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Lourenço CM, Sallum JMF, Pereira AM, Girotto PN, Kok F, Vilela DRF, Barron E, Pessoa A, Oliveira BMD. A needle in a haystack? The impact of a targeted epilepsy gene panel in the identification of a treatable but rapidly progressive metabolic epilepsy: CLN2 disease. ARQUIVOS DE NEURO-PSIQUIATRIA 2024; 82:1-8. [PMID: 38763144 PMCID: PMC11102811 DOI: 10.1055/s-0044-1786854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 03/30/2024] [Indexed: 05/21/2024]
Abstract
BACKGROUND Neuronal ceroid lipofuscinoses (NCL) are a group of autosomal recessive, inherited, lysosomal, and neurodegenerative diseases that causes progressive dementia, seizures, movement disorders, language delay/regression, progressive visual failure, and early death. Neuronal ceroid lipofuscinosis type 2 (CLN2), caused by biallelic pathogenic variants of the TPP1 gene, is the only NCL with an approved targeted therapy. The laboratory diagnosis of CLN2 is established through highly specific tests, leading to diagnostic delays and eventually hampering the provision of specific treatment for patients with CLN2. Epilepsy is a common and clinically-identifiable feature among NCLs, and seizure onset is the main driver for families to seek medical care. OBJECTIVE To evaluate the results of the Latin America Epilepsy and Genetics Program, an epilepsy gene panel, as a comprehensive tool for the investigation of CLN2 among other genetic causes of epilepsy. METHODS A total of 1,284 patients with epilepsy without a specific cause who had at least 1 symptom associated with CLN2 were screened for variants in 160 genes associated with epilepsy or metabolic disorders presenting with epilepsy through an epilepsy gene panel. RESULTS Variants of the TPP1 gene were identified in 25 individuals (1.9%), 21 of them with 2 variants. The 2 most frequently reported variants were p.Arg208* and p.Asp276Val, and 2 novel variants were detected in the present study: p.Leu308Pro and c.89 + 3G > C Intron 2. CONCLUSION The results suggest that these genetic panels can be very useful tools to confirm or exclude CLN2 diagnosis and, if confirmed, provide disease-specific treatment for the patients.
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Affiliation(s)
| | - Juliana Maria Ferraz Sallum
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Departamento de Oftalmologia e Ciências Visuais, São Paulo SP, Brazil.
| | | | | | - Fernando Kok
- Mendelics Análise Genômica, São Paulo SP, Brazil.
| | | | - Erika Barron
- BioMarin Brasil Farmacêutica Ltda., São Paulo SP, Brazil.
| | - André Pessoa
- Hospital Albert Sabin, Fortaleza CE, Brazil.
- Universidade Estadual do Ceará, Fortaleza CE, Brazil.
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Guelbert N, Espitia Segura OM, Amoretti C, Arteaga Arteaga A, Atanacio NG, Bazan Natacha S, Carvalho EDF, Carvalho de Andrade MDF, Denzler IM, Durand C, Ribeiro E, Giugni JC, González G, González Moron D, Guelbert G, Hernández Rodriguez ZJ, Embiruçu Emilia K, Kauffman MA, Mancilla NI, Marcon L, Marques Pereira A, Fischinger Moura de Souza C, Muñoz VA, Naranjo Flórez RA, Pessoa AL, Ruiz MV, Solano Villareal ML, Spécola N, Tavera LM, Tello J, Troncoso Schifferli M, Ugrina S, Vaccarezza MM, Vergara D, Villanueva MM. Classic and Atypical Late Infantile Neuronal Ceroid Lipofuscinosis in Latin America: Clinical and Genetic Aspects, and Treatment Outcome with Cerliponase Alfa. Mol Genet Metab Rep 2024; 38:101060. [PMID: 38469103 PMCID: PMC10926189 DOI: 10.1016/j.ymgmr.2024.101060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 01/12/2024] [Accepted: 01/20/2024] [Indexed: 03/13/2024] Open
Abstract
Introduction Late infantile neuronal ceroid lipofuscinosis type 2 (CLN2), is a neurodegenerative autosomal recessive disease caused by TPP1 gene variants, with a spectrum of classic and atypical phenotypes. The aim of treatment is to slow functional decline as early as possible in an attempt to improve quality of life and survival. This study describes the clinical characteristics as well as the response to treatment with cerliponase alfa. Materials and methods A retrospective study was conducted in five Latin-American countries, using clinical records from patients with CLN2. Clinical follow-up and treatment variables are described. A descriptive and bivariate statistical analysis was performed. Results A total of 36 patients were observed (range of follow-up of 61-110 weeks post-treatment). At presentation, patients with the classic phenotype (n = 16) exhibited regression in language (90%), while seizures were the predominant symptom (87%) in patients with the atypical phenotype (n = 20). Median age of symptom onset and time to first specialized consultation was 3 (classical) and 7 (atypical) years, while the median time interval between onset of symptoms and treatment initiation was 4 years (classical) and 7.5 (atypical). The most frequent variant was c.827 A > T in 17/72 alleles, followed by c.622C > T in 6/72 alleles. All patients were treated with cerliponase alfa, and either remained functionally stable or had a loss of 1 point on the CLN2 scale, or up to 2 points on the Wells Cornel and Hamburg scales, when compared to pretreatment values. Discussion and conclusion This study reports the largest number of patients with CLN2 currently on treatment with cerliponase alfa in the world. Data show a higher frequency of patients with atypical phenotypes and a high allelic proportion of intron variants in our region. There was evidence of long intervals until first specialized consultation, diagnosis, and enzyme replacement therapy. Follow-up after the initiation of cerliponase alfa showed slower progression or stabilization of the disease, associated with adequate clinical outcomes and stable functional scores. These improvements were consistent in both clinical phenotypes.
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Affiliation(s)
| | | | | | | | | | | | | | - Maria Denise Fernandes Carvalho de Andrade
- Christus University Center (UNICHRISTUS), Fortaleza, Brazil
- General Hospital Dr. Cesar Cals, Fortaleza, Brazil
- Universidade Estadual do Ceará (UECE), Fortaleza, Brazil
- Hospital Universitário do Ceará, Fortaleza, Brazil
- Faculdadde Paulo Picanço, Fortaleza, Brazil
| | - Inés María Denzler
- Hospital Italiano de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Consuelo Durand
- Laboratorio de Neuroquímica Dr. N.A. Chamoles, Ciudad Autónoma de Buenos Aires, Argentina
| | | | | | | | | | | | | | | | | | | | - Laureano Marcon
- Instituto de Neurología y desarrollo (INEDEM), Buenos Aires, Argentina
| | | | | | | | | | | | | | | | - Norma Spécola
- Hospital de Niños Sor Maria Ludovica, La Plata, Argentina
| | | | - Javiera Tello
- Hospital Clínico San Borja Arriarán, Santiago, Chile
- Universidad de Chile, Santiago, Chile
| | | | | | | | - Diane Vergara
- Hospital Clínico San Borja Arriarán, Santiago, Chile
- Universidad de Chile, Santiago, Chile
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Vafaei N, Mohebbi A, Rezaei Z, Heidari M, Hosseinpour S, Dehnavi AZ, Ghamari A, Salehipour M, Rabbani A, Mahdieh N, Ashrafi MR. TPP1 Variants in Iranian patients: A Novel Pathogenic Homozygous Variant Causing Neuronal Ceroid Lipofuscinosis 2. Mol Syndromol 2024; 15:30-36. [PMID: 38357261 PMCID: PMC10862320 DOI: 10.1159/000534100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 09/11/2023] [Indexed: 02/16/2024] Open
Abstract
Introduction TPP1 variants have been identified as a causative agent of neuronal ceroid lipofuscinosis 2 disease, that ataxia is one of its clinical features. Therefore, here, molecular study of TPP1 variants is presented in an Iranian cohort and a novel pathogenic variant is described. Methods This investigation was conducted as a cross-sectional study in a tertiary referral hospital, Children's Medical Center, Pediatrics Center of Excellence. Clinical presentations and pedigrees were documented. Patients with cerebellar ataxia were enrolled in this study. Next-generation sequencing was applied to confirm the diagnosis. Segregation and bioinformatics analyses were also done for the variants using Sanger sequencing. Results Forty-five patients were included in our study. The mean age of onset was 104 (+55.60) months (minimum = 31 months, maximum = 216 months). The majority of cases (73.3%) were born to consanguineous parents and only 1 patient (2.2%) had an affected sibling. Of the 45 patients, only 1 patient with a novel pathogenic variant (c.1425_1425+1delinsAT, p.A476Cfs*15) in the TPP1 gene was identified. Discussion The main strength of current study is the relatively large sample size. Besides, a novel pathogenic variant could be important toward the diagnosis and management of this condition. With significant advances in various therapies, early diagnosis could improve the treatments using personalized-based medicine.
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Affiliation(s)
- Nahid Vafaei
- Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali Mohebbi
- Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Zahra Rezaei
- Pediatrics Center of Excellence, Department of Pediatric Neurology, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Morteza Heidari
- Pediatric Neurology Division, Children’s Medical Center, Pediatrics Center of Excellence, Myelin Disorders Clinic, Tehran University of Medical Sciences, Tehran, Iran
| | - Sareh Hosseinpour
- Pediatrics Center of Excellence, Department of Pediatric Neurology, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali Zare Dehnavi
- Pediatrics Center of Excellence, Department of Pediatric Neurology, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - Azin Ghamari
- Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Masoud Salehipour
- Department of Biology, Parand Branch, Islamic Azad University, Parand, Iran
| | - Ali Rabbani
- Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Nejat Mahdieh
- Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
- Cardiogenetic Research Center, Rajaie Cardiovascular, Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mahmoud Reza Ashrafi
- Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
- Pediatrics Center of Excellence, Department of Pediatric Neurology, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran
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Ashaat EA, Ahmed HA, Elaraby NM, Fayez A, Metwally AM, Mekkawy MK, Hussen DF, Ashaat NA, Elhossini RM, ElAwady HA, Abdelgawad RHA, Gammal ME, Al Kersh MA, Saleh DA. The Diagnostic Value of Whole-Exome Sequencing in a Spectrum of Rare Neurological Disorders Associated with Cerebellar Atrophy. Mol Neurobiol 2023:10.1007/s12035-023-03866-y. [PMID: 38153683 DOI: 10.1007/s12035-023-03866-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 12/08/2023] [Indexed: 12/29/2023]
Abstract
Several neurological disorders, neurodevelopmental disorders, and neurodegenerative disorders have a genetic element with various clinical presentations ranging from mild to severe presentation. Neurological disorders are rare multifactorial disorders characterized by dysfunction and degeneration of synapses, neurons, and glial cells which are essential for movement, coordination, muscle strength, sensation, and cognition. The cerebellum might be involved at any time, either during development and maturation or later in life. Herein, we describe a spectrum of NDDs and NDs in seven patients from six Egyptian families. The core clinical and radiological features of our patients included dysmorphic features, neurodevelopmental delay or regression, gait abnormalities, skeletal deformities, visual impairment, seizures, and cerebellar atrophy. Previously unreported clinical phenotypic findings were recorded. Whole-exome sequencing (WES) was performed followed by an in silico analysis of the detected genetic variants' effect on the protein structure. Three novel variants were identified in three genes MFSD8, AGTPBP1, and APTX, and other previously reported three variants have been detected in "TPP1, AGTPBP1, and PCDHGC4" genes. In this cohort, we described the detailed unique phenotypic characteristics given the identified genetic profile in patients with neurological "neurodevelopmental disorders and neurodegenerative disorders" disorders associated with cerebellar atrophy, hence expanding the mutational spectrum of such disorders.
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Affiliation(s)
- Engy A Ashaat
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt.
| | - Hoda A Ahmed
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Nesma M Elaraby
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Alaaeldin Fayez
- Molecular Genetics and Enzymology Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Ammal M Metwally
- Community Medicine Research Department, Medical Research and Clinical Studies Institute, National Research Centre, Cairo, Egypt
| | - Mona K Mekkawy
- Human Cytogenetic Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Dalia Farouk Hussen
- Human Cytogenetic Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | | | - Rasha M Elhossini
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | | | | | - Mona El Gammal
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | | | - Dina Amin Saleh
- Pediatric Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
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Steigerwald C, Borsuk J, Pappas J, Galey M, Scott A, Devaney JM, Miller DE, Abreu NJ. CLN2 disease resulting from a novel homozygous deep intronic splice variant in TPP1 discovered using long-read sequencing. Mol Genet Metab 2023; 140:107713. [PMID: 37922835 DOI: 10.1016/j.ymgme.2023.107713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 10/22/2023] [Indexed: 11/07/2023]
Abstract
Neuronal ceroid lipofuscinosis type 2 (CLN2) is an autosomal recessive neurodegenerative disorder with enzyme replacement therapy available. We present two siblings with a clinical diagnosis of CLN2 disease, but no identifiable TPP1 variants after standard clinical testing. Long-read sequencing identified a homozygous deep intronic variant predicted to affect splicing, confirmed by clinical DNA and RNA sequencing. This case demonstrates how traditional laboratory assays can complement emerging molecular technologies to provide a precise molecular diagnosis.
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Affiliation(s)
- Connolly Steigerwald
- Division of Neurogenetics, Department of Neurology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Jill Borsuk
- Division of Clinical Genetics, Department of Pediatrics, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - John Pappas
- Division of Clinical Genetics, Department of Pediatrics, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Miranda Galey
- Division of Genetic Medicine, Department of Pediatrics, University of Washington and Seattle Children's Hospital, Seattle, WA 98195, USA
| | - Anna Scott
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA; Department of Laboratories, Seattle Children's Hospital, Seattle, WA 08105, USA
| | | | - Danny E Miller
- Division of Genetic Medicine, Department of Pediatrics, University of Washington and Seattle Children's Hospital, Seattle, WA 98195, USA; Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA; Brotman Baty Institute for Precision Medicine, University of Washington, Seattle, WA 98195, USA
| | - Nicolas J Abreu
- Division of Neurogenetics, Department of Neurology, NYU Grossman School of Medicine, New York, NY 10016, USA.
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De BP, Rosenberg JB, Selvan N, Wilson I, Yusufzai N, Greco A, Kaminsky SM, Heier LA, Ricart Arbona RJ, Miranda IC, Monette S, Nair A, Khanna R, Crystal RG, Sondhi D. Assessment of Safety and Biodistribution of AAVrh.10hCLN2 Following Intracisternal Administration in Nonhuman Primates for the Treatment of CLN2 Batten Disease. Hum Gene Ther 2023; 34:905-916. [PMID: 37624739 PMCID: PMC10517331 DOI: 10.1089/hum.2023.067] [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: 04/24/2023] [Accepted: 06/10/2023] [Indexed: 08/27/2023] Open
Abstract
CLN2 disease is a fatal, childhood autosomal recessive disorder caused by mutations in ceroid lipofuscinosis type 2 (CLN2) gene, encoding tripeptidyl peptidase 1 (TPP-1). Loss of TPP-1 activity leads to accumulation of storage material in lysosomes and resultant neuronal cell death with neurodegeneration. Genotype/phenotype comparisons suggest that the phenotype should be ameliorated with increase of TPP-1 levels to 5-10% of normal with wide central nervous system (CNS) distribution. Our previous clinical study showed that intraparenchymal (IPC) administration of AAVrh.10hCLN2, an adeno-associated vector serotype rh.10 encoding human CLN2, slowed, but did not stop disease progression, suggesting that this may be insufficient to distribute the therapy throughout the CNS (Sondhi 2020). In this study, we assessed whether the less invasive intracisternal delivery route would be safe and provide a wider distribution of TPP-1. A study was conducted in nonhuman primates (NHPs) with intracisternal delivery to cerebrospinal fluid (CSF) of AAVrh.10hCLN2 (5 × 1013 genome copies) or phosphate buffered saline (PBS). No abnormal behavior was noted. CNS magnetic resonance imaging and clinical chemistry data were all unremarkable. Histopathology of major organs had no abnormal finding attributable to the intervention or the vector, except that in one out of two animals treated with AAVrh.10hCLN2, dorsal root ganglia showed mild-to-moderate mononuclear cell infiltrates and neuronal degeneration. In contrast to our previous NHP study (Sondhi 2012) with IPC administration where TPP-1 activity was >2 × above controls in 30% of treated brains, in the two intracisternal treated NHPs, the TPP-1 activity was >2 × above controls in 50% and 41% of treated brains, and 52% and 84% of brain had >1,000 vector genomes/μg DNA, compared to 0% in the two PBS NHP. CSF TPP1 levels in treated animals were 43-62% of normal human levels. Collectively, these data indicate that AAVrh.10hCLN2 delivered by intracisternal route is safe and widely distributes TPP-1 in brain and CSF at levels that are potentially therapeutic. Clinical Trial Registration: NCT02893826, NCT04669535, NCT04273269, NCT03580083, NCT04408625, NCT04127578, and NCT04792944.
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Affiliation(s)
- Bishnu P. De
- Department of Genetic Medicine, New York, New York, USA
| | | | | | | | | | | | | | - Linda A. Heier
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - Rodolfo J. Ricart Arbona
- Center for Comparative Medicine and Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, New York, New York, USA
| | - Ileana C. Miranda
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, The Rockefeller University, Weill Cornell Medicine, New York, New York, USA
| | - Sebastien Monette
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, The Rockefeller University, Weill Cornell Medicine, New York, New York, USA
| | - Anju Nair
- LEXEO Therapeutics, New York, New York, USA
| | | | | | - Dolan Sondhi
- Department of Genetic Medicine, New York, New York, USA
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Munesue Y, Ageyama N, Kimura N, Takahashi I, Nakayama S, Okabayashi S, Katakai Y, Koie H, Yagami KI, Ishii K, Tamaoka A, Yasutomi Y, Shimozawa N. Cynomolgus macaque model of neuronal ceroid lipofuscinosis type 2 disease. Exp Neurol 2023; 363:114381. [PMID: 36918063 DOI: 10.1016/j.expneurol.2023.114381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 03/06/2023] [Accepted: 03/09/2023] [Indexed: 03/14/2023]
Abstract
Neuronal ceroid lipofuscinoses (NCLs) are autosomal-recessive fatal neurodegenerative diseases that occur in children and young adults, with symptoms including ataxia, seizures and visual impairment. We report the discovery of cynomolgus macaques carrying the CLN2/TPP1 variant and our analysis of whether the macaques could be a new non-human primate model for NCL type 2 (CLN2) disease. Three cynomolgus macaques presented progressive neuronal clinical symptoms such as limb tremors and gait disturbance after about 2 years of age. Morphological analyses using brain MRI at the endpoint of approximately 3 years of age revealed marked cerebellar and cerebral atrophy of the gray matter, with sulcus dilation, gyrus thinning, and ventricular enlargement. Histopathological analyses of three affected macaques revealed severe neuronal loss and degeneration in the cerebellar and cerebral cortices, accompanied by glial activation and/or changes in axonal morphology. Neurons observed throughout the central nervous system contained autofluorescent cytoplasmic pigments, which were identified as ceroid-lipofuscin based on staining properties, and the cerebral cortex examined by transmission electron microscopy had curvilinear profiles, the typical ultrastructural pattern of CLN2. These findings are commonly observed in all forms of NCL. DNA sequencing analysis identified a homozygous single-base deletion (c.42delC) of the CLN2/TPP1 gene, resulting in a frameshifted premature stop codon. Immunohistochemical analysis showed that tissue from the affected macaques lacked a detectable signal against TPP1, the product of the CLN2/TPP1 gene. Analysis for transmission of the CLN2/TPP1 mutated gene revealed that 47 (49.5%) and 48 (50.5%) of the 95 individuals genotyped in the CLN2-affected macaque family were heterozygous carriers and homozygous wild-type individuals, respectively. Thus, we identified cynomolgus macaques as a non-human primate model of CLN2 disease. The CLN2 macaques reported here could become a useful resource for research and the development of drugs and methods for treating CLN2 disease, which involves severe symptoms in humans.
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Affiliation(s)
- Yoshiko Munesue
- Division of Clinical Medicine, Department of Neurology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Naohide Ageyama
- Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, 1-1 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan
| | - Nobuyuki Kimura
- Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, 1-1 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan; Department of Veterinary Associated Science, Faculty of Veterinary Medicine, Okayama University of Science, 1-3 Ikoinooka, Imabari, Ehime 794-8555, Japan
| | - Ichiro Takahashi
- Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, 1-1 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan
| | - Shunya Nakayama
- Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, 1-1 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan; Laboratory of Veterinary Physiology/Pathophysiology, Nihon University, College of Bioresource Science, 1866 Kameino, Fujisawa, Kanagawa 252-0880, Japan
| | - Sachi Okabayashi
- The Corporation for Production and Research of Laboratory Primates, 1-16-2 Sakura, Tsukuba, Ibaraki 305-0843, Japan
| | - Yuko Katakai
- The Corporation for Production and Research of Laboratory Primates, 1-16-2 Sakura, Tsukuba, Ibaraki 305-0843, Japan
| | - Hiroshi Koie
- Laboratory of Veterinary Physiology/Pathophysiology, Nihon University, College of Bioresource Science, 1866 Kameino, Fujisawa, Kanagawa 252-0880, Japan
| | - Ken-Ichi Yagami
- Laboratory Animal Resource Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Kazuhiro Ishii
- Division of Clinical Medicine, Department of Neurology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Akira Tamaoka
- Division of Clinical Medicine, Department of Neurology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Yasuhiro Yasutomi
- Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, 1-1 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan; Department of Molecular and Experimental Medicine, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan
| | - Nobuhiro Shimozawa
- Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, 1-1 Hachimandai, Tsukuba, Ibaraki 305-0843, Japan.
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Sampaio LPDB, Manreza MLGD, Pessoa A, Gurgel-Giannetti J, Coan AC, Júnior HVDL, Embiruçu EK, Henriques-Souza AMDM, Kok F. Clinical management and diagnosis of CLN2 disease: consensus of the Brazilian experts group. ARQUIVOS DE NEURO-PSIQUIATRIA 2023; 81:284-295. [PMID: 37059438 PMCID: PMC10104757 DOI: 10.1055/s-0043-1761434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Neuronal ceroid lipofuscinosis type 2 (CLN2) is a rare neurodegenerative genetic disease that affects children in early life. Its classic form is rapidly progressive, leading to death within the first 10 years. The urge for earlier diagnosis increases with the availability of enzyme replacement therapy. A panel of nine Brazilian child neurologists combined their expertise in CLN2 with evidence from the medical literature to establish a consensus to manage this disease in Brazil. They voted 92 questions including diagnosis, clinical manifestations, and treatment of the disease, considering the access to healthcare in this country. Clinicians should suspect CLN2 disease in any child, from 2 to 4 years old, with language delay and epilepsy. Even though the classic form is the most prevalent, atypical cases with different phenotypes can be found. Electroencephalogram, magnetic resonance imaging, molecular and biochemical testing are the main tools to investigate and confirm the diagnosis. However, we have limited access to molecular testing in Brazil, and rely on the support from the pharmaceutical industry. The management of CLN2 should involve a multidisciplinary team and focus on the quality of life of patients and on family support. Enzyme replacement therapy with Cerliponase α is an innovative treatment approved in Brazil since 2018; it delays functional decline and provides quality of life. Given the difficulties for the diagnosis and treatment of rare diseases in our public health system, the early diagnosis of CLN2 needs improvement as enzyme replacement therapy is available and modifies the prognosis of patients.
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Affiliation(s)
| | | | - André Pessoa
- Universidade Estadual do Ceará, Hospital Infantil Albert Sabin, Fortaleza CE, Brazil
| | - Juliana Gurgel-Giannetti
- Universidade Federal de Minas Gerais, Faculdade de Medicina, Hospital das Clínicas, Belo Horizonte MG, Brazil
| | - Ana Carolina Coan
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas, Campinas SP, Brazil
| | | | - Emília Katiane Embiruçu
- Universidade do Estado da Bahia, Hospital Universitário Professor Edgard Santos, Salvador BA, Brazil
| | | | - Fernando Kok
- Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, São Paulo SP, Brazil
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Sivananthan S, Lee L, Anderson G, Csanyi B, Williams R, Gissen P. Buffy Coat Score as a Biomarker of Treatment Response in Neuronal Ceroid Lipofuscinosis Type 2. Brain Sci 2023; 13:209. [PMID: 36831752 PMCID: PMC9954623 DOI: 10.3390/brainsci13020209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/19/2023] [Accepted: 01/22/2023] [Indexed: 01/28/2023] Open
Abstract
The introduction of intracerebroventricular (ICV) enzyme replacement therapy (ERT) for treatment of neuronal ceroid lipofuscinosis type 2 (CLN2) disease has produced dramatic improvements in disease management. However, assessments of therapeutic effect for ICV ERT are limited to clinical observational measures, namely the CLN2 Clinical Rating Scale, a subjective measure of motor and language performance. There is a need for an objective biomarker to enable assessments of disease progression and response to treatment. To address this, we investigated whether the proportion of cells with abnormal storage inclusions on electron microscopic examination of peripheral blood buffy coats could act as a biomarker of disease activity in CLN2 disease. We conducted a prospective longitudinal analysis of six patients receiving ICV ERT. We demonstrated a substantial and continuing reduction in the proportion of abnormal cells over the course of treatment, whereas symptomatic scores revealed little or no change over time. Here, we proposed the use of the proportion of cells with abnormal storage as a biomarker of response to therapy in CLN2. In the future, as more tissue-specific biomarkers are developed, the buffy coats may form part of a panel of biomarkers in order to give a more holistic view of a complex disease.
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Affiliation(s)
- Siyamini Sivananthan
- Department of Inherited Metabolic Diseases, Great Ormond Street Hospital, London WC1N 1EH, UK
| | - Laura Lee
- Department of Inherited Metabolic Diseases, Great Ormond Street Hospital, London WC1N 1EH, UK
| | - Glenn Anderson
- Department of Inherited Metabolic Diseases, Great Ormond Street Hospital, London WC1N 1EH, UK
- Institute for Health Research Great Ormond Street Hospital Biomedical Research Centre, University College London, London WC1N 1EH, UK
| | - Barbara Csanyi
- Department of Inherited Metabolic Diseases, Great Ormond Street Hospital, London WC1N 1EH, UK
| | - Ruth Williams
- Department of Children’s Neurosciences, Evelina London Children’s Hospital, London SE1 7EH, UK
| | - Paul Gissen
- Department of Inherited Metabolic Diseases, Great Ormond Street Hospital, London WC1N 1EH, UK
- Institute for Health Research Great Ormond Street Hospital Biomedical Research Centre, University College London, London WC1N 1EH, UK
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10
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Ho ML, Wirrell EC, Petropoulou K, Sakonju A, Chu D, Seratti G, Palasis S. Role of Electroencephalogram (EEG) and Magnetic Resonance Imaging (MRI) Findings in Early Recognition and Diagnosis of Neuronal Ceroid Lipofuscinosis Type 2 Disease. J Child Neurol 2022; 37:984-991. [PMID: 36184928 DOI: 10.1177/08830738221128773] [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] [Indexed: 11/15/2022]
Abstract
Neuronal ceroid lipofuscinosis type 2 (CLN2) disease is a very rare neurodegenerative lysosomal storage disorder. Progression is rapid and irreversible, making early diagnosis crucial for timely treatment. A group of pediatric neurologists and neuroradiologists with expertise in CLN2 convened to discuss early electroencephalogram (EEG) and magnetic resonance imaging (MRI) findings in CLN2 diagnosis. Of 18 CLN2 cases, 16 (88.9%) had background slowing and 16 (88.9%) had epileptiform discharges on initial EEG. Seven of 17 (41.2%) patients who received intermittent low-frequency photic stimulation had a photoparoxysmal response. Initial MRIs showed subtle cerebellar (n = 14, 77.8%) or cerebral (n = 9, 50.0%) atrophy, white matter abnormalities (n = 11, 61.1%), and basal ganglia T2 hypointensity (n = 6, 33.3%), which became more apparent on follow-up MRI. The recognition of even subtle cerebellar atrophy and white matter signal changes in children aged 2-5 years who present with language delay, new-onset seizures, and an EEG with epileptiform discharges and background slowing should prompt investigation for CLN2. Because these early signs are not unique to CLN2, genetic testing is essential early in the diagnostic journey.
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Affiliation(s)
- Mai-Lan Ho
- Nationwide Children's Hospital, Columbus, OH, USA
| | | | | | - Ai Sakonju
- 12302SUNY Upstate Medical University, Syracuse, NY, USA
| | - Dorna Chu
- 10926BioMarin Pharmaceutical Inc, Novato, CA, USA
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11
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Swier VJ, White KA, Johnson TB, Sieren JC, Johnson HJ, Knoernschild K, Wang X, Rohret FA, Rogers CS, Pearce DA, Brudvig JJ, Weimer JM. A Novel Porcine Model of CLN2 Batten Disease that Recapitulates Patient Phenotypes. Neurotherapeutics 2022; 19:1905-1919. [PMID: 36100791 PMCID: PMC9723024 DOI: 10.1007/s13311-022-01296-7] [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] [Accepted: 08/27/2022] [Indexed: 12/13/2022] Open
Abstract
CLN2 Batten disease is a lysosomal disorder in which pathogenic variants in CLN2 lead to reduced activity in the enzyme tripeptidyl peptidase 1. The disease typically manifests around 2 to 4 years of age with developmental delay, ataxia, seizures, inability to speak and walk, and fatality between 6 and 12 years of age. Multiple Cln2 mouse models exist to better understand the etiology of the disease; however, these models are unable to adequately recapitulate the disease due to differences in anatomy and physiology, limiting their utility for therapeutic testing. Here, we describe a new CLN2R208X/R208X porcine model of CLN2 disease. We present comprehensive characterization showing behavioral, pathological, and visual phenotypes that recapitulate those seen in CLN2 patients. CLN2R208X/R208X miniswine present with gait abnormalities at 6 months of age, ERG waveform declines at 6-9 months, vision loss at 11 months, cognitive declines at 12 months, seizures by 15 months, and early death at 18 months due to failure to thrive. CLN2R208X/R208X miniswine also showed classic storage material accumulation and glial activation in the brain at 6 months, and cortical atrophy at 12 months. Thus, the CLN2R208X/R208X miniswine model is a valuable resource for biomarker discovery and therapeutic development in CLN2 disease.
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Affiliation(s)
- Vicki J Swier
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA
| | - Katherine A White
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA
| | - Tyler B Johnson
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA
| | - Jessica C Sieren
- Department of Radiology, University of Iowa, Iowa City, IA, USA
- Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA
| | - Hans J Johnson
- Department of Electrical and Computer Engineering, University of Iowa, Iowa City, IA, USA
| | - Kevin Knoernschild
- Department of Radiology, University of Iowa, Iowa City, IA, USA
- Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA
| | | | | | | | - David A Pearce
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
| | - Jon J Brudvig
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
| | - Jill M Weimer
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA.
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA.
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12
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Miao SB, Guo H, Kong DX, Zhao YY, Pan SH, Jiang Y, Gao X, Wu XH. Case report: Analysis of novel compound heterozygous TPP1 variants in a Chinese patient with neuronal ceroid lipofuscinosis type 2. Front Genet 2022; 13:937485. [PMID: 36118858 PMCID: PMC9471087 DOI: 10.3389/fgene.2022.937485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
Neuronal ceroid lipofuscinosis type 2 (CLN2) is an autosomal recessive neurodegenerative disease caused by variants in the TPP1 gene that lead to the deficiency of the lysosomal enzyme tripeptidyl peptidase I (TPP1) activity. Herein, we report a rare case of CLN2 caused by two novel variants of TPP1. The patient presented with seizures at onset, followed by progressive cognitive impairment, motor decline, and vision loss. Novel compound heterozygous variants, c.544_545del and c.230-3C>G, in TPP1 were identified by whole-exome sequencing. The variant assessment showed that the c.544_545del is a frameshift variant mediating mRNA decay and that c.230-3C>G is a splice variant generating aberrantly spliced TPP1 mRNA, as confirmed by a Splicing Reporter Minigene assay. In conclusion, clinical history, variant assessment, and molecular analyses demonstrate that the novel compound heterozygous variants are responsible for CLN2 disease in this patient. This study expands the mutation spectrum of TPP1.
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Affiliation(s)
- Sui-Bing Miao
- Key Laboratory of Maternal and Fetal Medicine of Hebei Province, Institute of Reproductive Medicine of Shijiazhuang, The Fourth Hospital of Shijiazhuang Affiliated to Hebei Medical University, Shijiazhuang, China
| | - Hui Guo
- Department of Obstetrics and Gynecology, The Fourth Affiliated Hospital of Hebei Medical University Shijiazhuang, Shijiazhuang, China
| | - De-Xian Kong
- Department of Endocrinology, The Fourth Affiliated Hospital of Hebei Medical University Shijiazhuang, Shijiazhuang, China
| | - Yuan-Yuan Zhao
- Key Laboratory of Maternal and Fetal Medicine of Hebei Province, Institute of Reproductive Medicine of Shijiazhuang, The Fourth Hospital of Shijiazhuang Affiliated to Hebei Medical University, Shijiazhuang, China
| | - Shu-Hong Pan
- Key Laboratory of Maternal and Fetal Medicine of Hebei Province, Institute of Reproductive Medicine of Shijiazhuang, The Fourth Hospital of Shijiazhuang Affiliated to Hebei Medical University, Shijiazhuang, China
| | - Yan Jiang
- Center of Reproductive Medicine, The Fourth Hospital of Shijiazhuang Affiliated to Hebei Medical University, Shijiazhuang, China
| | - Xing Gao
- Center of Reproductive Medicine, The Fourth Hospital of Shijiazhuang Affiliated to Hebei Medical University, Shijiazhuang, China
| | - Xiao-Hua Wu
- Key Laboratory of Maternal and Fetal Medicine of Hebei Province, Institute of Reproductive Medicine of Shijiazhuang, The Fourth Hospital of Shijiazhuang Affiliated to Hebei Medical University, Shijiazhuang, China
- *Correspondence: Xiao-Hua Wu,
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13
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Atiskova Y, Wildner J, Wibbeler E, Nickel M, Spitzer MS, Schwering C, Schulz A, Dulz S. Visual perception and macular integrity in non-classical CLN2 disease. Graefes Arch Clin Exp Ophthalmol 2022; 260:3693-3700. [PMID: 35652945 PMCID: PMC9581810 DOI: 10.1007/s00417-022-05662-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/15/2022] [Accepted: 04/08/2022] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Patients with CLN2 suffer from epileptic seizures, rapid psychomotor decline and vision loss in early childhood. The aim of the study was to provide longitudinal ophthalmic data of patients with confirmed genetic mutation and non-classical disease course, marked by later onset, protracted progression and prolonged life span. METHODS Prospective, observational study to assess visual acuity, retinal features (Weil Cornell Ophthalmic Score), central retinal thickness (CRT) measured by optical coherence tomography and general disease progression (Hamburg CLN2 motor language score) in non-classical CLN2 patients. RESULTS All patients received intracerebroventricular enzyme replacement therapy with cerliponase alfa. Mean age at last follow-up was 12.4 years; mean follow-up time 2.6 years. All cases demonstrated a stable Hamburg motor language CLN2 Score and Weill Cornell LINCL Ophthalmic Severity Score. Visual function remained stable in 4/6 patients, 2/6 patients showed a decrease, 4/6 cases had a stable CRT and 2/6 showed a reduction of CRT. One patient showed a massive macular thinning and low vision. A correlation with a specific mutation or age could not be verified. DISCUSSION The presented longitudinal study characterizes the variable ocular involvement in non-classical CLN2 disease and contributes to the natural history description. The functional and morphologic data outline the necessity of regular ophthalmic examination. Ocular phenotyping and description of retinal degeneration in non-classical CLN2 disease.
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Affiliation(s)
- Yevgeniya Atiskova
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Jan Wildner
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Eva Wibbeler
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Miriam Nickel
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Martin Stephan Spitzer
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Christoph Schwering
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Angela Schulz
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Simon Dulz
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
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14
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Leal-Pardinas F, Truty R, McKnight DA, Johnson B, Morales A, Bristow SL, Pang TY, Cohen-Pfeffer J, Izzo E, Sankar R, Koh S, Wirrell EC, Millichap JJ, Aradhya S. Value of genetic testing for pediatric epilepsy: Driving earlier diagnosis of CLN2 Batten disease. Epilepsia 2022; 63:e68-e73. [PMID: 35474188 PMCID: PMC9545603 DOI: 10.1111/epi.17269] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 04/25/2022] [Accepted: 04/25/2022] [Indexed: 11/29/2022]
Abstract
This study assessed the effectiveness of genetic testing in shortening the time to diagnosis of late infantile neuronal ceroid lipofuscinosis type 2 (CLN2) disease. Individuals who received epilepsy gene panel testing through Behind the Seizure®, a sponsored genetic testing program (Cohort A), were compared to children outside of the sponsored testing program during the same period (Cohort B). Two cohorts were analyzed: children aged ≥24 to ≤60 months with unprovoked seizure onset at ≥24 months between December 2016 and January 2020 (Cohort 1) and children aged 0 to ≤60 months at time of testing with unprovoked seizure onset at any age between February 2019 and January 2020 (Cohort 2). The diagnostic yield in Cohort 1A (n = 1814) was 8.4% (n = 153). The TPP1 diagnostic yield within Cohort 1A was 2.9‐fold higher compared to Cohort 1B (1.0%, n = 18/1814 vs. .35%, n = 8/2303; p = .0157). The average time from first symptom to CLN2 disease diagnosis was significantly shorter than previously reported (9.8 vs. 22.7 months, p < .001). These findings indicate that facilitated access to early epilepsy gene panel testing helps to increase diagnostic yield for CLN2 disease and shortens the time to diagnosis, enabling earlier intervention.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Sookyong Koh
- University of Nebraska Medical Center, Omaha, NE, USA
| | | | - John J Millichap
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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15
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Nickel M, Schulz A. Natural History Studies in NCL and Their Expanding Role in Drug Development: Experiences From CLN2 Disease and Relevance for Clinical Trials. Front Neurol 2022; 13:785841. [PMID: 35211079 PMCID: PMC8861081 DOI: 10.3389/fneur.2022.785841] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 01/10/2022] [Indexed: 11/18/2022] Open
Abstract
Conducting clinical trials in rare diseases is challenging. In trials that aim to use natural history control cohorts for evaluation of efficacy, lack of data on natural history of disease prolongs development of future therapies significantly. Therefore, collection of valid natural history data in clinical settings is needed to advance drug development. These data need to fulfill requirements on type of collection, quantifiable measures on the course of disease, verification and monitoring as well as compliance to strict data protection and sharing policies. Disease registries can be a source for patient data. Late-infantile CLN2 disease is characterized by rapid psychomotor decline and epilepsy. Natural-history data of 140 genotype-confirmed CLN2 patients from two independent, international cohorts were analyzed in a natural history study. Both datasets included quantitative ratings with disease-specific clinical scores. Among 41 patients for whom longitudinal assessments spanning an extended disease course were available within the DEM-CHILD DB (an international NCL disease patient database, NCT04613089), a rapid loss of motor and language abilities was documented in quantitative detail. Data showed that the course of disease in late-infantile CLN2 disease is highly predictable with regard to the loss of language and motor function and that the results were homogeneous across multiple and international sites. These data were accepted by EMA and FDA as valid natural-history controls for the evaluation of efficacy in experimental therapies for CLN2 disease and led to an expedited approval of intracerebroventricular enzyme replacement therapy with cerliponase alpha in May 2017.
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Affiliation(s)
- Miriam Nickel
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Angela Schulz
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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16
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Mortensen A, Raebel EM, Wiseman S. Impact of the COVID-19 pandemic on access to the cerliponase alfa managed access agreement in England for CLN2 treatment. Orphanet J Rare Dis 2022; 17:19. [PMID: 35045884 PMCID: PMC8767529 DOI: 10.1186/s13023-021-02147-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 11/28/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cerliponase alfa, an enzyme replacement therapy for neuronal ceroid lipofuscinosis type 2 (CLN2), is currently available in England through a managed access agreement (MAA). It is administered every 2 weeks via an intracerebroventricular device. Here we report qualitative research with families of children with CLN2 disease and healthcare professionals (HCPs) who run the MAA, to understand how access to cerliponase alfa via the MAA at Great Ormond Street Hospital (GOSH) in London, and the overall management of CLN2 disease, was affected during the coronavirus disease 2019 (COVID-19) pandemic. METHODS Telephone interviews were conducted with nine families, representing 11 children with CLN2 disease, and two HCPs in November and December 2020. RESULTS Children had received cerliponase alfa treatment for a mean (SD) of 23.1 ± 24.7 months (7.1 ± 4.6 months in the MAA). Families travelled 7-398 km for treatment (mean 210 ± 111 km). Treatment with cerliponase alfa was designated "essential" by GOSH and continued as normal during the pandemic but with extra safety precautions, and no children missed any treatments. Families were highly motivated to continue treatment, despite considerable anxiety about the risk of coronavirus infection from travelling and staying overnight but were reassured by communications from GOSH and the safety precautions put in place. Support therapy services were widely compromised, causing families concern about deterioration in their children's condition. Families were confused about COVID-19 testing and shielding, and were unclear whether children with CLN2 disease were vulnerable to COVID-19. CONCLUSIONS Looking forward, advice for children with CLN2 disease should be specific and tailored, taking into account the family unit. Support therapies should be considered essential alongside cerliponase alfa treatment.
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Affiliation(s)
- Amanda Mortensen
- Batten Disease Family Association, Hamilton House, Mabledon Place, London, WC1H9BB, UK.
| | - Eva M Raebel
- Rare Disease Research Partners, MPS House, Amersham, HP7 9LP, UK
| | - Samantha Wiseman
- Rare Disease Research Partners, MPS House, Amersham, HP7 9LP, UK
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17
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McGinn RJ, Von Stein EL, Summers Stromberg JE, Li Y. Precision medicine in epilepsy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 190:147-188. [DOI: 10.1016/bs.pmbts.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Rodrigues D, de Castro MJ, Crujeiras P, Duat-Rodriguez A, Marco AV, Del Toro M, Couce ML, Colón C. The LINCE Project: A Pathway for Diagnosing NCL2 Disease. Front Pediatr 2022; 10:876688. [PMID: 35425725 PMCID: PMC9002010 DOI: 10.3389/fped.2022.876688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 03/07/2022] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION Neuronal Ceroid Lipofuscinosis (NCL) comprises a clinically and genetically heterogeneous group of 13 neurodegenerative lysosomal storage disorders. Neuronal Ceroid lipofuscinosis type 2 disease (NCL2), caused by the deficient lysosomal enzyme tripeptidyl peptidase 1 (TPP1), is the only one with an approved enzyme replacement treatment (ERT). Early initiation of ERT appears to modify significantly the natural history of the disease. We aimed to shorten the time to diagnosis of NCL2. METHODS In March 2017, we started per first time in Spain a selective screening program, the LINCE project, in pediatric patients with clinical symptoms compatible with NCL2 disease. The program covered the whole country. We distributed kits to pediatricians with the necessary material to assess patients. All samples in this study were received within one week of collection. Enzymatic activity determined on dried blood spots was the main method used to screen for TPP1 and palmitoyl protein thioesterase 1 (PPT1) for the differential diagnosis with neuronal ceroid lipofuscinosis type 1 (NCL1). RESULTS Over a period of three years, we received 71 samples. The analysis was minimally invasive, relatively cheap and fast-executing. Three cases identified as a direct result of the selective screening strategy were confirmed by genetic study of NCL2 disease with a median age of 4.5 years. Our screening method has a specificity of 100%, and, with the absence to date of false negatives. We did not detect any NCL1-positive cases. CONCLUSIONS LINCE proved to be a simple, useful, and reliable tool for the diagnosis of NCL2, enabling clinicians to diagnose NCL2 faster. The presence of NCL2-positive cases in our population and availability of treatment may facilitate the inclusion of NCL2 in neonatal screening programs for early diagnosis.
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Affiliation(s)
- Daniel Rodrigues
- Congenital Metabolic Diseases Unit, Department of Neonatology, University Clinical Hospital of Santiago de Compostela, Instituto de Investigación Sanitaria de Santiago (IDIS), European Reference Network for Hereditary Metabolic Disorders (MetabERN), Centro de Investigación Biomédica en Red Enfermedades Raras (CIBERER), Santiago de Compostela, Spain.,Department of Pediatrics, Faculty of Medicine, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Maria José de Castro
- Congenital Metabolic Diseases Unit, Department of Neonatology, University Clinical Hospital of Santiago de Compostela, Instituto de Investigación Sanitaria de Santiago (IDIS), European Reference Network for Hereditary Metabolic Disorders (MetabERN), Centro de Investigación Biomédica en Red Enfermedades Raras (CIBERER), Santiago de Compostela, Spain
| | - Pablo Crujeiras
- Congenital Metabolic Diseases Unit, Department of Neonatology, University Clinical Hospital of Santiago de Compostela, Instituto de Investigación Sanitaria de Santiago (IDIS), European Reference Network for Hereditary Metabolic Disorders (MetabERN), Centro de Investigación Biomédica en Red Enfermedades Raras (CIBERER), Santiago de Compostela, Spain.,Department of Pediatrics, Faculty of Medicine, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Anna Duat-Rodriguez
- Department of Neuropediatrics, Niño Jesús Children's Hospital, Madrid, Spain
| | - Ana Victoria Marco
- Genomics Unit, La Fe University and Polytechnic Hospital, Valencia, Spain
| | - Mireia Del Toro
- Pediatric Neurology Unit, Vall D'Hebron University Hospital, Barcelona, Spain
| | - María L Couce
- Congenital Metabolic Diseases Unit, Department of Neonatology, University Clinical Hospital of Santiago de Compostela, Instituto de Investigación Sanitaria de Santiago (IDIS), European Reference Network for Hereditary Metabolic Disorders (MetabERN), Centro de Investigación Biomédica en Red Enfermedades Raras (CIBERER), Santiago de Compostela, Spain.,Department of Pediatrics, Faculty of Medicine, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Cristóbal Colón
- Congenital Metabolic Diseases Unit, Department of Neonatology, University Clinical Hospital of Santiago de Compostela, Instituto de Investigación Sanitaria de Santiago (IDIS), European Reference Network for Hereditary Metabolic Disorders (MetabERN), Centro de Investigación Biomédica en Red Enfermedades Raras (CIBERER), Santiago de Compostela, Spain
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19
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Ługowska A, Purzycka-Olewiecka JK, Płoski R, Truszkowska G, Pronicki M, Felczak P, Śpiewak M, Podlecka-Piętowska A, Sitek M, Bilińska ZT, Leszek P, Bednarska-Makaruk M. Tripeptidyl Peptidase 1 (TPP1) Deficiency in a 36-Year-Old Patient with Cerebellar-Extrapyramidal Syndrome and Dilated Cardiomyopathy. Life (Basel) 2021; 12:life12010003. [PMID: 35054396 PMCID: PMC8779458 DOI: 10.3390/life12010003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 11/23/2022] Open
Abstract
We report on a 36-year-old man with cerebellar-extrapyramidal syndrome and severe heart failure because of dilated cardiomyopathy of unknown origin. Dysarthria and cardiac arrhythmia began at early childhood (4 years of age). Brain MRI (28 years of age) demonstrated severe cerebellar atrophy. At the age 32, he presented with dysarthria, ataxia, dystonia, and tremor of the right hand, bilateral slowed neural conduction in the visual pathways, and decreased mental acuity. At the age of 33 years, the patient underwent cardiac transplantation because of severe dilated cardiomyopathy. In the TPP1 gene, biallelic variants were identified: previously reported p.(Leu13Pro) and novel p.(Tyr508Cys) variant. Additionally, hemizygous novel missense variant in the ABCD1 gene was inherited from the mother p.(Arg17His). Normal very-long-chain fatty acids (VLCFA) levels both in patient and his mother excluded ABCD1 mutation as the pathogenic one. Tripeptidyl peptidase 1 (TPP1) activity was reduced (8,8 U/mg protein/h; reference range: 47.4 ± 10.7). In light microscopy the biopsy specimens obtained from explanted heart showed severe myocyte hypertrophy with perinuclear vacuolization with inclusions. Electron microscopy revealed absence of lipofuscin accumulation, no ultrastructural curvilinear profiles, fingerprint bodies, or granular osmiophilic deposits (GRODs) in lysosomes. As described here, the patient presents clinical symptoms observed in benign forms of ceroid lipofuscinosis type 2 (CLN2) and simultaneously some features of autosomal recessive spinocerebellar ataxia type 7 (SCAR7), which is also caused by mutations in the TPP1 gene.
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Affiliation(s)
- Agnieszka Ługowska
- Department of Genetics, Institute of Psychiatry and Neurology, Al. Sobieskiego 9, 02-957 Warsaw, Poland; (J.K.P.-O.); (M.B.-M.)
- Correspondence:
| | - Joanna K. Purzycka-Olewiecka
- Department of Genetics, Institute of Psychiatry and Neurology, Al. Sobieskiego 9, 02-957 Warsaw, Poland; (J.K.P.-O.); (M.B.-M.)
| | - Rafał Płoski
- Department of Medical Genetics, Medical University of Warsaw, ul. A. Pawińskiego 3c, 02-106 Warsaw, Poland;
| | - Grażyna Truszkowska
- Molecular Biology Laboratory, Department of Medical Biology, National Institute of Cardiology, ul. Alpejska 42, 04-628 Warsaw, Poland;
| | - Maciej Pronicki
- Department of Pathology, The Children’s Memorial Health Institute, al. Dzieci Polskich 20, 04-730 Warsaw, Poland;
| | - Paulina Felczak
- Department of Neuropathology, Institute of Psychiatry and Neurology, Al. Sobieskiego 9, 02-957 Warsaw, Poland;
| | - Mateusz Śpiewak
- Magnetic Resonance Unit, Department of Radiology, National Institute of Cardiology, ul. Alpejska 42, 04-628 Warsaw, Poland;
| | | | - Martyna Sitek
- Department of Neurology, Medical University of Warsaw, ul. Banacha 1a, 02-097 Warsaw, Poland; (A.P.-P.); (M.S.)
| | - Zofia T. Bilińska
- Unit for Screening Studies in Inherited Cardiovascular Diseases, National Institute of Cardiology, ul. Alpejska 42, 04-628 Warsaw, Poland;
| | - Przemysław Leszek
- Department of Heart Failure and Transplantology, National Institute of Cardiology, ul. Alpejska 42, 04-628 Warsaw, Poland;
| | - Małgorzata Bednarska-Makaruk
- Department of Genetics, Institute of Psychiatry and Neurology, Al. Sobieskiego 9, 02-957 Warsaw, Poland; (J.K.P.-O.); (M.B.-M.)
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20
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Holla VV, Jha S, Pal PK, Yadav R, Phulpagar P, Muthusamy B, Arunachal G. Spinocerebellar ataxia recessive type 7 due to novel compound heterozygous variants in TPP1: First report from India. Parkinsonism Relat Disord 2021; 94:117-119. [PMID: 34929425 DOI: 10.1016/j.parkreldis.2021.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/02/2021] [Accepted: 12/09/2021] [Indexed: 11/08/2022]
Affiliation(s)
- Vikram V Holla
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, 560029, India
| | - Shreyasi Jha
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, 560029, India
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, 560029, India
| | - Ravi Yadav
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, 560029, India.
| | - Prashant Phulpagar
- Institute of Bioinformatics, International Technology Park, Bengaluru, 560066, India; Manipal Academy of Higher Education, Manipal, 576104, India
| | - Babylakshmi Muthusamy
- Institute of Bioinformatics, International Technology Park, Bengaluru, 560066, India; Manipal Academy of Higher Education, Manipal, 576104, India
| | - Gautham Arunachal
- Department of Human Genetics, National Institute of Mental Health and Neurosciences, Bengaluru, 560029, India
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21
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Gardner E, Mole SE. The Genetic Basis of Phenotypic Heterogeneity in the Neuronal Ceroid Lipofuscinoses. Front Neurol 2021; 12:754045. [PMID: 34733232 PMCID: PMC8558747 DOI: 10.3389/fneur.2021.754045] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/20/2021] [Indexed: 12/12/2022] Open
Abstract
The neuronal ceroid lipofuscinoses (NCLs) are a group of inherited neurodegenerative disorders that affect children and adults. They share some similar clinical features and the accumulation of autofluorescent storage material. Since the discovery of the first causative genes, more than 530 mutations have been identified across 13 genes in cases diagnosed with NCL. These genes encode a variety of proteins whose functions have not been fully defined; most are lysosomal enzymes, or transmembrane proteins of the lysosome or other organelles. Many mutations in these genes are associated with a typical NCL disease phenotype. However, increasing numbers of variant disease phenotypes are being described, affecting age of onset, severity or progression, and including some distinct clinical phenotypes. This data is collated by the NCL Mutation Database which allows analysis from many perspectives. This article will summarise and interpret current knowledge and understanding of their genetic basis and phenotypic heterogeneity.
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Affiliation(s)
- Emily Gardner
- MRC Laboratory for Molecular Cell Biology and Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Sara E Mole
- MRC Laboratory for Molecular Cell Biology and Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
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22
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Towards Splicing Therapy for Lysosomal Storage Disorders: Methylxanthines and Luteolin Ameliorate Splicing Defects in Aspartylglucosaminuria and Classic Late Infantile Neuronal Ceroid Lipofuscinosis. Cells 2021; 10:cells10112813. [PMID: 34831035 PMCID: PMC8616534 DOI: 10.3390/cells10112813] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 10/01/2021] [Accepted: 10/15/2021] [Indexed: 12/22/2022] Open
Abstract
Splicing defects caused by mutations in the consensus sequences at the borders of introns and exons are common in human diseases. Such defects frequently result in a complete loss of function of the protein in question. Therapy approaches based on antisense oligonucleotides for specific gene mutations have been developed in the past, but they are very expensive and require invasive, life-long administration. Thus, modulation of splicing by means of small molecules is of great interest for the therapy of genetic diseases resulting from splice-site mutations. Using minigene approaches and patient cells, we here show that methylxanthine derivatives and the food-derived flavonoid luteolin are able to enhance the correct splicing of the AGA mRNA with a splice-site mutation c.128-2A>G in aspartylglucosaminuria, and result in increased AGA enzyme activity in patient cells. Furthermore, we also show that one of the most common disease causing TPP1 gene variants in classic late infantile neuronal ceroid lipofuscinosis may also be amenable to splicing modulation using similar substances. Therefore, our data suggest that splice-modulation with small molecules may be a valid therapy option for lysosomal storage disorders.
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23
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Thompson DA, Handley SE, Henderson RH, Marmoy OR, Gissen P. An ERG and OCT study of neuronal ceroid lipofuscinosis CLN2 Battens retinopathy. Eye (Lond) 2021; 35:2438-2448. [PMID: 34272513 PMCID: PMC8377094 DOI: 10.1038/s41433-021-01594-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 04/28/2021] [Accepted: 04/30/2021] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Late infantile neuronal ceroid lipofuscinosis (CLN2 Batten disease) is a rare, progressive neurodegenerative disease of childhood. The natural history of motor and language regression is used to monitor the efficacy of CNS treatments. Less is known about CLN2 retinopathy. Our aim is to elaborate the nature, age of onset, and symmetry of CLN2 retinopathy using visual electrophysiology and ophthalmic imaging. SUBJECTS AND METHODS We reviewed 22 patients with genetically confirmed CLN2 disease; seventeen showing classical and five atypical disease. Flash electroretinograms (ERGs), flash and pattern reversal visual evoked potentials (VEPs), recorded from awake children were collated. Available fundus images were graded, optical coherence tomography (OCT) central subfoveal thickness (CST) measured, and genotype, age, clinical vision assessment and motor language grades assembled. RESULTS ERGs show cone/rod system dysfunction preceded by localised macular ellipsoid zone disruption on OCT from 4.8 years. Electroencephalogram (EEG) time-locked spikes confounded both pattern 6/17 (35%) and flash VEPs 12/16 (75%). Paired right eye (RE) and left eye (LE) ERG amplitudes did not differ significantly for each flash stimulus at the p 0.001 level, Wilcoxon ranked signed test. Cone ERGs show a functional deficit before CST thinning in classical disease. Optomap hyper fundus autofluorescence (FAF) at the fovea was noted in three patients with normal ERGs. The oldest patient showed an ovoid aggregate above the external limiting membrane at the fovea, which did not affect the PERG. CONCLUSION ERG findings in CLN2 retinopathy show symmetrical cone-rod dysfunction, from 4y10m in this series, but a broad range of ages when ERG function is preserved.
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Affiliation(s)
- Dorothy A Thompson
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK.
- UCL Great Ormond Street Institute of Child Health, London, UK.
| | - Siân E Handley
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK
- UCL Great Ormond Street Institute of Child Health, London, UK
| | - Robert H Henderson
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK
- UCL Great Ormond Street Institute of Child Health, London, UK
| | - Oliver R Marmoy
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK
- UCL Great Ormond Street Institute of Child Health, London, UK
| | - Paul Gissen
- Genetics and Genomic Medicine, Great Ormond Street Institute of Child Health, University College London, London, UK
- NIHR Great Ormond Street Hospital Biomedical Research Centre, University College London, London, UK
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24
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Unraveling neuronal ceroid lipofuscinosis type 2 (CLN2) disease: A tertiary center experience for determinants of diagnostic delay. Eur J Paediatr Neurol 2021; 33:94-98. [PMID: 34119739 DOI: 10.1016/j.ejpn.2021.05.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/27/2021] [Accepted: 05/30/2021] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To evaluate the clinical phenotype, disease course, laboratory, and genetic features of patients with CLN2 disease over a 20 year period with a special emphasis on risk factors for diagnostic delay. METHODS Thirty patients (23 families) with CLN2 disease, evaluated between 1996 and 2019 in a tertiary referral center in Turkey, were included. Clinical features, diagnostic pathway, disease course, genetic data, electrophysiological, and neuroimaging findings were analyzed, retrospectively. The patients diagnosed between 1996 and 2009, and 2010-2019 were defined as group 1 (G1), and group 2 (G2), respectively. Patients in these two groups were also compared. RESULTS The median age at symptom-onset was 36 months (20 months-7 years). Most common presenting symptoms were seizures (70%), followed by language delay (43%), and psychomotor regression (27%). Median age at diagnosis was 5.2 years (1.6-11 years) with a median 27 months (1 month-7 years) of diagnostic delay. Age at diagnosis was earlier in G2 (4.6 years vs 7 years, p = 0.002), with a shorter time to diagnosis (21 months vs 39 months, p = 0.004). Median time between the onset of first symptoms and death was 8.3 years (SE 1.0). Electroencephalograms (EEG) revealed abnormal features predominantly in posterior hemispheral regions and a photoparoxysmal response to intermittent photic stimulation was detected in 53% of the patients. Cerebellar (96%)/cerebral atrophy (83%), and white matter changes (57%) were the most common radiological abnormalities. CONCLUSIONS Most of our patients presented with late-infantile onset seizures. Despite increased availability of enzymatic and molecular testing, there is still a considerable diagnostic delay.
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25
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Sondhi D, Kaminsky SM, Hackett NR, Pagovich OE, Rosenberg JB, De BP, Chen A, Van de Graaf B, Mezey JG, Mammen GW, Mancenido D, Xu F, Kosofsky B, Yohay K, Worgall S, Kaner RJ, Souwedaine M, Greenwald BM, Kaplitt M, Dyke JP, Ballon DJ, Heier LA, Kiss S, Crystal RG. Slowing late infantile Batten disease by direct brain parenchymal administration of a rh.10 adeno-associated virus expressing CLN2. Sci Transl Med 2021; 12:12/572/eabb5413. [PMID: 33268510 DOI: 10.1126/scitranslmed.abb5413] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 11/11/2020] [Indexed: 12/11/2022]
Abstract
Late infantile Batten disease (CLN2 disease) is an autosomal recessive, neurodegenerative lysosomal storage disease caused by mutations in the CLN2 gene encoding tripeptidyl peptidase 1 (TPP1). We tested intraparenchymal delivery of AAVrh.10hCLN2, a nonhuman serotype rh.10 adeno-associated virus vector encoding human CLN2, in a nonrandomized trial consisting of two arms assessed over 18 months: AAVrh.10hCLN2-treated cohort of 8 children with mild to moderate disease and an untreated, Weill Cornell natural history cohort consisting of 12 children. The treated cohort was also compared to an untreated European natural history cohort of CLN2 disease. The vector was administered through six burr holes directly to 12 sites in the brain without immunosuppression. In an additional safety assessment under a separate protocol, five children with severe CLN2 disease were treated with AAVrh.10hCLN2. The therapy was associated with a variety of expected adverse events, none causing long-term disability. Induction of systemic anti-AAVrh.10 immunity was mild. After therapy, the treated cohort had a 1.3- to 2.6-fold increase in cerebral spinal fluid TPP1. There was a slower loss of gray matter volume in four of seven children by MRI and a 42.4 and 47.5% reduction in the rate of decline of motor and language function, compared to Weill Cornell natural history cohort (P < 0.04) and European natural history cohort (P < 0.0001), respectively. Intraparenchymal brain administration of AAVrh.10hCLN2 slowed the progression of disease in children with CLN2 disease. However, improvements in vector design and delivery strategies will be necessary to halt disease progression using gene therapy.
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Affiliation(s)
- Dolan Sondhi
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Stephen M Kaminsky
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Neil R Hackett
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Odelya E Pagovich
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Jonathan B Rosenberg
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Bishnu P De
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Alvin Chen
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Benjamin Van de Graaf
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Jason G Mezey
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA.,Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853, USA
| | - Grace W Mammen
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Denesy Mancenido
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Fang Xu
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Barry Kosofsky
- Department of Pediatrics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Kaleb Yohay
- Department of Pediatrics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Stefan Worgall
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA.,Department of Pediatrics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Robert J Kaner
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA.,Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Mark Souwedaine
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
| | - Bruce M Greenwald
- Department of Pediatrics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Michael Kaplitt
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
| | - Jonathan P Dyke
- Department of Radiology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Douglas J Ballon
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA.,Department of Radiology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Linda A Heier
- Department of Radiology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Szilard Kiss
- Department of Ophthalmology, Retina Service, Weill Cornell Medical College, New York, NY 10065, USA
| | - Ronald G Crystal
- Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA. .,Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA
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Helman G, Taylor LE, Walkiewicz M, Le Moing M, Eggers S, Yaplito-Lee J, Fuller M, Dabscheck G, Rodriguez-Casero V, White SM, Simons C. Aberrant splicing and transcriptional activity of TPP1 result in CLN2-like disorder. Eur J Med Genet 2021; 64:104259. [PMID: 34126256 DOI: 10.1016/j.ejmg.2021.104259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/21/2021] [Accepted: 06/08/2021] [Indexed: 10/21/2022]
Abstract
RNA sequencing (RNAseq) is emerging as a complementary tool to DNA sequencing, providing utility in diagnosis for disorders such as neuronal ceroid lipofuscinosis CLN2 disease. We describe an individual with a presentation suggestive of an attenuated CLN2 phenotype, including a history of regression, recent-onset microcephaly and spasticity from age five years. Exome sequencing revealed two variants inherited in trans in TPP1, NM_000391.4:c.225A>G; p.(Gln75 = ) and NM_000391.4:c.1012C>G; p.(Gln338Glu), both classified as variants of uncertain significance. TPP1 activity was found to be significantly reduced in fibroblasts of the affected individual. RNAseq was performed to assess the impact of compound heterozygous variants in TPP1 and enabled the identification of three aberrant splicing events. The c.225A>G variant introduces a 5 nucleotide truncation of exon 3 and a loss of reading frame. The majority of CLN2 transcripts exclude either exon 8 or exons 7-8, resulting in large in-frame deletions. Isoform specific RT-PCR confirmed the aberrant splicing events are mutually exclusive, suggesting that the paternal exon 8 c.1012C>G variant results in exon skipping. This case study demonstrates how RNAseq can be used as an orthogonal test to inform the interpretation of some variants of unknown significance and its particular importance in disorders where effective disease management requires early diagnosis.
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Affiliation(s)
- Guy Helman
- Murdoch Children's Research Institute, The Royal Children's Hospital, Victoria, Australia; Institute for Molecular Bioscience, The University of Queensland, Queensland, Australia
| | - Lauren E Taylor
- Murdoch Children's Research Institute, The Royal Children's Hospital, Victoria, Australia; Department of Neurology, The Royal Children's Hospital, Victoria, Australia
| | - Marzena Walkiewicz
- Murdoch Children's Research Institute, The Royal Children's Hospital, Victoria, Australia
| | - Maelle Le Moing
- Victorian Clinical Genetics Services, The Royal Children's Hospital, Victoria, Australia
| | - Stefanie Eggers
- Victorian Clinical Genetics Services, The Royal Children's Hospital, Victoria, Australia
| | - Joy Yaplito-Lee
- Department of Metabolic Medicine, The Royal Children's Hospital, Melbourne, Parkville, Victoria, Australia; Department of Paediatrics, University of Melbourne, Victoria, Australia
| | - Maria Fuller
- Genetics and Molecular Pathology, SA Pathology [at Women's and Children's Hospital], North Adelaide, South Australia, Australia; Adelaide Medical School, University of Adelaide, South Australia, Australia
| | - Gabriel Dabscheck
- Murdoch Children's Research Institute, The Royal Children's Hospital, Victoria, Australia; Department of Neurology, The Royal Children's Hospital, Victoria, Australia
| | | | - Susan M White
- Victorian Clinical Genetics Services, The Royal Children's Hospital, Victoria, Australia; Department of Paediatrics, University of Melbourne, Victoria, Australia.
| | - Cas Simons
- Murdoch Children's Research Institute, The Royal Children's Hospital, Victoria, Australia; Institute for Molecular Bioscience, The University of Queensland, Queensland, Australia.
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Schaefers J, van der Giessen LJ, Klees C, Jacobs EH, Sieverdink S, Dremmen MHG, Spoor JKH, van der Ploeg AT, van den Hout JMP, Huidekoper HH. Presymptomatic treatment of classic late-infantile neuronal ceroid lipofuscinosis with cerliponase alfa. Orphanet J Rare Dis 2021; 16:221. [PMID: 33990214 PMCID: PMC8120778 DOI: 10.1186/s13023-021-01858-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 05/06/2021] [Indexed: 11/30/2022] Open
Abstract
Background Neuronal ceroid lipofuscinosis type 2 (CLN2 disease) is a rare rapidly progressive neurodegenerative disorder, resulting in early death. Intracerebroventricular enzyme replacement therapy (ERT) with cerliponase alfa is now available and has shown to delay disease progression in symptomatic patients. It is yet unknown if cerliponase alfa can prevent disease onset in presymptomatic patients. Results We evaluated the effect of 2 years of intracerebroventricular ERT in two siblings with CLN2 disease, one symptomatic (age 47 months) and one presymptomatic (age 23 months) at treatment start, using the CLN2 Clinical Rating Scale (CLN2 CRS), Gross Motor Function Measure-66 (GMFM-66) for motor function, Bayley Scales of Infant and Toddler Development, 3rd Edition, Dutch (BSID-III-NL) for neurocognitive development, brain MRI, and visual evoked potentials (VEP), electroretinogram (ERG) and retinoscopy for visual function. On the CLN2 CRS patient 1 showed a decline from 3 to 2 in the combined motor and language score due to regression in language use (CLN2 CRS total score after 2 years of treatment: 8), whereas a decline of 2 or more points in the combined motor and language score would be expected without treatment. Patient 2 retained the maximum score of 3 in all 4 subdomains (CLN2 CRS total score after 2 years of treatment: 12). The GMFM-66 total score declined from 46 to 39 in patient 1 and showed an age-appropriate increase from 66 to 84 in patient 2. Cognitive-developmental age decreased from 24 to 11 months in patient 1, whereas an increase in cognitive-developmental age from 21 to 39 months was seen in patient 2. Cerebral and cerebellar atrophy observed on MRI in patient 1 at age 42 months (before treatment) was not observed in patient 2 at age 48 months (after 2 years of treatment). Conclusion We show that cerliponase alfa is able to delay the onset of symptoms when treatment is started in a presymptomatic stage of CLN2 disease. Our results advocate the start of treatment at an early age before symptom onset, but should be confirmed in a larger cohort study.
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Affiliation(s)
- J Schaefers
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - L J van der Giessen
- Department of Pediatric Physiotherapy, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - C Klees
- Department of Child and Adolescent Psychiatry/Psychology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - E H Jacobs
- Department of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - S Sieverdink
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - M H G Dremmen
- Department of Radiology and Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - J K H Spoor
- Department of Pediatric Neurosurgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - A T van der Ploeg
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - J M P van den Hout
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - H H Huidekoper
- Department of Pediatrics, Center for Lysosomal and Metabolic Diseases, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
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28
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Wibbeler E, Wang R, Reyes EDL, Specchio N, Gissen P, Guelbert N, Nickel M, Schwering C, Lehwald L, Trivisano M, Lee L, Amato G, Cohen-Pfeffer J, Shediac R, Leal-Pardinas F, Schulz A. Cerliponase Alfa for the Treatment of Atypical Phenotypes of CLN2 Disease: A Retrospective Case Series. J Child Neurol 2021; 36:468-474. [PMID: 33356800 PMCID: PMC8027928 DOI: 10.1177/0883073820977997] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The classic phenotype of CLN2 disease (neuronal ceroid lipofuscinosis type 2) typically manifests between ages 2 and 4 years with a predictable clinical course marked by epilepsy, language developmental delay, and rapid psychomotor decline. Atypical phenotypes exhibit variable time of onset, symptomatology, and/or progression. Intracerebroventricular-administered cerliponase alfa (rhTPP1 enzyme) has been shown to stabilize motor and language function loss in patients with classic CLN2 disease, but its impact on individuals with atypical phenotypes has not been described. METHODS A chart review was conducted of 14 patients (8 male, 6 female) with atypical CLN2 phenotypes who received cerliponase alfa. Pre- and posttreatment CLN2 Clinical Rating Scale Motor and Language (ML) domain scores were compared. RESULTS Median age at first presenting symptom was 5.9 years. First reported symptoms were language abnormalities (6 [43%] patients), seizures (4 [29%]), ataxia/language abnormalities (3 [21%]), and ataxia alone (1 [7%]). Median age at diagnosis was 10.8 years. ML score declined before treatment in 13 (93%) patients. Median age at treatment initiation was 11.7 years; treatment duration ranged from 11 to 58 months. From treatment start, ML score remained stable in 11 patients (treatment duration 11-43 months), improved 1 point in 1 patient after 13 months, and declined 1 point in 2 patients after 15 and 58 months, respectively. There were 13 device-related infections in 8 patients (57%) and 10 hypersensitivity reactions in 6 (43%). CONCLUSIONS Cerliponase alfa is well tolerated and has the potential to stabilize motor and language function in patients with atypical phenotypes of CLN2 disease.
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Affiliation(s)
- Eva Wibbeler
- University Medical Center Hamburg-Eppendorf, Children’s Hospital, Hamburg, Germany
| | - Raymond Wang
- CHOC Children’s Specialists, Orange, CA, USA,University of California-Irvine School of Medicine, Irvine, CA, USA
| | - Emily de los Reyes
- Nationwide Children Hospital Columbus Ohio, Ohio State University, Columbus, OH, USA
| | | | - Paul Gissen
- The NIHR Great Ormond Street Hospital, Biomedical Research Centre, London, UK
| | - Norberto Guelbert
- Hospital de Niños de la Santísima Trinidad [Holy Trinity Children’s Hospital], Cordoba, Argentina
| | - Miriam Nickel
- University Medical Center Hamburg-Eppendorf, Children’s Hospital, Hamburg, Germany
| | - Christoph Schwering
- University Medical Center Hamburg-Eppendorf, Children’s Hospital, Hamburg, Germany
| | - Lenora Lehwald
- Nationwide Children Hospital Columbus Ohio, Ohio State University, Columbus, OH, USA
| | | | - Laura Lee
- The NIHR Great Ormond Street Hospital, Biomedical Research Centre, London, UK
| | | | | | | | | | - Angela Schulz
- University Medical Center Hamburg-Eppendorf, Children’s Hospital, Hamburg, Germany,Angela Schulz, MD, PhD, Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany.
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Mole SE, Schulz A, Badoe E, Berkovic SF, de Los Reyes EC, Dulz S, Gissen P, Guelbert N, Lourenco CM, Mason HL, Mink JW, Murphy N, Nickel M, Olaya JE, Scarpa M, Scheffer IE, Simonati A, Specchio N, Von Löbbecke I, Wang RY, Williams RE. Guidelines on the diagnosis, clinical assessments, treatment and management for CLN2 disease patients. Orphanet J Rare Dis 2021; 16:185. [PMID: 33882967 PMCID: PMC8059011 DOI: 10.1186/s13023-021-01813-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 04/06/2021] [Indexed: 11/28/2022] Open
Abstract
Background CLN2 disease (Neuronal Ceroid Lipofuscinosis Type 2) is an ultra-rare, neurodegenerative lysosomal storage disease, caused by an enzyme deficiency of tripeptidyl peptidase 1 (TPP1). Lack of disease awareness and the non-specificity of presenting symptoms often leads to delayed diagnosis. These guidelines provide robust evidence-based, expert-agreed recommendations on the risks/benefits of disease-modifying treatments and the medical interventions used to manage this condition. Methods An expert mapping tool process was developed ranking multidisciplinary professionals, with knowledge of CLN2 disease, diagnostic or management experience of CLN2 disease, or family support professionals. Individuals were sequentially approached to identify two chairs, ensuring that the process was transparent and unbiased. A systematic literature review of published evidence using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance was independently and simultaneously conducted to develop key statements based upon the strength of the publications. Clinical care statements formed the basis of an international modified Delphi consensus determination process using the virtual meeting (Within3) online platform which requested experts to agree or disagree with any changes. Statements reaching the consensus mark became the guiding statements within this manuscript, which were subsequently assessed against the Appraisal of Guidelines for Research and Evaluation (AGREEII) criteria. Results Twenty-one international experts from 7 different specialities, including a patient advocate, were identified. Fifty-three guideline statements were developed covering 13 domains: General Description and Statements, Diagnostics, Clinical Recommendations and Management, Assessments, Interventions and Treatment, Additional Care Considerations, Social Care Considerations, Pain Management, Epilepsy / Seizures, Nutritional Care Interventions, Respiratory Health, Sleep and Rest, and End of Life Care. Consensus was reached after a single round of voting, with one exception which was revised, and agreed by 100% of the SC and achieved 80% consensus in the second voting round. The overall AGREE II assessment score obtained for the development of the guidelines was 5.7 (where 1 represents the lowest quality, and 7 represents the highest quality). Conclusion This program provides robust evidence- and consensus-driven guidelines that can be used by all healthcare professionals involved in the management of patients with CLN2 disease and other neurodegenerative disorders. This addresses the clinical need to complement other information available. Supplementary Information The online version contains supplementary material available at 10.1186/s13023-021-01813-5.
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Affiliation(s)
| | - Angela Schulz
- Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Eben Badoe
- Korle Bu Teaching Hospital, University of Ghana Medical School, Accra, Ghana
| | - Samuel F Berkovic
- Austin Health Victoria, University of Melbourne, Heidelberg, VIC, Australia
| | | | - Simon Dulz
- Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Paul Gissen
- University College London, London, UK.,NIHR Great Ormond Street Hospital Biomedical Research Centre, London, UK
| | | | - Charles M Lourenco
- Universidade de São Paulo Faculdade de Medicina de Ribeirão Preto, Riberirao Preto, Brazil
| | | | - Jonathan W Mink
- Golisano Childrens' Hospital, University of Rochester Medical Center, Rochester, NY, USA
| | - Noreen Murphy
- Batten Disease Support and Research Association (BDSRA), Columbus, OH, USA
| | - Miriam Nickel
- Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Joffre E Olaya
- Children's Hospital of Orange County, Orange County, CA, USA
| | - Maurizio Scarpa
- Regional Coordinating Center for Rare Diseases, University Hospital Udine, Udine, Italy
| | - Ingrid E Scheffer
- Austin Health Victoria, University of Melbourne, Heidelberg, VIC, Australia.,Royal Children's Hospital, Florey and Murdoch Children's Research Institutes, Melbourne, Australia
| | - Alessandro Simonati
- Department of Surgery, Dentistry, Paediatrics and Gynaecology, University of Verona School of Medicine, Verona, Italy
| | | | | | - Raymond Y Wang
- Children's Hospital of Orange County, Orange County, CA, USA
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Ma L, Prada AM, Schmidt M, Morrow EM. Generation of pathogenic TPP1 mutations in human stem cells as a model for neuronal ceroid lipofuscinosis type 2 disease. Stem Cell Res 2021; 53:102323. [PMID: 33845243 PMCID: PMC9173593 DOI: 10.1016/j.scr.2021.102323] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 03/19/2021] [Accepted: 03/28/2021] [Indexed: 01/22/2023] Open
Abstract
Neuronal ceroid lipofuscinosis type 2 (CLN2 disease) is an autosomal recessive neurodegenerative disorder generally with onset at 2 to 4 years of age and characterized by seizures, loss of vision, progressive motor and mental decline, and premature death. CLN2 disease is caused by loss-of-function mutations in the tripeptidyl peptidase 1 (TPP1) gene leading to deficiency in TPP1 enzyme activity. Approximately 60% of patients have one of two pathogenic variants (c.509–1G > C or c.622C > T [p.(Arg208*)]). In order to generate a human stem cell model of CLN2 disease, we used CRISPR/Cas9-mediated knock-in technology to introduce these mutations in a homozygous state into H9 human embryonic stem cells. Heterozygous lines of the c.622C > T (p.(Arg208*)) mutation were also generated, which included a heterozygous mutant with a wild-type allele and different compound heterozygous coding mutants resulting from indels on one allele. We describe the methodology that led to the generation of the lines and provide data on the initial validation and characterization of these CLN2 disease models. Notably, both mutant lines (c.509–1G > C and c.622C > T [p.(Arg208*)]) in the homozygous state were shown to have reduced or absent protein, respectively, and deficiency of TPP1 enzyme activity. These models, which we have made available for wide-spread sharing, will be useful for future studies of molecular and cellular mechanisms underlying CLN2 disease and for therapeutic development.
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Affiliation(s)
- Li Ma
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA; Center for Translational Neuroscience, Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, Rhode Island 02912, USA
| | - Adriana M Prada
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA; Center for Translational Neuroscience, Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, Rhode Island 02912, USA
| | - Michael Schmidt
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA; Center for Translational Neuroscience, Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, Rhode Island 02912, USA; Hassenfeld Child Health Innovation Institute, Brown University, Providence, Rhode Island 02912, USA
| | - Eric M Morrow
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA; Center for Translational Neuroscience, Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, Rhode Island 02912, USA; Hassenfeld Child Health Innovation Institute, Brown University, Providence, Rhode Island 02912, USA.
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Lourenço CM, Pessoa A, Mendes CC, Rivera‐Nieto C, Vergara D, Troncoso M, Gardner E, Mallorens F, Tavera L, Lizcano LA, Atanacio N, Guelbert N, Specola N, Mancilla N, de Souza CFM, Mole SE. Revealing the clinical phenotype of atypical neuronal ceroid lipofuscinosis type 2 disease: Insights from the largest cohort in the world. J Paediatr Child Health 2021; 57:519-525. [PMID: 33377563 PMCID: PMC8049023 DOI: 10.1111/jpc.15250] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/20/2020] [Accepted: 10/04/2020] [Indexed: 01/04/2023]
Abstract
AIM Neuronal ceroid lipofuscinosis type 2 (CLN2) disease is an autosomal recessive inherited neurodegenerative lysosomal storage disorder caused by deficient tripeptidyl peptidase 1 (TPP1) enzyme, leading to progressive deterioration of neurological functions commonly occurring in children aged 2-4 years and culminating in early death. Atypical cases associated with earlier or later symptom onset, or even protracted course, have already been reported. Such variable manifestations may constitute an additional challenge to early diagnosis and initiation of appropriate treatment. The present work aimed to analyse clinical data from a cohort of Latin American CLN2 patients with atypical phenotypes. METHODS Experts in inborn errors of metabolism from Latin America selected patients from their centres who were deemed by the clinicians to have atypical forms of CLN2, according to the current literature on this topic and their practical experience. Clinical and genetic data from the medical records were retrospectively revised. All cases were presented and analysed by these experts at an Advisory Board Meeting in São Paulo, Brazil, in October 2018. RESULTS Seizures, language abnormalities and behavioural disorders were found as the first manifestations, appearing at the median age of 6 years, an older age than classically described for the late infantile form. Three novel mutations were also identified. CONCLUSION Our findings reinforce the inclusion of CLN2 in the differential diagnosis of children presenting with seizures, behavioural disorders and language abnormalities. Early diagnosis will allow early initiation of specific therapy.
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Affiliation(s)
- Charles M Lourenço
- School of MedicineEstácio University CenterRibeirão PretoSão PauloBrazil
| | - Andre Pessoa
- Pediatric Neurology Service, Albert Sabin Children's HospitalUniversity of Ceará StateFortalezaCearáBrazil
| | - Carmen C Mendes
- Reference Center in Inborn Errors of Metabolism, Department of PediatricsUniversidade Federal de São PauloSão PauloBrazil
| | | | - Diane Vergara
- Service of Children Neuropsychiatry, San Borja Arriarán HospitalSchool of Medicine of the University of ChileSantiagoChile
| | - Mónica Troncoso
- Service of Children Neuropsychiatry, San Borja Arriarán HospitalSchool of Medicine of the University of ChileSantiagoChile
| | - Emily Gardner
- UCL MRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUnited Kingdom
| | - Francisca Mallorens
- Medical Genetics SectionHospital Nacional Prof. A. PosadasBuenos AiresArgentina
| | | | | | - Nora Atanacio
- Dr. N.A Chamoles LaboratoryPedro de Elizalde Children's HospitalBuenos AiresArgentina
| | - Norberto Guelbert
- Metabolic Disease SectionCorboda Children's HospitalBuenos AiresArgentina
| | - Norma Specola
- Metabolic UnitChildren Hospital of La PlataBuenos AiresArgentina
| | - Nury Mancilla
- Department of PaediatricsNational University of ColombiaBogotáColombia
| | | | - Sara E Mole
- UCL MRC Laboratory for Molecular Cell Biology and UCL Great Ormond Street Institute of Child HealthUniversity College LondonLondonUnited Kingdom
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"Real world effectiveness of cerliponase alfa in classical and atypical patients. A case series". Mol Genet Metab Rep 2021; 27:100718. [PMID: 33604240 PMCID: PMC7873677 DOI: 10.1016/j.ymgmr.2021.100718] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/20/2021] [Accepted: 01/21/2021] [Indexed: 11/24/2022] Open
Abstract
Introduction Late infantile neuronal ceroid lipofuscinosis is an autosomal recessive disease caused by mutations in the CLN2/TPP1 gene, with secondary enzyme deficiency. In classical phenotypes, initial symptoms include seizures and delayed language development between 2 and 4 years of age. This article describes the presentation of CLN2 disease in a cohort of Colombian patients, as well as the impact of treatment on the course and progression of the disease. Methods Case series report of 8 patients with a confirmed diagnosis of neuronal ceroid lipofuscinosis treated with cerliponase alfa who remained on clinical and paraclinical follow-up for up to 24 months before and after treatment. Results An atypical phenotype, associated with initial symptoms and late diagnosis, was present in 5/8 patients. The most frequent symptoms were seizures and developmental delay, with age of onset at 24 months (classical phenotype) and 48 months (atypical phenotype). A novel mutation (c.1438G > A) was found in two siblings. All of the patients received cerliponase alfa, and there were no serious adverse events. No decline in the clinical status greater than 2 points on Hamburg, Weill Cornell and CNL2 clinical assessment scale was observed during follow-up after treatment initiation. Conclusion This is the first case series reported for neuronal ceroid lipofuscinosis patients in Colombia. In contrast with other reports, the majority of cases reported here displayed an atypical phenotype. Our study highlights the importance of early diagnosis and timely initiation of therapy, which is a feasible therapy, well tolerated by patients and accepted by caregivers in this country, generating a positive impact in the quality of life of CLN2 patients and on disease outcome.
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Cerliponase alfa changes the natural history of children with neuronal ceroid lipofuscinosis type 2: The first French cohort. Eur J Paediatr Neurol 2021; 30:17-21. [PMID: 33348105 DOI: 10.1016/j.ejpn.2020.12.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 11/30/2020] [Accepted: 12/04/2020] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Neuronal Ceroid Lipofuscinosis type 2 (CLN2) is a neurodegenerative lysosomal disease which leads to early dementia and death without treatment. The recently available therapy consists of intracerebroventricular enzyme substitution: cerliponase alfa. In this report, we describe the evolution of the first French children treated with cerliponase alfa. METHOD CLN2 Clinical Rating Scale Motor-Language (CLN2 ML) assesses the motor and language evolution of CLN2 patients. We retrospectively studied patients' medical records: clinical symptoms, MRI conclusions, gene mutation, side effects of infusions, patient's age and CLN2 ML scores at diagnosis, at the beginning of enzyme replacement therapy (ERT) and at the last evaluation. Seven patients were included. RESULTS Average age at diagnosis was 50 months ( ±10) with CLN2 ML score equal to 3.6 [1.5-5]. Average age at the beginning of ERT was 56 months ( ±13) with CLN2 ML score equal to 3.1 [1-5]. At the last available evaluation, average age was 82 months ( ±20) with CLN2 ML score equal to 2.8 [0-5]. Thus, in 26 months, the mean CLN2 ML score only decreased by 0.3 points. However, patients with a CLN2 ML score greater than three at the onset of ERT experienced a stabilisation or improvement of clinical signs, whereas patients with a CLN2 ML score less than three at baseline continue to deteriorate. CONCLUSION For patients starting ERT at an early stage of the disease, cerliponase alfa changes the natural history of the disease with a halt in disease progression or even a slight improvement in clinical symptoms.
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Amadori E, Scala M, Cereda GS, Vari MS, Marchese F, Di Pisa V, Mancardi MM, Giacomini T, Siri L, Vercellino F, Serino D, Orsini A, Bonuccelli A, Bagnasco I, Papa A, Minetti C, Cordelli DM, Striano P. Targeted re-sequencing for early diagnosis of genetic causes of childhood epilepsy: the Italian experience from the 'beyond epilepsy' project. Ital J Pediatr 2020; 46:92. [PMID: 32631363 PMCID: PMC7339579 DOI: 10.1186/s13052-020-00860-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/01/2020] [Indexed: 01/12/2023] Open
Abstract
Background Childhood epilepsies are a heterogeneous group of conditions differing in diagnostic criteria, management, and outcome. Late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2) is a neurodegenerative condition caused by biallelic TPP1 variants. This disorder presents with subtle and relatively non-specific symptoms, mimicking those observed in more common paediatric epilepsies and followed by rapid psychomotor deterioration and drug-resistant epilepsy. A prompt diagnosis is essential to adopt appropriate treatment and disease management strategies. Methods This is a prospective, multicentre study on the efficiency of targeted re-sequencing in the early identification of the genetic causes of childhood epilepsy, with particular regard to CLN2. After phenotypic characterization, a 283-gene Next Generation Sequencing panel was performed in 21 Italian children with neurodevelopmental abnormalities, aged between 24 and 60 months, experiencing first unprovoked seizure after 2 years of age. Results The average age at enrolment was 39.9 months, with a mean age at seizure onset of 30.9 months and a mean time interval between seizure onset and targeted resequencing of 9 months. Genetic confirmation was achieved in 4 out of 21 patients, with a diagnostic yield of 19%. In one case, the homozygous splice acceptor variant c.509-1G > C in TPP1 was identified, leading to a CLN2 diagnosis. Three pathogenic variants in MECP2 were also detected in three patients, including the frameshift variant c.1157_1186delinsA (p.Leu386Hisfs*9) in a girl with negative single gene sequencing. Variants of unknown significance (VUS) were found in 11 out of 21 (52.4%) individuals, whereas no clinically significant variants were observed in the remaining 6 subjects. Conclusions Our findings support the efficacy of target re-sequencing in the identification of the genetic causes of childhood epilepsy and suggest that this technique might prove successful in the early detection of CLN2 as well as other neurodevelopmental conditions.
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Affiliation(s)
- Elisabetta Amadori
- Pediatric Neurology and Muscular Diseases Unit, IRCCS 'G. Gaslini' Institute, 16147, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Marcello Scala
- Pediatric Neurology and Muscular Diseases Unit, IRCCS 'G. Gaslini' Institute, 16147, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Giulia Sofia Cereda
- Pediatric Neurology and Muscular Diseases Unit, IRCCS 'G. Gaslini' Institute, 16147, Genoa, Italy
| | - Maria Stella Vari
- Pediatric Neurology and Muscular Diseases Unit, IRCCS 'G. Gaslini' Institute, 16147, Genoa, Italy
| | - Francesca Marchese
- Pediatric Neurology and Muscular Diseases Unit, IRCCS 'G. Gaslini' Institute, 16147, Genoa, Italy
| | - Veronica Di Pisa
- Child Neurology and Psychiatry Unit, Department of Medical and Surgical Sciences (DIMEC), S. Orsola Hospital, University of Bologna, Bologna, Italy
| | - Maria Margherita Mancardi
- Child Neuropsychiatry Unit, Epilepsy Centre, Department of Clinical and Surgical Neurosciences and Rehabilitation, IRCSS 'G. Gaslini' Institute, Genoa, Italy
| | - Thea Giacomini
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.,Child Neuropsychiatry Unit, Epilepsy Centre, Department of Clinical and Surgical Neurosciences and Rehabilitation, IRCSS 'G. Gaslini' Institute, Genoa, Italy
| | - Laura Siri
- Child Neuropsychiatry Unit, IRCSS 'G. Gaslini' Institute, Genoa, Italy
| | - Fabiana Vercellino
- Department of Child Neurology and Psychiatry, Cesare Arrigo Hospital, Alessandria, Italy
| | - Domenico Serino
- Department of Paediatric Neurology, Royal Aberdeen Children's Hospital, Aberdeen, UK.,Child Neurology and Psychiatry Unit, ASL CN1, Cuneo, Italy
| | - Alessandro Orsini
- Pediatric Neurology, Pediatric Department, Azienda Ospedaliera Universitaria Pisana, University of Pisa, Pisa, Italy
| | - Alice Bonuccelli
- Pediatric Neurology, Pediatric Department, Azienda Ospedaliera Universitaria Pisana, University of Pisa, Pisa, Italy
| | - Irene Bagnasco
- Division of Child Neuropsychiatry, Martini Hospital, via Tofane 71, 10141, Torino, Italy
| | - Amanda Papa
- Department of Child Neuropsychiatry, AOU Maggiore della Carita, Novara, Italy
| | - Carlo Minetti
- Pediatric Neurology and Muscular Diseases Unit, IRCCS 'G. Gaslini' Institute, 16147, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Duccio Maria Cordelli
- Child Neurology and Psychiatry Unit, Department of Medical and Surgical Sciences (DIMEC), S. Orsola Hospital, University of Bologna, Bologna, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, IRCCS 'G. Gaslini' Institute, 16147, Genoa, Italy. .,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
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Diagnosis of late-infantile neuronal ceroid lipofuscinosis using dried blood spot-based assay for TPPI enzyme activity: TPPI diagnostic assay from DBS. Clin Chim Acta 2020; 507:62-68. [PMID: 32298681 DOI: 10.1016/j.cca.2020.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/08/2020] [Accepted: 04/09/2020] [Indexed: 11/24/2022]
Abstract
BACKGROUND The neuronal ceroid lipofuscinosis 2 (NCL2) or classic late-infantile neuronal ceroid lipofuscinosis (LINCL) is a neurogenetic disorder caused by mutations in the TPPI gene, which codes for the lysosomal tripeptidyl peptidase 1 (TPPI) EC 3.4.14.9. Loss of functional TPPI activity results in progressive visual and neurological symptoms starting at around 1-2 years of age causing early death. METHODS We report a DBS-based TPPI assay that cleaves a synthetic tetrapeptide substrate generating a product that is detected by HPLC. Probands and carriers were identified with 100% accuracy (7 probands, 30 carriers, 13 controls). RESULTS The assay detected a single TPPI activity at a lower pH towards the substrate tested. TPPI activity measurable when extracted at lower pH while inactive at neutral pH showed steady increase for at least 8 h incubation. No loss in TPPI activity was observed when DBS were stored for at least 2 weeks either in freezer, refrigerator, room temperature or 42 °C. CONCLUSION A sequence variant causing Arg339Gln substitution in a proband had 12% TPPI. TPPI activity can be reliably measured in DBS, giving an opportunity to diagnose NCL2 at birth and refer patients for enzyme replacement or other therapies for earliest intervention, or alternatively offers a second-tier confirmatory test.
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Specchio N, Pietrafusa N, Trivisano M. Changing Times for CLN2 Disease: The Era of Enzyme Replacement Therapy. Ther Clin Risk Manag 2020; 16:213-222. [PMID: 32280231 PMCID: PMC7127909 DOI: 10.2147/tcrm.s241048] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 03/18/2020] [Indexed: 01/23/2023] Open
Abstract
Neuronal ceroid lipofuscinosis type 2 (CLN2 disease) is a progressive neurodegenerative disease that results in early-onset, severe, progressive, neurological disabilities, leading to death in late childhood or early adolescence. Management has relied on symptomatic care, and supportive and palliative strategies, but the approval of the enzyme replacement therapy cerliponase alfa in the USA and Europe in 2017 brought different treatment opportunities. We describe the natural history of CLN2 disease, its diagnosis and management, and the preclinical and clinical development of cerliponase alfa. A PubMed search was undertaken for cerliponase alfa and rhTPP1 to identify preclinical and clinical studies. The hallmark-presenting symptoms of CLN2 disease are unprovoked seizures and a history of language delay, and progression involves motor dysfunction, and cognitive and visual decline. Cerliponase alfa has shown efficacy and tolerability in mouse and canine models of CLN2 disease when delivered intracerebroventricularly. Administration of cerliponase alfa in patients with CLN2 disease has led to significant reductions in the rate of decline of motor and language functions in comparison with a natural history population. The approval of cerliponase alfa has brought a new era for CLN2 disease, highlighting the need to understand different patterns of disease progression and clinical needs in treated patients.
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Affiliation(s)
- Nicola Specchio
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Nicola Pietrafusa
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Marina Trivisano
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
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Structural Features of Nucleoprotein CST/Shelterin Complex Involved in the Telomere Maintenance and Its Association with Disease Mutations. Cells 2020; 9:cells9020359. [PMID: 32033110 PMCID: PMC7072152 DOI: 10.3390/cells9020359] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 12/29/2022] Open
Abstract
Telomere comprises the ends of eukaryotic linear chromosomes and is composed of G-rich (TTAGGG) tandem repeats which play an important role in maintaining genome stability, premature aging and onsets of many diseases. Majority of the telomere are replicated by conventional DNA replication, and only the last bit of the lagging strand is synthesized by telomerase (a reverse transcriptase). In addition to replication, telomere maintenance is principally carried out by two key complexes known as shelterin (TRF1, TRF2, TIN2, RAP1, POT1, and TPP1) and CST (CDC13/CTC1, STN1, and TEN1). Shelterin protects the telomere from DNA damage response (DDR) and regulates telomere length by telomerase; while, CST govern the extension of telomere by telomerase and C strand fill-in synthesis. We have investigated both structural and biochemical features of shelterin and CST complexes to get a clear understanding of their importance in the telomere maintenance. Further, we have analyzed ~115 clinically important mutations in both of the complexes. Association of such mutations with specific cellular fault unveils the importance of shelterin and CST complexes in the maintenance of genome stability. A possibility of targeting shelterin and CST by small molecule inhibitors is further investigated towards the therapeutic management of associated diseases. Overall, this review provides a possible direction to understand the mechanisms of telomere borne diseases, and their therapeutic intervention.
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Nunes A, Meira J, Cunha C, Veiga M, Magalhães APSD, Málaga DR, Giugliani R, Leão EKE. A Case Report on the Challenging Diagnosis of Neuronal Ceroid Lipofuscinosis Type 2 (CLN2). JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2020. [DOI: 10.1590/2326-4594-jiems-2020-0010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
| | - Joanna Meira
- Universidade Federal da Bahia, Brazil; Universidade do Estado da Bahia, Brazil
| | | | | | | | | | - Roberto Giugliani
- Hospital de Clínicas de Porto Alegre, Brazil; Universidade Federal do Rio Grande do Sul, Brazil
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Gardner E, Bailey M, Schulz A, Aristorena M, Miller N, Mole SE. Mutation update: Review of TPP1 gene variants associated with neuronal ceroid lipofuscinosis CLN2 disease. Hum Mutat 2019; 40:1924-1938. [PMID: 31283065 PMCID: PMC6851559 DOI: 10.1002/humu.23860] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 01/03/2023]
Abstract
Neuronal ceroid lipofuscinosis type 2 (CLN2 disease) is an autosomal recessive condition caused by variants in the TPP1 gene, leading to deficient activity of the lysosomal enzyme tripeptidyl peptidase I (TPP1). We update on the spectrum of TPP1 variants associated with CLN2 disease, comprising 131 unique variants from 389 individuals (717 alleles) collected from the literature review, public databases, and laboratory communications. Previously unrecorded individuals were added to the UCL TPP1‐specific database. Two known pathogenic variants, c.509–1 G>C and c.622 C>T (p.(Arg208*)), collectively occur in 60% of affected individuals in the sample, and account for 50% of disease‐associated alleles. At least 86 variants (66%) are private to single families. Homozygosity occurs in 45% of individuals where both alleles are known (87% of reported individuals). Atypical CLN2 disease, TPP1 enzyme deficiency with disease onset and/or progression distinct from classic late‐infantile CLN2, represents 13% of individuals recorded with associated phenotype. NCBI ClinVar currently holds records for 37% of variants collected here. Effective CLN2 disease management requires early diagnosis; however, irreversible neurodegeneration occurs before a diagnosis is typically reached at age 5. Timely classification and public reporting of TPP1 variants is essential as molecular testing increases in use as a first‐line diagnostic test for pediatric‐onset neurological disease.
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Affiliation(s)
- Emily Gardner
- UCL MRC Laboratory for Molecular Cell Biology and UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Mitch Bailey
- Global Scientific Affairs, BioMarin Pharmaceutical Inc, Novato, California
| | - Angela Schulz
- Department of Paediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Mikel Aristorena
- UCL MRC Laboratory for Molecular Cell Biology and UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Nicole Miller
- Global Scientific Affairs, BioMarin Pharmaceutical Inc, Novato, California
| | - Sara E Mole
- UCL MRC Laboratory for Molecular Cell Biology and UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
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