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Mucopolysaccharidosis type IIIC (MPS IIIC) is a severe neurodegenerative lysosomal storage disease stemming from the loss of function of the lysosomal transmembrane protein Heparan glucosamine N-acetyltransferase (HGSNAT). This leads to the accumulation of the Glycosaminoglycan: Heparan Sulfate. Currently there are no available treatments for this disease. To address this, we developed a new mouse model which displays key disease features such as GAG buildup, Splenomegaly, neurological impairment, and the presence of disease specific non reducing end carbohydrates. In order to investigate a new therapeutic approach for this disease, we transplanted hematopoietic stem and progenitor cells (HSPCs) isolated from Wildtype mice into Hgsnat -/- mice and observed differences between the treated and untreated Hgsnat -/- mice. Transplanted HSPCs differentiated into macrophages in peripheral tissues and microglia-like cells in the brain. The exogenous supply of HSPCs resulted in partial restoration of HGSNAT expression and enzymatic activity which led to a notable reduction in MPS IIIC specific non reducing end carbohydrates within the Hgsnat -/- mice treated with WT HSPCs compared to the untreated Hgsnat -/-mice as well as Hgsnat -/-mice treated with HSPCs harvested from fellow Hgsnat -/-mice. Additionally, WT HSPC transplantation was able to improve neurological deficits, decrease splenomegaly and urine retention in the Hgsnat -/-mice. Histological analysis of the diseased mice kidneys revealed the presence of glomerular hyaline bodies with focal fibrosis and sclerosis which were mitigated in the mutant mice treated with WT HSPCs. The findings from this study provide evidence for the potential therapeutic benefits that WT HSPC transplantation offers MPS IIIC and could serve as an early step toward HSPC gene therapy becoming a clinical approach for rare hereditary diseases such as MPS IIIC.

Cipaglucosidase alfa plus miglustat (cipa + mig) is a novel, two-component therapy for Pompe disease. We report data from the Phase I/II ATB200-02 study for up to 48 months of treatment. Four adult cohorts, including one non-ambulatory ERT-experienced (n = 6) and three ambulatory cohorts, (two enzyme replacement therapy [ERT]-experienced cohorts [2-6 years (n = 11) and ≥ 7 years (n = 6)]), one ERT-naïve cohort (n = 6), received 20 mg/kg intravenous-infused cipa plus 260 mg oral mig biweekly. Change from baseline (CFBL) for multiple efficacy endpoints at 12, 24, 36, and 48 months, pharmacodynamics, pharmacokinetics, safety, and immunogenicity data were assessed. Six-minute walking distance (% predicted) improved at 12, 24, 36, and 48 months: pooled ambulatory ERT-experienced cohorts, mean(± standard deviation [SD]) CFBL: 6.1(± 7.84), n = 16; 5.4(± 10.56), n = 13; 3.4(± 14.66), n = 12; 5.9(± 17.36), n = 9, respectively; ERT-naïve cohort: 10.7(± 3.93), n = 6; 11.0(± 5.06), n = 6; 9.0(± 7.98), n = 5; 11.7(± 7.69), n = 4, respectively. Percent predicted forced vital capacity was generally stable in ERT-experienced cohorts, mean(± SD) CFBL - 1.2(± 5.95), n = 16; 1.0(± 7.96), n = 13; - 0.3(± 6.68), n = 10; 1.0(± 6.42), n = 6, respectively, and improved in the ERT-naïve cohort: 3.2(± 8.42), n = 6; 4.7(± 5.09), n = 6; 6.2(± 3.35), n = 5; 8.3(± 4.50), n = 4, respectively. Over 48 months, CK and Hex4 biomarkers improved in ambulatory cohorts. Overall, cipa + mig was well tolerated with a safety profile like alglucosidase alfa. ATB200-02 results show the potential benefits of cipa + mig as a long-term treatment option for Pompe disease. Trial registration number: NCT02675465 January 26, 2016.

BackgroundLysosomal storage diseases (LSDs) are inherited metabolic disorders that may lead to severe multi-organ disease. Current ERTs are limited by anti-drug antibodies, the blood-brain barrier, and early disease onset and progression before ERT is started. We have opened a phase I clinical trial of enzyme replacement therapy (ERT) for fetuses with LSDs (NCT04532047). We evaluated the attitudes of parents and patients with LSDs towards fetal clinical trials and therapies.MethodsA multidisciplinary team designed a survey which was distributed by five international patient advocacy groups. We collected patients' demographic, diagnostic, and treatment information. Associations between respondent characteristics and attitudes towards fetal therapies/trials were analyzed using multivariate ordinal logistic regression.ResultsThe survey was completed by 181 adults from 19 countries. The majority of respondents were mothers from the United States. The most common diseases were MPS1 (26%), MPS3 (19%), and infantile-onset Pompe (14%). Most patients (88%) were diagnosed after birth, at a median of 21 months. Altogether, 65% of participating patients and children of participants had received ERT, 27% a stem cell transplant, and 4% gene therapy. We found that half (49%) of respondents were unlikely to terminate a future affected pregnancy, 55% would enroll in a phase I clinical trial for fetal ERT, and 46% would enroll in a fetal gene therapy trial. Respondents who received postnatal ERT were significantly more likely enroll in a trial for fetal ERT or gene therapy (ERT OR 4.48, 95% CI 2.13-9.44, p < 0.0001; gene therapy OR 3.03, 95% CI 1.43-6.43, p = 0.0038). Respondents who used clinicaltrials.gov as a main source of information were more likely to choose to participate in a fetal trial (ERT OR 2.43, 95% CI 1.18-5.01, p = 0.016; gene therapy OR 2.86, 95% CI 1.27-6.46, p = 0.011).ConclusionsFamiliarity with postnatal ERT increased respondents' likelihood of pursuing

Sphingolipidoses such as Fabry disease, Gaucher disease, Krabbe disease, Niemann-Pick disease, Tay-Sachs disease, Sandhoff disease, metachromatic leukodystrophy and GM1 gangliosidosis are attributed to defective sphingolipid catabolism. This results in neurotoxicity and severe systemic manifestations. Because of the complexity of lysosphingolipid analysis, high-sensitivity techniques with excellent resolution are required to attain reliable analysis of urine samples of affected patients. Currently, there is no robust method using urine to simultaneously analyze a group of lysosphingolipids related to these rare diseases. A non-invasive approach was chosen for a simplified sample collection of biological matrices. The main objective of this research project is to develop/validate a method for the simultaneous analysis of several lysosphingolipids and their analogs in urine using tandem mass spectrometry (MS/MS). Secondary objectives: 1) Analysis of lysosphingolipids in urine samples from patients with the aforementioned diseases and age- and gender-matched controls to establish reference values; 2) Development and adaptation of the method using urine filter paper samples; 3) Technological transfer to the clinic. After sample preparation by solid phase extraction, the samples are analyzed by ultra-high-performance liquid chromatography in combination with MS/MS. Preliminary results are promising with a fast 15-minute multiplex method that analyzes 21 creatinine-normalized biomarkers for 8 diseases. The validation of the method includes measurements of intra- and interday test variations, linearity of the calibration curve, matrix effect, recovery, glass and plasticware adsorption, stability of metabolites at different temperatures, detection and quantification limits. The growing demand to quickly identify patients with different sphingolipidoses and offer time-effective monitoring and follow-up of their treatment is driving this project forward. In conclusi, Les sphingolipidoses telles que la maladie de Fabry, la maladie de Gaucher, la maladie de Krabbe, la maladie de Niemann-Pick, la maladie de Tay-Sachs, la maladie de Sandhoff, la leucodystrophie métachromatique et la gangliosidose GM1 sont attribuées à un catabolisme défectueux des sphingolipides. Il en résulte une neurotoxicité et des manifestations systémiques graves. En raison de la complexité de l'analyse des lysosphingolipides, des techniques de haute sensibilité avec une excellente résolution sont nécessaires pour obtenir une analyse fiable des échantillons d'urine des patients atteints. Actuellement, il n'existe pas de méthodes robustes utilisant l'urine pour analyser simultanément un groupe de lysosphingolipides liés à ces maladies rares. Une approche non-invasive a été choisie pour un prélèvement simplifié d'échantillons de matrices biologiques. L'objectif principal de ce projet de recherche est de développer/valider une méthode d'analyse simultanée de plusieurs lysosphingolipides et de leurs analogues dans l'urine par spectrométrie de masse en tandem (MS/MS). Objectifs secondaires : 1) Analyse des lysosphingolipides dans des échantillons d'urine provenant de patients atteints des maladies susmentionnées et de témoins appariés en fonction de l'âge et du sexe afin d'établir des valeurs de référence ; 2) Développement et adaptation de la méthode en utilisant des échantillons d'urine sur papier filtre ; 3) Transfert technologique vers la clinique. Après préparation des échantillons par extraction en phase solide, les échantillons sont analysés par chromatographie liquide à ultra-haute performance en combinaison avec MS/MS. Les résultats préliminaires sont prometteurs avec une méthode multiplex rapide de 15 minutes qui analyse 21 biomarqueurs normalisés à la créatinine pour 8 maladies. La validation de la méthode comprend les mesures de variations intra- et inter-journalières du test, la linéarité de la courbe d'étalonnage, l'effet de matrice, la récupération, l

GRN mutations cause frontotemporal dementia (GRN-FTD) due to deficiency in progranulin (PGRN), a lysosomal and secreted protein with unclear function. Here, we found that Grn-/- mice exhibit a global deficiency in bis(monoacylglycero)phosphate (BMP), an endolysosomal phospholipid we identified as a pH-dependent PGRN interactor as well as a redox-sensitive enhancer of lysosomal proteolysis and lipolysis. Grn-/- brains also showed an age-dependent, secondary storage of glucocerebrosidase substrate glucosylsphingosine. We investigated a protein replacement strategy by engineering protein transport vehicle (PTV):PGRN-a recombinant protein linking PGRN to a modified Fc domain that binds human transferrin receptor for enhanced CNS biodistribution. PTV:PGRN rescued various Grn-/- phenotypes in primary murine macrophages and human iPSC-derived microglia, including oxidative stress, lysosomal dysfunction, and endomembrane damage. Peripherally delivered PTV:PGRN corrected levels of BMP, glucosylsphingosine, and disease pathology in Grn-/- CNS, including microgliosis, lipofuscinosis, and neuronal damage. PTV:PGRN thus represents a potential biotherapeutic for GRN-FTD.

Over the past three decades the lysosomal storage diseases have served as model for rare disease treatment development. While these efforts have led to considerable success, important challenges remain. For example, no treatments are currently approved for nearly two thirds of all lysosomal diseases, and there is limited impact of the existing drugs on the central nervous system. In addition, the costs of these therapies are extremely high, in part due to the fact that drug development has focused on a “single hit” approach – i.e., one drug for one disease. To overcome these obstacles researchers have begun to focus on defining common disease mechanisms in the lysosomal diseases, particularly in the central nervous system, with the hope of identifying drugs that might be used in several lysosomal diseases rather than an individual disease. With this concept in mind, herein we review a new potential treatment approach for the lysosomal storage diseases that focuses on modulation of the endocannabinoid system. We provide a short introduction to lysosomal storage diseases and the endocannabinoid system, followed by a brief review of data supporting this concept.

Fabry disease is an X-linked lysosomal deposit disease that produces alpha A galactosidase deficiency. It is a difficult to diagnose disease due to the heterogeneity of its clinical manifestations, where classic manifestations such as angiokeratomas, cornea verticillata, proteinuria, chronic kidney disease that requires replacement therapy, left ventricular hypertrophy, arrhythmias and cerebrovascular disease predominate. Two phenotypes are mainly described, a classic one that is very rare, more severe and manifests itself at an early age, and a late phenotype which manifests itself at an older age and has heart, kidneys and nervous system as its main target organs. Its pathophysiology is complex, related to the accumulation of metabolites derived from glycosphingolipids, as well as the endothelial dysfunction and prothrombotic state that these generate at a systemic level. The diagnosis is made with evidence of decreased enzymatic function, after which a confirmatory genetic study is performed. Timely diagnosis is highly relevant, since there is an effective enzyme replacement therapy, which potentially modifies the natural history of the disease and increases patient survival., La enfermedad de Fabry es una enfermedad de depósito lisosomal ligada al cromosoma X que produce deficiencia de galactosidasa alfa A. Es una enfermedad difícil de diagnosticar debido a la heterogeneidad de sus manifestaciones clínicas, donde predominan manifestaciones clásicas como angioqueratomas, córnea verticillata, proteinuria, enfermedad renal crónica que requiere terapia sustitutiva, hipertrofia ventricular izquierda, arritmias y enfermedad cerebrovascular. Se describen principalmente dos fenotipos, uno clásico que es muy poco frecuente, más severo y se manifiesta a edades tempranas, y un fenotipo tardío que se manifiesta a mayor edad y tiene como principales órganos blanco corazón, riñones y sistema nervioso. Su fisiopatología es compleja, relacionada al acúmulo de metabolitos derivados de glucoesfingolípidos, así como la disfunción endotelial y estado protrombótico que estos generan a nivel sistémico. El diagnóstico se realiza al evidenciar una función enzimática disminuida, posterior a lo cual se realiza un estudio genético confirmatorio. Es de gran relevancia el diagnóstico oportuno, ya que existe terapia de sustitución enzimática eficaz, la cual potencialmente modifica la historia natural de la enfermedad e incrementa la sobrevida de los pacientes.

Although understudied relative to many phospholipids, accumulating evidence suggests that bis(monoacylglycero)phosphate (BMP) is an important class of regulatory lipid that plays key roles in lysosomal integrity and function. BMPs are rare in most mammalian tissues, comprising only a few percent of total cellular lipid content, but are elevated in cell types such as macrophages that rely heavily on lysosomal function. BMPs are markedly enriched in endosomal and lysosomal vesicles compared to other organelles and membranous structures, and their unique sn-1:sn-1' stereoconfiguration may confer stability within the hydrolytic lysosomal environment. BMP-enriched vesicles serve in endosomal-lysosomal trafficking and function as docking structures for the activation of lysosomal hydrolytic enzymes, notably those involved in the catabolic breakdown of sphingolipids. BMP levels are dysregulated in lysosomal storage disorders, phospholipidosis, metabolic diseases, liver and kidney diseases and neurodegenerative disorders. However, whether BMP alteration is a mediator or simply a marker of pathological states is unclear. Likewise, although BMP acyl chain composition may be altered with disease states, the functional significance of specific BMP species remains to be resolved. Newly developed tools for untargeted lipidomic analysis, together with a deeper understanding of enzymes mediating BMP synthesis and degradation, will help shed further light on the functional significance of BMPs in cellular physiology and pathology.

The cation-independent mannose 6-phosphate receptor (CI-MPR, IGF2 receptor or CD222), is a multifunctional glycoprotein required for normal development. Through the receptor's ability to bind unrelated extracellular and intracellular ligands, it participates in numerous functions including protein trafficking, lysosomal biogenesis, and regulation of cell growth. Clinically, endogenous CI-MPR delivers infused recombinant enzymes to lysosomes in the treatment of lysosomal storage diseases. Although four of the 15 domains comprising CI-MPR's extracellular region bind phosphorylated glycans on lysosomal enzymes, knowledge of how CI-MPR interacts with ~60 different lysosomal enzymes is limited. Here, we show by electron microscopy and hydroxyl radical protein footprinting that the N-terminal region of CI-MPR undergoes dynamic conformational changes as a consequence of ligand binding and different pH conditions. These data, coupled with X-ray crystallography, surface plasmon resonance and molecular modeling, allow us to propose a model explaining how high-affinity carbohydrate binding is achieved through allosteric domain cooperativity.

Cathepsins (CTSs) are ubiquitously expressed proteases normally found in the endolysosomal compartment where they mediate protein degradation and turnover. However, CTSs are also found in the cytoplasm, nucleus, and extracellular matrix where they actively participate in cell signaling, protein processing, and trafficking through the plasma and nuclear membranes and between intracellular organelles. Dysregulation in CTS expression and/or activity disrupts cellular homeostasis, thus contributing to many human diseases, including inflammatory and cardiovascular diseases, neurodegenerative disorders, diabetes, obesity, cancer, kidney dysfunction, and others. This review aimed to highlight the involvement of CTSs in inherited lysosomal storage disorders, with a primary focus to the emerging evidence on the role of CTSs in the pathophysiology of Mucopolysaccharidoses (MPSs). These latter diseases are characterized by severe neurological, skeletal and cardiovascular phenotypes, and no effective cure exists to date. The advance in the knowledge of the molecular mechanisms underlying the activity of CTSs in MPSs may open a new challenge for the development of novel therapeutic approaches for the cure of such intractable diseases.

Optimal lysosome function requires maintenance of an acidic pH maintained by proton pumps in combination with a counterion transporter such as the Cl-/H+ exchanger, CLCN7 (ClC-7), encoded by CLCN7. The role of ClC-7 in maintaining lysosomal pH has been controversial. In this paper, we performed clinical and genetic evaluations of two children of different ethnicities. Both children had delayed myelination and development, organomegaly, and hypopigmentation, but neither had osteopetrosis. Whole-exome and -genome sequencing revealed a de novo c.2144A>G variant in CLCN7 in both affected children. This p.Tyr715Cys variant, located in the C-terminal domain of ClC-7, resulted in increased outward currents when it was heterologously expressed in Xenopus oocytes. Fibroblasts from probands displayed a lysosomal pH approximately 0.2 units lower than that of control cells, and treatment with chloroquine normalized the pH. Primary fibroblasts from both probands also exhibited markedly enlarged intracellular vacuoles; this finding was recapitulated by the overexpression of human p.Tyr715Cys CLCN7 in control fibroblasts, reflecting the dominant, gain-of-function nature of the variant. A mouse harboring the knock-in Clcn7 variant exhibited hypopigmentation, hepatomegaly resulting from abnormal storage, and enlarged vacuoles in cultured fibroblasts. Our results show that p.Tyr715Cys is a gain-of-function CLCN7 variant associated with developmental delay, organomegaly, and hypopigmentation resulting from lysosomal hyperacidity, abnormal storage, and enlarged intracellular vacuoles. Our data supports the hypothesis that the ClC-7 antiporter plays a critical role in maintaining lysosomal pH.

What's already known? Prenatal diagnosis of lysosomal storage diseases is important to avoid high morbidity and mortality. What does this study add? Enzyme analysis may be alone used safely for the prenatal diagnosis of lysosomal storage disases. In populations with a high rate of consanguinity such as ours, prenatal diagnosis of lysosomal storage diseases is also more important due to increased rates of the disease, and enzyme analysis may be chosen for the prenatal diagnosis.

What's already known? Prenatal diagnosis of lysosomal storage diseases is important to avoid high morbidity and mortality. What does this study add? Enzyme analysis may be alone used safely for the prenatal diagnosis of lysosomal storage disases. In populations with a high rate of consanguinity such as ours, prenatal diagnosis of lysosomal storage diseases is also more important due to increased rates of the disease, and enzyme analysis may be chosen for the prenatal diagnosis.

Актуальність. На сьогодні виявлені кілька тисяч спадкових захворювань, що характеризуються ураженням нервової системи. До них належать лізосомні хвороби накопичення. Група цих захворювань включає майже 60 різних нозологічних форм спадкових моногенних порушень обміну речовин. Клінічна картина лізосомних хвороб характеризується прогредієнтним перебігом, мультисистемними порушеннями (ураження кісток скелета, м’язів, серцево-судинної, дихальної систем тощо). За тяжкого перебігу цих захворювань відзначають ураження нервової системи. Нейродегенеративні захворювання у дітей зазвичай спричинені лізосомними хворобами накопичення (ЛХН). Діагностика лізосомних хвороб в Україні розпочата у 1995 р. в НДСЛ «Охматдит». Уперше в Україні проаналізовані всі випадки лізосомних хвороб накопичення, діагностовані в період 1995–2016 рр., а також їх поширеність в українській популяції. Останніми роками спектр лабораторної діагностики ЛХН суттєво розширився, накопичено унікальний досвід клінічної ідентифікації різних форм цих рідкісних захворювань, що позначається на частоті їх виявлення, дає можливість аналізувати епідеміологічні показники, розробляти ефективні заходи щодо оптимізації ранньої діагностики. Мета. Вивчення поширеності та спектра нейропатичних форм лізосомних хвороб накопичення в Україні, порівняння отриманих результатів з даними епідеміологічних досліджень, проведених в інших країнах. Матеріали та методи. Проаналізовано клінічні та лабораторні дані пацієнтів, у яких діагностовано різні форми лізосомних хвороб, у тому числі і нейропатичні, за період спостереження 1995–2016 рр. НДСЛ «Охматдит» — єдиний лікувальний заклад в Україні, де здійснюється клініко-лабораторна діагностика цих захворювань. Поширеність лізосомних хвороб розраховували як відношення загальної кількості пацієнтів із діагнозом певної ЛХН до загальної кількості дітей, народжених живими у той самий період часу, що і хворі, в яких у подальшому діагностовано лізосомні хвороби (з розрахунку на 100 000 осіб, які нар, Актуальность. На сегодняшний день обнаружено несколько тысяч наследственных заболеваний, характеризующихся поражением нервной системы. К ним относят лизосомные болезни накопления (ЛБН). Группа этих заболеваний включает почти 60 различных нозологических форм наследственных моногенных нарушений обмена веществ. Клиническая картина лизосомных болезней характеризуется прогредиентным течением, мультисистемными нарушениями (поражение костей скелета, мышц, сердечно-сосудистой, дыхательной систем и т.д.). При тяжелом течении этих заболеваний отмечают поражение нервной системы. Лизосомные болезни накопления являются наиболее частой причиной нейродегенеративных заболеваний у детей. Диагностика лизосомных болезней в Украине начата в 1995 году в НГСБ «Охматдет». Впервые в Украине проанализированы все диагностированные случаи лизосомных болезней накопления, которые были выявлены в период 1995–2016 гг., а также распространенность этих заболеваний в украинской популяции. В последние годы спектр лабораторной диагностики ЛБН существенно расширился, накоплен уникальный опыт клинической идентификации различных форм этих редких заболеваний, что сказывается на частоте их диагностики, позволяет анализировать эпидемиологические показатели и разработать эффективные меры по оптимизации ранней диагностики. Цель. Изучение распространенности и спектра нейропатических форм лизосомных болезней накопления в Украине, сравнение результатов с данными эпидемиологических исследований, проведенных в других странах. Материалы и методы. Проведен анализ клинических и лабораторных данных пациентов, у которых диагностированы различные формы лизосомных болезней, в том числе и нейропатические, за период наблюдения 1995–2016 гг. НГСБ «Охматдет» — единственное лечебное учреждение в Украине, в котором проводится клинико-лабораторная диагностика этих заболеваний. Распространенность лизосомных заболеваний рассчитывали как соотношение общего количества пациентов с определенным диагнозом лизосомной болезни с общим ко, Background. To date, several thousands of hereditary diseases have been detected, characterized by the defeat of the nervous system. These include lysosomal storage diseases (LSD). Lysosomal storage desiaeses — is a large group of monogenic metabolic disorders (about 60), inherited mainly by the autosomal recessive type; most of them — are serious diseases with progressive flow that cause severe disability and early death of the patients. LSD are characterized by accumulation of enzymes substrates or products of their incomplete degradation and segregated cytoplasmic components, etc. in different cells and tissues and it causes many disorders. Depending on the accumulated substrate nature, the following LSD are distinguished: mucopolysaccharidosis, sphingolipidosis, mucolipidosis, oligosaccharidosis, etc. Certain LSD clinical flow depends on the pathological process type and location, accumulated biochemical substrate nature, and is usually multisymptomatic. Within one nosological form various phenotypes are found: from «soft» to severe; first symptoms of the disease may be nonspecific, reminiscent of other, more common diseases. Most LSD require complex stage-by-stage clinical and laboratory diagnostics. Until recently almost all LSD considered as incurable; specific correction methods were successfully developed and introduced into medical — it has become one of the most significant achievements in a worldwide medical science of recent decades. Recently, significantly expanded range of LSD laboratory diagnostics gained unique experience in clinical identification of their various forms that significantly influenced on the disease incidence revealing, allowed to analyze epidemiological indicators, to develop effective measures for early diagnosis optimization. The purpose of the study was to study the prevalence and spectrum of neuropathic forms of lysosomal accumulation diseases in Ukraine, comparing the results with epidemiological studies conducted in other coun

Introduction: Cholesteryl Ester Storage Disease (CESD) is a lysosomal storage disorder, its presentation is highly variable and its diagnosis challenging. In addition, there are several abnormalities observed in patients with CESD who overlap with more common diagnoses and are likely to be underdiagnosed. Most patients reported to date are carriers of the E8SJM mutation in the LIPA gene. In this sense, diagnostic assistance is essential because there are options for therapy in development, as well as mutation prevalence studies. Design: Observational research. Objective: To standardize the real-time PCR technique for the detection of the most frequent mutation, E8SJM, in peripheral blood and liver biopsy specimens for the diagnosis of CESD and future mutation prevalence studies. Institution: Center of Gene Therapy of the Hospital de Clinicas de Porto Alegre (HCPA), Brazil. Biological material: DNA samples extracted from peripheral blood and paraffinembedded liver tissue. Main outcome measures: Presence / Absence of E8SJM mutation. Results: The PCR reaction was standardized in real time; the mutation was correctly detected and validated by Sanger sequencing. The mutation was analyzed in 137 samples and found in only one patient who entered the Medical Genetics Service of the HCPA with clinical and biochemical diagnosis of CESD/Wolman. Conclusions: The real-time PCR technique is ideal for rapid and large-scale detection of the frequent CESD-associated mutation., Introducción: La enfermedad por Almacenamiento de Ésteres de Colesterol (CESD; Cholesteryl Ester Storage Disease) es una enfermedad de depósito lisosomal, su presentación es bastante variable y su diagnóstico constituye un desafío. Además, existe un número de anomalías observadas en los pacientes con CESD que se sobreponen a diagnósticos más comunes, siendo probable que sea subdiagnosticada. La mayoría de pacientes relatados hasta el momento son portadores de la mutación E8SJM en el gen LIPA. En este sentido, el auxilio en el diagnóstico es fundamental pues existen opciones de terapia en desarrollo. Diseño: Estudio observacional. Objetivo: Estandarizar la técnica de PCR en tiempo real para la detección de la mutación más frecuente, E8SJM, en muestras de sangre periférica y de biopsia hepática para el auxilio diagnóstico de CESD y futuros estudios de prevalencia de la mutación. Institución: Centro de Terapia Génica del Hospital de Clínicas de Porto Alegre (HCPA), Brasil. Material biológico: Muestras de ADN extraídas de sangre periférica y tejido hepático parafinado. Principales medidas de resultados: Presencia/Ausencia de la mutación E8SJM. Resultados: Se estandarizó la reacción de PCR en tiempo real, la mutación fue detectada correctamente y posteriormente validada por secuenciación de Sanger. La mutación fue analizada en 137 muestras y encontrada en apenas una paciente que ingresó al Servicio de Genética Médica del HCPA con diagnóstico clínico y bioquímico de CESD/Wolman. Conclusiones: La técnica de PCR en tiempo real es ideal para la detección rápida y en gran escala de la mutación frecuente asociada a CESD.

Nrf2 (nuclear factor [erythroid-derived 2]-like 2; the transcriptional master regulator of the antioxidant stress response) is regulated through interaction with its cytoplasmic inhibitor Keap1 (Kelch-like ECH-associated protein 1), which under basal conditions targets Nrf2 for proteasomal degradation. Sequestosome 1 (SQSTM1)/p62-a multifunctional adapter protein that accumulates following autophagy inhibition and can serve as a diagnostic marker for human autophagic vacuolar myopathies (AVMs)-was recently shown to compete with Nrf2 for Keap1 binding, resulting in activation of the Nrf2 pathway. In this study, we used 55 human muscle biopsies divided into five groups [normal control, hydroxychloroquine- or colchicine-treated non-AVM control, hydroxychloroquine- or colchicine-induced toxic AVM, polymyositis, and inclusion body myositis (IBM)] to evaluate whether Keap1-SQSTM1 interaction led to increased Nrf2 signaling in human AVMs. In toxic AVMs and IBM, but not in control muscle groups or polymyositis, Keap1 antibody labeled sarcoplasmic protein aggregates that can be used as an alternate diagnostic marker for both AVM types; these Keap1-positive aggregates were co-labeled with the antibody against SQSTM1 but not with the antibody against autophagosome marker LC3 (microtubule-associated protein 1 light chain 3). In human AVM muscle, sequestration of Keap1 into the SQSTM1-positive protein aggregates was accompanied by an increase in mRNA and protein levels of Nrf2 target genes; similarly, treatment of differentiated C2C12 myotubes with autophagy inhibitor chloroquine led to an increase in the nuclear Nrf2 protein level and an increase in expression of the Nrf2-regulated genes. Taken together, our findings demonstrate that Nrf2 signaling is upregulated in autophagic muscle disorders and raise the possibility that autophagy disruption in skeletal muscle leads to dysregulation of cellular redox homeostasis.

The US Food and Drug Administration (FDA) and National Organization for Rare Disease (NORD) convened a public workshop titled "Immune Responses to Enzyme Replacement Therapies: Role of Immune Tolerance Induction" to discuss the impact of anti-drug antibodies (ADAs) on efficacy and safety of enzyme replacement therapies (ERTs) intended to treat patients with lysosomal storage diseases (LSDs). Participants in the workshop included FDA staff, clinicians, scientists, patients, industry, and advocacy group representatives. The risks and benefits of implementing prophylactic immune tolerance induction (ITI) to reduce the potential clinical impact of antibody development were considered. Complications due to immune responses to ERT are being recognized with increasing experience and lengths of exposure to ERTs to treat several LSDs. Strategies to mitigate immune responses and to optimize therapies are needed. Discussions during the workshop resulted in the identification of knowledge gaps and future areas of research, as well as the following proposals from the participants: (1) systematic collection of longitudinal data on immunogenicity to better understand the impact of ADAs on long-term clinical outcomes; (2) development of disease-specific biomarkers and outcome measures to assess the effect of ADAs and ITI on efficacy and safety; (3) development of consistent approaches to ADA assays to allow comparisons of immunogenicity data across different products and disease groups, and to expedite reporting of results; (4) establishment of a system to widely share data on antibody titers following treatment with ERTs; (5) identification of components of the protein that are immunogenic so that triggers and components of the immune responses can be targeted in ITI; and (6) consideration of early ITI in patients who are at risk of developing clinically relevant ADA that have been demonstrated to worsen treatment outcomes.

The US Food and Drug Administration (FDA) and National Organization for Rare Disease (NORD) convened a public workshop titled "Immune Responses to Enzyme Replacement Therapies: Role of Immune Tolerance Induction" to discuss the impact of anti-drug antibodies (ADAs) on efficacy and safety of enzyme replacement therapies (ERTs) intended to treat patients with lysosomal storage diseases (LSDs). Participants in the workshop included FDA staff, clinicians, scientists, patients, industry, and advocacy group representatives. The risks and benefits of implementing prophylactic immune tolerance induction (ITI) to reduce the potential clinical impact of antibody development were considered. Complications due to immune responses to ERT are being recognized with increasing experience and lengths of exposure to ERTs to treat several LSDs. Strategies to mitigate immune responses and to optimize therapies are needed. Discussions during the workshop resulted in the identification of knowledge gaps and future areas of research, as well as the following proposals from the participants: (1) systematic collection of longitudinal data on immunogenicity to better understand the impact of ADAs on long-term clinical outcomes; (2) development of disease-specific biomarkers and outcome measures to assess the effect of ADAs and ITI on efficacy and safety; (3) development of consistent approaches to ADA assays to allow comparisons of immunogenicity data across different products and disease groups, and to expedite reporting of results; (4) establishment of a system to widely share data on antibody titers following treatment with ERTs; (5) identification of components of the protein that are immunogenic so that triggers and components of the immune responses can be targeted in ITI; and (6) consideration of early ITI in patients who are at risk of developing clinically relevant ADA that have been demonstrated to worsen treatment outcomes.

Morquio’s disease (MPS IV-A) is produced by two different enzymatic defects. Since enzy-matic replacement therapy (ERT) is available for some LDD and others under development, this group of diseases have created great inter-est within the scientific community due to the fact that promising therapeutic alternative will be available to change disese course of affected patient. We present a case with albuminuria, La Enfermedad de Morquio (MPS IV-A) es producida por dos defectos enzimáticos diferentes. Desde que la terapia de sustitución enzimática (TSE) se encuentra disponible para algunas EDL y en desarrollo para otras, este grupo de patologías han despertado un gran interés en la comunidad científica debido a que la misma parecería una alternativa terapéutica prometedora para cambiar el curso evolutivo de los pacientes afectados. Se presenta un caso con presencia de albuminuria.

Pediatric-onset ataxias often present clinically as developmental delay and intellectual disability, with prominent cerebellar atrophy as a key neuroradiographic finding. Here we describe a new clinically distinguishable recessive syndrome in 12 families with cerebellar atrophy together with ataxia, coarsened facial features and intellectual disability, due to truncating mutations in the sorting nexin gene SNX14, encoding a ubiquitously expressed modular PX domain-containing sorting factor. We found SNX14 localized to lysosomes and associated with phosphatidylinositol (3,5)-bisphosphate, a key component of late endosomes/lysosomes. Patient-derived cells showed engorged lysosomes and a slower autophagosome clearance rate upon autophagy induction by starvation. Zebrafish morphants for snx14 showed dramatic loss of cerebellar parenchyma, accumulation of autophagosomes and activation of apoptosis. Our results characterize a unique ataxia syndrome due to biallelic SNX14 mutations leading to lysosome-autophagosome dysfunction.

Pediatric-onset ataxias often present clinically as developmental delay and intellectual disability, with prominent cerebellar atrophy as a key neuroradiographic finding. Here we describe a new clinically distinguishable recessive syndrome in 12 families with cerebellar atrophy together with ataxia, coarsened facial features and intellectual disability, due to truncating mutations in the sorting nexin gene SNX14, encoding a ubiquitously expressed modular PX domain-containing sorting factor. We found SNX14 localized to lysosomes and associated with phosphatidylinositol (3,5)-bisphosphate, a key component of late endosomes/lysosomes. Patient-derived cells showed engorged lysosomes and a slower autophagosome clearance rate upon autophagy induction by starvation. Zebrafish morphants for snx14 showed dramatic loss of cerebellar parenchyma, accumulation of autophagosomes and activation of apoptosis. Our results characterize a unique ataxia syndrome due to biallelic SNX14 mutations leading to lysosome-autophagosome dysfunction.

Lysosomal storage diseases (LSDs) are a group of more than 40 genetically inherited diseases that result from dysfunction of specific proteins, often an enzyme, located in lysosomes within cells which leads to abnormal lysosomal accumulation of specific macromolecules. As a result, cell malfunction occurs and escalates into multi-tissue and multi-organ failures, often resulting in premature death. For several early onset LSDs, the central nervous system (CNS) is also affected and manifests fatal neuropathic and/or neurodegenerative symptoms. Within the last two decades, treatment for selective LSDs has become clinically available. Specifically, enzyme replacement therapy (ERT) by intravenous injection of recombinant enzymes holds relevant promise. Yet current ERT results in suboptimal enzyme biodistribution to many target organs, including the peripheral organs and also the CNS. Delivery to the CNS is particularly impeded due to the tight blood-brain barrier (BBB) that strictly regulates passage between the circulation system and the brain tissue. We explored the use of targeted drug delivery systems to address this issue. Specifically, we focused on targeting intercellular adhesion molecule-1 (ICAM-1), a cell surface glycoprotein that is upregulated under pathological conditions, including LSDs. In this dissertation, using in vitro, cell culture, and in vivo techniques, we examined whether ICAM-1-targeted polymer nanocarriers: (1) enhance binding, uptake, and lysosomal delivery of different enzymes in cells, (2) provide targeting and transport across endothelial and subendthelial cells of the BBB, and (3) improve accumulation of lysosomal enzymes to peripheral organs and the brain. Results suggest that after intravenous injection of enzyme coupled to ICAM-1-targeted nanocarriers, ICAM-1 targeting shift these enzymes from the circulation to tissues, enhancing enzyme accumulation over non-targeted counterparts both in peripheral organs and the brain. This could be mo

Recombinant adeno-associated virus (rAAV) vectors mediating long term transgene expression are excellent gene therapy tools for chronic neurological diseases. While rAAV2 was the first serotype tested in the clinics, more efficient vectors derived from the rh10 serotype are currently being evaluated and other serotypes are likely to be tested in the near future. In addition, aside from the currently used stereotaxy-guided intraparenchymal delivery, new techniques for global brain transduction (by intravenous or intra-cerebrospinal injections) are very promising. Various strategies for therapeutic gene delivery to the central nervous system have been explored in human clinical trials in the past decade. Canavan disease, a genetic disease caused by an enzymatic deficiency, was the first to be approved. Three gene transfer paradigms for Parkinson's disease have been explored: converting L-dopa into dopamine through AADC gene delivery in the putamen; synthesizing GABA through GAD gene delivery in the overactive subthalamic nucleus and providing neurotrophic support through neurturin gene delivery in the nigro-striatal pathway. These pioneer clinical trials demonstrated the safety and tolerability of rAAV delivery in the human brain at moderate doses. Therapeutic effects however, were modest, emphasizing the need for higher doses of the therapeutic transgene product which could be achieved using more efficient vectors or expression cassettes. This will require re-addressing pharmacological aspects, with attention to which cases require either localized and cell-type specific expression or efficient brain-wide transgene expression, and when it is necessary to modulate or terminate the administration of transgene product. The ongoing development of targeted and regulated rAAV vectors is described. © 2013 The British Pharmacological Society., SCOPUS: ar.j, FLWIN, info:eu-repo/semantics/published

Recombinant adeno-associated virus (rAAV) vectors mediating long term transgene expression are excellent gene therapy tools for chronic neurological diseases. While rAAV2 was the first serotype tested in the clinics, more efficient vectors derived from the rh10 serotype are currently being evaluated and other serotypes are likely to be tested in the near future. In addition, aside from the currently used stereotaxy-guided intraparenchymal delivery, new techniques for global brain transduction (by intravenous or intra-cerebrospinal injections) are very promising. Various strategies for therapeutic gene delivery to the central nervous system have been explored in human clinical trials in the past decade. Canavan disease, a genetic disease caused by an enzymatic deficiency, was the first to be approved. Three gene transfer paradigms for Parkinson's disease have been explored: converting L-dopa into dopamine through AADC gene delivery in the putamen; synthesizing GABA through GAD gene delivery in the overactive subthalamic nucleus and providing neurotrophic support through neurturin gene delivery in the nigro-striatal pathway. These pioneer clinical trials demonstrated the safety and tolerability of rAAV delivery in the human brain at moderate doses. Therapeutic effects however, were modest, emphasizing the need for higher doses of the therapeutic transgene product which could be achieved using more efficient vectors or expression cassettes. This will require re-addressing pharmacological aspects, with attention to which cases require either localized and cell-type specific expression or efficient brain-wide transgene expression, and when it is necessary to modulate or terminate the administration of transgene product. The ongoing development of targeted and regulated rAAV vectors is described. © 2013 The British Pharmacological Society., SCOPUS: ar.j, FLWIN, info:eu-repo/semantics/published

[no abstract]

Background: Pompe disease (Glycogen storage disease type II, GSD II, acid alpha-glucosidase deficiency, acid maltase deficiency, OMIM # 232300) is an autosomal-recessive lysosomal storage disorder due to a deficiency of acid alpha-glucosidase (GAA, acid maltase, EC 3.2.1.20, Swiss-Prot P10253). Clinical manifestations are dominated by progressive weakness of skeletal muscle throughout the clinical spectrum. In addition, the classic infantile form is characterised by hypertrophic cardiomyopathy. Methods. In a cross-sectional single-centre study we clinically assessed 3 patients with classic infantile Pompe disease and 39 patients with non-classic presentations, measured their acid alpha-glucosidase activities and analysed their GAA genes. Results: Classic infantile patients had nearly absent residual enzyme activities and a typical clinical course with hypertrophic cardiomyopathy until the beginning of therapy. The disease manifestations in non-classic patients were heterogeneous. There was a broad variability in the decline of locomotive and respiratory function. The age of onset ranged from birth to late adulthood and correlated with enzyme activities. Molecular analysis revealed as many as 33 different mutations, 14 of which are novel. All classic infantile patients had two severe mutations. The most common mutation in the non-classic group was c.-32-13T>G. It was associated with a milder course in this subgroup. Conclusions: Disease manifestation strongly correlates with the nature of the GAA mutations, while the variable progression in non-classic Pompe disease is likely to be explained by yet unknown modifying factors. This study provides the first comprehensive dataset on the clinical course and the mutational spectrum of Pompe disease in Germany.

Gene therapy is a fundamentally novel therapeutic approach that involves introducing genetic material into target cells in order to fight or prevent disease. A number of different strategies of gene therapy are tested at experimental and clinical levels, including: a) replacing a mutated gene that causes disease with a healthy copy of the gene, b) inactivating a mutated gene that its improper function causes pathogenesis, c) introducing a new gene coding a therapeutic compound to fight a disease, d) introducing to the target organ an enzyme converting an inactive pro-drug to its cytotoxic metabolite. In gene therapy, the transcriptional machinery of the patient is used to produce the active factor that exerts the intended therapeutic effect, ideally in a permanent, tissue-specific and manageable way. The liver is a major target for gene therapy, presenting inherited metabolic defects of single-gene etiology, but also severe multifactorial pathologies with limited therapeutic options such as hepatocellular carcinoma. The initial promising results from gene therapy strategies in liver diseases were followed by skepticism on the actual clinical value due to specificity, efficacy, toxicity and immune limitations, but are recently re-evaluated due to progress in vector technology and monitoring techniques. The significant amount of experimental data along with the available information from clinical trials are systematically reviewed here and presented per pathological entity. Finally, future perspectives of gene therapy protocols in hepatology are summarized. © 2012 Bentham Science Publishers.

Gene therapy is a fundamentally novel therapeutic approach that involves introducing genetic material into target cells in order to fight or prevent disease. A number of different strategies of gene therapy are tested at experimental and clinical levels, including: a) replacing a mutated gene that causes disease with a healthy copy of the gene, b) inactivating a mutated gene that its improper function causes pathogenesis, c) introducing a new gene coding a therapeutic compound to fight a disease, d) introducing to the target organ an enzyme converting an inactive pro-drug to its cytotoxic metabolite. In gene therapy, the transcriptional machinery of the patient is used to produce the active factor that exerts the intended therapeutic effect, ideally in a permanent, tissue-specific and manageable way. The liver is a major target for gene therapy, presenting inherited metabolic defects of single-gene etiology, but also severe multifactorial pathologies with limited therapeutic options such as hepatocellular carcinoma. The initial promising results from gene therapy strategies in liver diseases were followed by skepticism on the actual clinical value due to specificity, efficacy, toxicity and immune limitations, but are recently re-evaluated due to progress in vector technology and monitoring techniques. The significant amount of experimental data along with the available information from clinical trials are systematically reviewed here and presented per pathological entity. Finally, future perspectives of gene therapy protocols in hepatology are summarized. © 2012 Bentham Science Publishers.

[no abstract]

Introduction. Mucopolysaccharidoses are a group of infrequent disorders caused by the lysosomal deposit of glycosaminoglycans. Its incidence is quite variable among the countries where it has been documented. In Brazil, disorder frequencies have been reported, but in Colombia information on themis scarce.Objectives. The frequency and spatial aggregations of the mucopolysaccharidoses were estimated by a retrospective study in two central Colombian provinces.Materials and methods. The records of patients and live newborns between 1998-2007 were reviewed from several reference institutions for genetic diseases. From these records, the frequencies for each mucopolysaccharidosis were estimated. The spatial aggregation of the cases was analyzed using the SaTScan software.Results. The combined frequency for all the mucopolysaccharidoses was 1.98 cases per 100,000 livenewborns. MPS IV had the highest frequency with 0.68 cases per 100,000 live newborns and MPS III showed a lower frequency of 0.17/100,000. Three spatial aggregation areas were indicated for MPS I,MPS III and MPS IV.Conclusion. The combined frequency for all the mucopolysaccharidoses has been reported, with type IV the most frequent and the type VII in second place. The data herein constitute a record subset and, in spite of the difficulties inherent to the data retrieval in Colombia, they are a valid estimate of the frequencies of these diseases in central Colombia. doi: http://dx.doi.org/10.7705/biomedica.v32i4.574, Introducción. Las mucopolisacaridosis son enfermedades poco frecuentes de depósito lisosómico de glucosaminoglucanos, con datos variables sobre su incidencia en diferentes países a nivel mundial. En Latinoamérica hay reportes de frecuencias en Brasil, pero en Colombia la información es escasa.Objetivos. Estimar las frecuencias de las mucopolisacaridosis mediante un estudio retrospectivo en los departamentos de Cundinamarca y Boyacá, y estimar la agregación espacial de los casos en estos mismos departamentos.Materiales y métodos. Se revisaron los registros de pacientes de diferentes instituciones de referencia para enfermedades genéticas, así como los registros de nacimientos vivos entre 1998 y 2007. Con base en ellos, se estimaron las frecuencias para cada tipo de mucopolisacaridosis. Se analizó la agregación espacial de los casos utilizando el programa SaTScan™.Resultados. La frecuencia combinada para todas las mucopolisacaridosis fue de 1,98 casos por 100.000 nacidos vivos. La mayor frecuencia fue para la de tipo IV, con 0,68 casos por 100.000 nacidos vivos, mientras que la III fue la menor, con 0,17 casos. Se encontraron tres posibles áreas de agregación espacial para las mucopolisacaridosis I, III y IV.Conclusión. La frecuencia combinada para todas las mucopolisacaridosis se encuentra dentro delos rangos reportados en la literatura científica, siendo la de tipo IV la más frecuente y la de tipo VII la menos frecuente. Aunque los datos aquí reportados podrían corresponder a un subregistro, dadas las dificultades inherentes a la recolección de la información en nuestro país, consideramos que son un estimativo válido de las frecuencias de estas enfermedades. doi: http://dx.doi.org/10.7705/biomedica.v32i4.574

This paper reports that cocaine may induce a lysosomal storage disorder. Indeed, culture of Rat-1 fibroblasts with 250-500 microM cocaine induced after 2-3 days a major accumulation in lysosomes of electron-dense lamellar structures. By subcellular fractionation, this was reflected by a selective decrease of the buoyant density of several lysosomal enzymes, indicating lysosomal lipid overload. Biochemical analysis confirmed an increased cellular content of major phospholipids and sphingomyelin, but not of cholesterol. Cocaine, a membrane-permeant weak base, is concentrated by acidotropic sequestration, because its accumulation was abrogated by the proton ionophore, monensin and the vacuolar ATPase inhibitor, bafilomycin A1. At its estimated lysosomal concentration, cocaine almost completely inhibited phospholipase A1 activity on liposomes. Cell incubation with cocaine, but not with its inactive metabolite, benzoylecgonine, rapidly inactivated acid sphingomyelinase, as reflected by a 10-fold decrease in Vmax with identical Km. Acid sphingomyelinase inactivation was fully prevented by the thiol proteinases inhibitors, leupeptin and E64, indicating that cocaine induces selective sphingomyelinase proteolysis. Upon cocaine removal, acid sphingomyelinase activity was rapidly restored, pointing to its fast turnover. In contrast, the cellular content of several other lysosomal hydrolases was increased up to 2-fold. Together, these data show that acidotropic accumulation of cocaine in lysosomes rapidly inhibits acid phospholipase A1 and inactivates acid sphingomyelinase, which can explain induction of a mixed lysosomal lipidosis.

Patients with lysosomal storage disorders have visceral, skeletal, and neurological abnormalities and a limited life expectancy. Bone marrow transplantation has been used to correct the metabolic defects and leads to metabolic improvements in most patients. However, the long-term effect of such therapy is uncertain. We analysed the data from 63 patients transplanted for lysosomal storage diseases. The transplant-related mortality was 10% if an HLA-identical sibling marrow donor was available (n = 40) and 20-25% if mismatched tissue was used. Data on the effect of bone marrow transplantation on biochemical and clinical disease variables were available in 29 of the 63. 28 had a follow-up duration of 1.0-10.2 years; 1 patient died of disease progression in the first year after stable engraftment. 13 patients who had severe neurological symptoms at the time of transplantation showed disease progression. Engraftment of bone marrow in 5 patients with non-neuronopathic Gaucher's disease led to complete disappearance of symptoms. 11 patients had skeletal symptoms because of various mucopolysaccharidoses (MPSs). There was stabilisation of the skeletal lesions during the observation period of 1.4-6.4 years, but none of the patients showed significant regression of the skeletal symptoms. The visceral features (hepatosplenomegaly, cardiac hypertrophy, and upper airway obstruction) in these patients abated after transplantation. We could not evaluate the biochemical and clinical variables in 34 patients because of graft rejection, transplant-related mortality, or follow-up of less than 1 year. There were significant beneficial effects of bone marrow transplantation in patients with non-neuronopathic Gaucher's disease. Stabilisation of disease was observed in patients with MPS-I and MPS-II; this potential benefit needs to be confirmed by longer follow-up. Bone marrow transplantation was not effective if severe neurological symptoms were already present at the time of transplantat

The history of lysosomal storage diseases dates back to the end of the last century when the first clinical reports appeared of patients suffering from these genetic, metabolic disorders (Tay, 1881; Gaucher, 1882; Sachs, 1887; Fabry, 1898). About seventy years wouid pass before the term 11 "lysosome" was introduced by De Duve and co-workers (1955, 1965) to indicate a membrane-surrounded cytoplasmic particle containing acid hydrolases that was isolated by centrifugal cell fractionation. Later, the lysosomes were cytochemically demonstrated by Novikoff (1961) using an appropriate staining reaction for acid phosphatase and some other acid hydrolases. In the period that followed an impressive amount of work has been carried out on the structure and function of lysosomes (see for review Dingle and Fell, 1969-1975) and at present a few dozen of different acid hydrolases is known to be localized within this organe-lle. The main function of the lysosomal enzymes is the degradation of material that is enclosed in secondary lysosomes by fusion of the primary lysosome with hetero- and autophagosomes or by other processes.

The history of lysosomal storage diseases dates back to the end of the last century when the first clinical reports appeared of patients suffering from these genetic, metabolic disorders (Tay, 1881; Gaucher, 1882; Sachs, 1887; Fabry, 1898). About seventy years wouid pass before the term 11 "lysosome" was introduced by De Duve and co-workers (1955, 1965) to indicate a membrane-surrounded cytoplasmic particle containing acid hydrolases that was isolated by centrifugal cell fractionation. Later, the lysosomes were cytochemically demonstrated by Novikoff (1961) using an appropriate staining reaction for acid phosphatase and some other acid hydrolases. In the period that followed an impressive amount of work has been carried out on the structure and function of lysosomes (see for review Dingle and Fell, 1969-1975) and at present a few dozen of different acid hydrolases is known to be localized within this organe-lle. The main function of the lysosomal enzymes is the degradation of material that is enclosed in secondary lysosomes by fusion of the primary lysosome with hetero- and autophagosomes or by other processes.

Copyright © 2018 Solovyeva, Shaimardanova, Chulpanova, Kitaeva, Chakrabarti and Rizvanov. Tay-Sachs disease belongs to the group of autosomal-recessive lysosomal storage metabolic disorders. This disease is caused by β-hexosaminidase A (HexA) enzyme deficiency due to various mutations in α-subunit gene of this enzyme, resulting in GM2 ganglioside accumulation predominantly in lysosomes of nerve cells. Tay-Sachs disease is characterized by acute neurodegeneration preceded by activated microglia expansion, macrophage and astrocyte activation along with inflammatory mediator production. In most cases, the disease manifests itself during infancy, the “infantile form,” which characterizes the most severe disorders of the nervous system. The juvenile form, the symptoms of which appear in adolescence, and the most rare form with late onset of symptoms in adulthood are also described. The typical features of Tay-Sachs disease are muscle weakness, ataxia, speech, and mental disorders. Clinical symptom severity depends on residual HexA enzymatic activity associated with some mutations. Currently, Tay-Sachs disease treatment is based on symptom relief and, in case of the late-onset form, on the delay of progression. There are also clinical reports of substrate reduction therapy using miglustat and bone marrow or hematopoietic stem cell transplantation. At the development stage there are methods of Tay-Sachs disease gene therapy using adeno- or adeno-associated viruses as vectors for the delivery of cDNA encoding α and β HexA subunit genes. Effectiveness of this approach is evaluated in α or β HexA subunit defective model mice or Jacob sheep, in which Tay-Sachs disease arises spontaneously and is characterized by the same pathological features as in humans. This review discusses the possibilities of new therapeutic strategies in Tay-Sachs disease therapy aimed at preventing neurodegeneration and neuroinflammation.