekly IN delivery of either saline or 10 ug particulate basic zinc chromate, which is an intermediately water soluble chromate typically encountered in mining/chromate production facilities and which is also present as an environmental atmospheric contaminant in urban areas surrounding ferrochrome production facilities. After 9 weeks, immune cells, cytokines, NO, MMPs and pathologic features of lung injury and inflammation were measured in airway lavage fluid and lung tissue, at both 24h after the final Cr(VI) dose, as well as 1 week later. As previously shown, repetitive Cr(VI) exposure induced a neutrophilic inflammatory airway response 24h after treatment. Neutrophils were subsequently replaced by increasing numbers of macrophages 1 week after treatment. Peribronchiolar inflammation was observed in chromate-exposed mice, and was accompanied by a 100-fold increase in pro-MMP9 release into the airways. Notably, airway NO was significantly increased ∼ 1.9 fold in Cr(VI)-exposed mice as compared to their saline-treated counterparts at both time points following final exposure. Moreover, immunoreactivity of induced nitric oxide synthase (iNOS) was markedly increased in airways exposed to Cr(VI), with staining localized to infiltrating immune cells. In conclusion, repetitive exposure to particulate chromate induces an inflammatory environment in the lung, accompanied by enhanced NO production, which we postulate may promote Cr(VI) carcinogenesis. Supported by NIH grants CA107972 and ES017334 to SC and ES017307 to SRP.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5456. doi:1538-7445.AM2012-5456
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Affiliation(s)
| | | | | | | | | | | | | | | | - Susan Ceryak
- 1The George Washington University, Washington, DC
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18
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Abstract
Five different combinations of digital shaping parameters were tested for a newly assembled. 109Cd source, K X-ray fluorescence bone lead system. System calibration results are presented, along with analyses of measurement uncertainty and reproducibility obtained from repeat measurements of a bone phantom and a human tibia. Digital shaping parameters of 2.4 micros for a rise time/fall time and 1.2 micros for a flat top width were identified as superior. The digital system provided significant improvements in overall measurement precision, with gains of at least 25-35% over conventional system results.
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Affiliation(s)
- D E Fleming
- Department of Biomedical Technologies, University of Vermont, Burlington 05405-0068, USA.
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