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Dong F, Amlal H, Venkatakrishnan J, Zhang J, Fry M, Yuan Y, Cheng YC, Hu YC, Kao WWY. The gene therapy for corneal pathology with novel nonsense cystinosis mouse lines created by CRISPR Gene Editing. Ocul Surf 2023; 29:432-443. [PMID: 37355021 PMCID: PMC10725217 DOI: 10.1016/j.jtos.2023.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/26/2023] [Accepted: 06/02/2023] [Indexed: 06/26/2023]
Abstract
PURPOSE Cystinosis is an autosomal recessive lysosomal storage disease (LSDs) caused by mutations in the gene encoding cystinosin (CTNS) that leads to cystine crystal accumulation in the lysosome that compromises cellular functions resulting in tissue damage and organ failure, especially in kidneys and eyes. However, the underlying molecular mechanism of its pathogenesis remains elusive. Two novel mice lines created via CRISPR are used to examine the pathogenesis of cystinosis in the kidney and cornea and the treatment efficacy of corneal pathology using self-complimentary Adeno-associated viral (scAAV-CTNS) vector. METHODS The CRISPR technique generated two novel cystinotic mouse lines, Ctnsis1 (an insertional mutation) and Ctnsis2 (a nonsense mutation). Immune histochemistry, renal functions test and HRT2 in vivo confocal microscopy were used to evaluate the age-related renal pathogenesis and treatment efficacy of the scAAV-CTNS virus in corneal pathology. RESULTS Both mutations lead to the production of truncated Ctns proteins. Ctnsis1 and Ctnsis 2 mice exhibit the characteristic of cystinotic corneal crystal phenotype at four-week-old. Treatment with the scAAV-CTNS viral vector decreased the corneal crystals in the treated mice cornea. Ctnsis 1 show renal abnormalities manifested by increased urine volume, reduced urine osmolality, and the loss of response to Desmopressin (dDAVP) at 22-month-old but Ctnsis2 don't manifest renal pathology up to 2 years of age. CONCLUSIONS Both Ctnsis1 and Ctnsis2 mice exhibit phenotypes resembling human intermediate nephropathic and ocular cystinosis, respectively. scAAV-CTNS viral vectors reduce the corneal cystine crystals and have a great potential as a therapeutic strategy for treating patients suffering from cystinosis.
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Affiliation(s)
- Fei Dong
- Department of Ophthalmology, University of Cincinnati, Cincinnati, OH, USA
| | - Hassane Amlal
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, USA
| | | | - Jianhua Zhang
- Department of Ophthalmology, University of Cincinnati, Cincinnati, OH, USA
| | - Matthew Fry
- Department of Ophthalmology, University of Cincinnati, Cincinnati, OH, USA
| | - Yong Yuan
- Department of Ophthalmology, University of Cincinnati, Cincinnati, OH, USA
| | - Yu Chia Cheng
- Department of Ophthalmology, University of Cincinnati, Cincinnati, OH, USA
| | - Yueh-Chiang Hu
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Winston W-Y Kao
- Department of Ophthalmology, University of Cincinnati, Cincinnati, OH, USA.
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El Younsi M, Trabelsi M, Ben Youssef S, Ouertani I, Hammi Y, Achour A, Maazoul F, Kharrat M, Gargah T, M'rad R. Clinical and genetic characteristics of Tunisian children with infantile nephropathic cystinosis. Pediatr Nephrol 2023; 38:119-129. [PMID: 35445972 DOI: 10.1007/s00467-022-05525-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 02/25/2022] [Accepted: 02/25/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND Nephropathic cystinosis is an autosomal recessive disease caused by a mutation in the CTNS gene which encodes cystinosin, a lysosomal cystine transporter. The spectrum of mutations in the CTNS gene is not well defined in the North African population. Here, we investigated twelve patients with nephropathic cystinosis belonging to eight Tunisian families in order to analyze the clinical and genetic characteristics of Tunisian children with infantile nephropathic cystinosis. METHODS Clinical data were collected retrospectively. Molecular analysis of the CTNS gene was performed by Sanger sequencing. RESULTS We describe a new splicing mutation c.971-1G > C in the homozygous state in 6/12 patients which seems to be a founder mutation. The reported deletion of 23nt c.771_793 Del (p.Gly258Serfs*30) was detected in a homozygous state in one patient and in a heterozygous compound state with the c.971-1G > C mutation in 3/12 patients. Two of 12 patients have a deletion of exons 4 and 5 of the CTNS gene. None of our patients had the most common 57-kb deletion. CONCLUSIONS The mutational spectrum in the Tunisian population is different from previously described populations. Thus, a molecular diagnostic strategy must be implemented in Tunisia, by targeting as a priority the common mutations described in this country. Such a strategy will allow a cost-effective diagnosis confirmation as well as early administration of treatment with oral cysteamine. A higher resolution version of the Graphical abstract is available as Supplementary information.
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Affiliation(s)
- Mariem El Younsi
- Laboratoire de Génétique Humaine, LR99ES10, Faculté de Médecine de Tunis, Université de Tunis El Manar, 1007, Tunis, Tunisia
| | - Médiha Trabelsi
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Sandra Ben Youssef
- Service de Pédiatrie Néphrologique Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Inès Ouertani
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Yousra Hammi
- Service de Pédiatrie Néphrologique Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Ahlem Achour
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Faouzi Maazoul
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Maher Kharrat
- Laboratoire de Génétique Humaine, LR99ES10, Faculté de Médecine de Tunis, Université de Tunis El Manar, 1007, Tunis, Tunisia
| | - Tahar Gargah
- Service de Pédiatrie Néphrologique Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Ridha M'rad
- Laboratoire de Génétique Humaine, LR99ES10, Faculté de Médecine de Tunis, Université de Tunis El Manar, 1007, Tunis, Tunisia. .,Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia.
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Jamalpoor A, Othman A, Levtchenko EN, Masereeuw R, Janssen MJ. Molecular Mechanisms and Treatment Options of Nephropathic Cystinosis. Trends Mol Med 2021; 27:673-686. [PMID: 33975805 DOI: 10.1016/j.molmed.2021.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 11/15/2022]
Abstract
Nephropathic cystinosis is a severe, monogenic systemic disorder that presents early in life and leads to progressive organ damage, particularly affecting the kidneys. It is caused by mutations in the CTNS gene, which encodes the lysosomal transporter cystinosin, resulting in intralysosomal accumulation of cystine. Recent studies demonstrated that the loss of cystinosin is associated with disrupted autophagy dynamics, accumulation of distorted mitochondria, and increased oxidative stress, leading to abnormal proliferation and dysfunction of kidney cells. We discuss these molecular mechanisms driving nephropathic cystinosis. Further, we consider how unravelling molecular mechanisms supports the identification and development of new strategies for cystinosis by the use of small molecules, biologicals, and genetic rescue of the disease in vitro and in vivo.
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Affiliation(s)
- Amer Jamalpoor
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584, CG, Utrecht, The Netherlands
| | - Amr Othman
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584, CG, Utrecht, The Netherlands
| | - Elena N Levtchenko
- Department of Pediatric Nephrology & Growth and Regeneration, University Hospitals Leuven & KU Leuven, Leuven, Belgium
| | - Rosalinde Masereeuw
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584, CG, Utrecht, The Netherlands.
| | - Manoe J Janssen
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584, CG, Utrecht, The Netherlands.
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Batista LFS, Torrecilha RBP, Silva RB, Utsunomiya YT, Silva TBF, Tomokane TY, Pacheco AD, Bosco AM, Paulan SC, Rossi CN, Costa GNO, Marcondes M, Ciarlini PC, Nunes CM, Matta VLR, Laurenti MD. Chromosomal segments may explain the antibody response cooperation for canine leishmaniasis pathogenesis. Vet Parasitol 2020; 288:109276. [PMID: 33152678 DOI: 10.1016/j.vetpar.2020.109276] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 12/22/2022]
Abstract
Visceral leishmaniasis (VL) is marked by hyperactivation of a humoral response secreting high quantity of immunoglobulins (Igs) that are inaccessible to intracellular parasites. Here we investigated the contributions of the antibody response to the canine leishmaniasis pathogenesis. Using correlation and genome-wide association analysis, we investigated the relationship of anti-Leishmania infantum immunoglobulin classes levels with parasite burden, clinical response, renal/hepatic biochemical, and oxidative stress markers in dogs from endemic areas of VL. Immunoglobulin G (IgG) and IgA were positively correlated with parasite burden on lymph node and blood. Increased IgG, IgA and IgE levels were associated with severe canine leishmaniasis (CanL) whereas IgM was elevated in uninfected exposed dogs. Correlations of IgM, IgG and IgA with creatinine, urea, AST and ALT levels in the serum were suggested an involvement of those Igs with renal and hepatic changes. The correlogram of oxidative radicals and antioxidants revealed a likely relationship of IgM, IgG and IgA with oxidative stress and lipid peroxidation in the blood, suggested as mechanisms mediating tissue damage and CanL worsening. The gene mapping on chromosomal segments associated with the quantitative variation of immunoglobulin classes identified genetic signatures involved with reactive oxygen species generation, phagolysosome maturation and rupture, free iron availability, Th1/Th2 differenciation and, immunoglobulin clearance. The findings demonstrated the roles of the antibody response as resistance or susceptibility markers and mediators of CanL pathogenesis. In addition we pinpointed candidate genes as potential targets for the therapy against the damage caused by exacerbated antibody response and parasitism in VL.
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Affiliation(s)
- Luís F S Batista
- Laboratório De Patologia De Doenças Infecciosas, Faculdade De Medicina, Universidade De São Paulo, São Paulo, CEP: 01246903, Brazil.
| | - Rafaela B P Torrecilha
- Departamento De Medicina Veterinária Preventiva e Reprodução Animal, Faculdade De Ciências Agrárias e Veterinárias, Univ Estadual Paulista, Jaboticabal, São Paulo, CEP: 14884-900, Brazil.
| | - Rafaela B Silva
- Escola de Saúde, Universidade Salvador, Salvador, Bahia, CEP: 41720-200, Brazil.
| | - Yuri T Utsunomiya
- Departamento de Apoio, Produção e Saúde Animal, Faculdade de Medicina Veterinária de Araçatuba, Univ Estadual Paulista, Araçatuba, São Paulo, CEP: 16015-050, Brazil.
| | - Thaís B F Silva
- Laboratório De Patologia De Doenças Infecciosas, Faculdade De Medicina, Universidade De São Paulo, São Paulo, CEP: 01246903, Brazil.
| | - Thaíse Y Tomokane
- Laboratório De Patologia De Doenças Infecciosas, Faculdade De Medicina, Universidade De São Paulo, São Paulo, CEP: 01246903, Brazil.
| | - Acácio D Pacheco
- Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Univ Estadual Paulista, Araçatuba, São Paulo, CEP: 16015-050, Brazil.
| | - Anelise M Bosco
- Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Univ Estadual Paulista, Araçatuba, São Paulo, CEP: 16015-050, Brazil.
| | - Silvana C Paulan
- Departamento de Apoio, Produção e Saúde Animal, Faculdade de Medicina Veterinária de Araçatuba, Univ Estadual Paulista, Araçatuba, São Paulo, CEP: 16015-050, Brazil.
| | - Claudio N Rossi
- Departamento de Clínica, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, CEP 05508-270, Brazil.
| | - Gustavo N O Costa
- Departamento De Medicina Veterinária Preventiva e Reprodução Animal, Faculdade De Ciências Agrárias e Veterinárias, Univ Estadual Paulista, Jaboticabal, São Paulo, CEP: 14884-900, Brazil.
| | - Mary Marcondes
- Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Univ Estadual Paulista, Araçatuba, São Paulo, CEP: 16015-050, Brazil.
| | - Paulo C Ciarlini
- Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Univ Estadual Paulista, Araçatuba, São Paulo, CEP: 16015-050, Brazil.
| | - Cáris M Nunes
- Departamento de Apoio, Produção e Saúde Animal, Faculdade de Medicina Veterinária de Araçatuba, Univ Estadual Paulista, Araçatuba, São Paulo, CEP: 16015-050, Brazil.
| | - Vânia L R Matta
- Laboratório De Patologia De Doenças Infecciosas, Faculdade De Medicina, Universidade De São Paulo, São Paulo, CEP: 01246903, Brazil.
| | - Márcia D Laurenti
- Laboratório De Patologia De Doenças Infecciosas, Faculdade De Medicina, Universidade De São Paulo, São Paulo, CEP: 01246903, Brazil.
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Sumayao R, Newsholme P, McMorrow T. The Role of Cystinosin in the Intermediary Thiol Metabolism and Redox Homeostasis in Kidney Proximal Tubular Cells. Antioxidants (Basel) 2018; 7:antiox7120179. [PMID: 30513914 PMCID: PMC6315507 DOI: 10.3390/antiox7120179] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/22/2018] [Accepted: 11/24/2018] [Indexed: 01/26/2023] Open
Abstract
Cystinosin is a lysosomal transmembrane protein which facilitates transport of the disulphide amino acid cystine (CySS) from the lysosomes of the cell. This protein is encoded by the CTNS gene which is defective in the lysosomal storage disorder, cystinosis. Because of the apparent involvement of cystinosin in the intermediary thiol metabolism, its discovery has fuelled investigations into its role in modulating cellular redox homeostasis. The kidney proximal tubular cells (PTCs) have become the focus of various studies on cystinosin since the protein is highly expressed in these cells and kidney proximal tubular transport dysfunction is the foremost clinical manifestation of cystinosis. The lysosomal CySS pool is a major source of cytosolic cysteine (Cys), the limiting amino acid for the synthesis of an important antioxidant glutathione (GSH) via the γ-glutamyl cycle. Therefore, loss of cystinosin function is presumed to lead to cytosolic deficit of Cys which may impair GSH synthesis. However, studies using in vitro models lacking cystinosin yielded inconsistent results and failed to establish the mechanistic role of cystinosin in modulating GSH synthesis and redox homeostasis. Because of the complexity of the metabolic micro- and macro-environment in vivo, using in vitro models alone may not be able to capture the complete sequence of biochemical and physiological events that occur as a consequence of loss of cystinosin function. The coexistence of pathways for the overall handling and disposition of GSH, the modulation of CTNS gene by intracellular redox status and the existence of a non-canonical isoform of cystinosin may constitute possible rescue mechanisms in vivo to remediate redox perturbations in renal PTCs. Importantly, the mitochondria seem to play a critical role in orchestrating redox imbalances initiated by cystinosin dysfunction. Non-invasive techniques such as in vivo magnetic resonance imaging with the aid of systems biology approaches may provide invaluable mechanistic insights into the role of cystinosin in the essential intermediary thiol metabolism and in the overall regulation cellular redox homeostasis.
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Affiliation(s)
- Rodolfo Sumayao
- Chemistry Department, De La Salle University, Manila 1004, Philippines.
| | - Philip Newsholme
- School of Pharmacy and Biomedical Sciences and Curtin Health Innovation Research Institute (CHIRI), Curtin University, Perth 6845, Australia.
| | - Tara McMorrow
- Conway Institute, School of Biomolecular and Biomedical Science, University College Dublin, Dublin 4, Ireland.
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Deshpande AA, Shukla A, Bachhawat AK. A Genetic Screen for Investigating the Human Lysosomal CystineTransporter, Cystinosin. Sci Rep 2018; 8:3442. [PMID: 29467429 PMCID: PMC5821828 DOI: 10.1038/s41598-018-21483-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 02/06/2018] [Indexed: 11/09/2022] Open
Abstract
Cystinosin, a lysosomal transporter is involved in the efflux of cystine from the lysosome to the cytosol. Mutations in the human cystinosin gene (CTNS) cause cystinosis, a recessive autosomal disorder. Studies on cystinosin have been limited by the absence of a robust genetic screen. In the present study we have developed a dual strategy for evaluating cystinosin function that is amenable to rapid genetic analysis. We show that human cystinosin expressed in this yeast confers growth on cystine when the protein is mistargeted to the plasma membrane by the deletion of the C-terminal targeting signal, GYQDL. We also screened a vacuolar protein sorting deletion library, and subsequently created multiple vps deletion mutants for kinetic studies. The double deletion, vps1Δvps17Δ, greatly enhanced uptake. This enabled validation by kinetic studies, including first studies on the WT CTNS protein (that contained the GYQDL motif). Using this screen we isolated several gain of function mutants, G131S/D, G309S/D, A137V, G197R, S270T, L274F and S312N showing enhanced growth on low concentrations of cystine. Kinetic analysis yielded insights into the role of the residues (including one of the patient mutations, G197R). The results indicate that the screen could be effectively used for interrogating and understanding the CTNS protein.
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Affiliation(s)
- Anup Arunrao Deshpande
- Indian Institute of Science and Education Research Mohali, Sector 81, Knowledge City, SAS Nagar, Punjab, India
| | - Anuj Shukla
- Indian Institute of Science and Education Research Mohali, Sector 81, Knowledge City, SAS Nagar, Punjab, India
| | - Anand Kumar Bachhawat
- Indian Institute of Science and Education Research Mohali, Sector 81, Knowledge City, SAS Nagar, Punjab, India.
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Cystinosin-LKG rescues cystine accumulation and decreases apoptosis rate in cystinotic proximal tubular epithelial cells. Pediatr Res 2017; 81:113-119. [PMID: 27656773 DOI: 10.1038/pr.2016.184] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 08/10/2016] [Indexed: 01/19/2023]
Abstract
BACKGROUND Nephropathic cystinosis is a lysosomal storage disease that is caused by mutations in the CTNS gene encoding a cystine/proton symporter cystinosin and an isoform cystinosin-LKG which is generated by an alternative splicing of exon 12. We have investigated the physiological role of the cystinosin-LKG that is widely expressed in epithelial tissues. METHODS We have analyzed the intracellular localization and the function of the cystinosin-LKG conjugated with DsRed (cystinosin-LKG-RFP) in Madin-Darby canine kidney cells (MDCK II) and in proximal tubular epithelial cells carrying a deletion of the CTNS gene (cystinotic PTEC), respectively. RESULTS Cystinosin-LKG-RFP colocalized with markers of lysosomes, late endosomes and was also expressed on the apical surface of polarized MDCK II cells. Moreover, immune-electron microscopy images of MDCK II cells overexpressing cystinosin-LKG-RFP showed stacked lamellar membranes inside perinuclear lysosomal structures. To study the role of LKG-isoform, we have investigated cystine accumulation and apoptosis that have been described in cystinotic cells. Cystinosin-LKG decreased cystine levels by approximately 10-fold similarly to cystinosin-RFP. The levels of TNFα- and actinomycin D-inducted apoptosis dropped in cystinotic cells expressing LKG-isoform. This effect was also similar to the main isoform. CONCLUSION Our results suggest that cystinosin-LKG and cystinosin move similar functional activities in cells.
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Cherqui S, Courtoy PJ. The renal Fanconi syndrome in cystinosis: pathogenic insights and therapeutic perspectives. Nat Rev Nephrol 2016; 13:115-131. [PMID: 27990015 DOI: 10.1038/nrneph.2016.182] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cystinosis is an autosomal recessive metabolic disease that belongs to the family of lysosomal storage disorders. It is caused by a defect in the lysosomal cystine transporter, cystinosin, which results in an accumulation of cystine in all organs. Despite the ubiquitous expression of cystinosin, a renal Fanconi syndrome is often the first manifestation of cystinosis, usually presenting within the first year of life and characterized by the early and severe dysfunction of proximal tubule cells, highlighting the unique vulnerability of this cell type. The current therapy for cystinosis, cysteamine, facilitates lysosomal cystine clearance and greatly delays progression to kidney failure but is unable to correct the Fanconi syndrome. This Review summarizes decades of studies that have fostered a better understanding of the pathogenesis of the renal Fanconi syndrome associated with cystinosis. These studies have unraveled some of the early molecular changes that occur before the onset of tubular atrophy and identified a role for cystinosin beyond cystine transport, in endolysosomal trafficking and proteolysis, lysosomal clearance, autophagy and the regulation of energy balance. These studies have also led to the identification of new potential therapeutic targets and here, we outline the potential role of stem cell therapy for cystinosis and provide insights into the mechanism of haematopoietic stem cell-mediated kidney protection.
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Affiliation(s)
- Stephanie Cherqui
- Department of Pediatrics, Division of Genetics, University of California San Diego, 9500 Gilman Drive, MC 0734, La Jolla, California 92093-0734, USA
| | - Pierre J Courtoy
- Cell biology, de Duve Institute and Université catholique de Louvain, UCL-Brussels, 75 Avenue Hippocrate, B-1200 Brussels, Belgium
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