The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Angela Gritti - One of the best experts on this subject based on the ideXlab platform.
-
Novel bicistronic lentiviral vectors correct β-Hexosaminidase deficiency in neural and hematopoietic stem cells and progeny: implications for in vivo and ex vivo gene therapy of GM2 Gangliosidosis.
Neurobiology of disease, 2019Co-Authors: Francesca Ornaghi, Francesco Morena, Martina Bazzucchi, Sabata Martino, Davide Sala, Fabiana Tedeschi, Maria Chiara Maffia, Manuela Valsecchi, Massimo Aureli, Angela GrittiAbstract:The favorable outcome of in vivo and ex vivo gene therapy approaches in several Lysosomal Storage Diseases suggests that these treatment strategies might equally benefit GM2 Gangliosidosis. Tay-Sachs and Sandhoff disease (the main forms of GM2 Gangliosidosis) result from mutations in either the HEXA or HEXB genes encoding, respectively, the α- or β-subunits of the lysosomal β-Hexosaminidase enzyme. In physiological conditions, α- and β-subunits combine to generate β-Hexosaminidase A (HexA, αβ) and β-Hexosaminidase B (HexB, ββ). A major impairment to establishing in vivo or ex vivo gene therapy for GM2 Gangliosidosis is the need to synthesize the α- and β-subunits at high levels and with the correct stoichiometric ratio, and to safely deliver the therapeutic products to all affected tissues/organs. Here, we report the generation and in vitro validation of novel bicistronic lentiviral vectors (LVs) encoding for both the murine and human codon optimized Hexa and Hexb genes. We show that these LVs drive the safe and coordinate expression of the α- and β-subunits, leading to supranormal levels of β-Hexosaminidase activity with prevalent formation of a functional HexA in SD murine neurons and glia, murine bone marrow-derived hematopoietic stem/progenitor cells (HSPCs), and human SD fibroblasts. The restoration/overexpression of β-Hexosaminidase leads to the reduction of intracellular GM2 ganglioside storage in transduced and in cross-corrected SD murine neural progeny, indicating that the transgenic enzyme is secreted and functional. Importantly, bicistronic LVs safely and efficiently transduce human neurons/glia and CD34+ HSPCs, which are target and effector cells, respectively, in prospective in vivo and ex vivo GT approaches. We anticipate that these bicistronic LVs may overcome the current requirement of two vectors co-delivering the α- or β-subunits genes. Careful assessment of the safety and therapeutic potential of these bicistronic LVs in the SD murine model will pave the way to the clinical development of LV-based gene therapy for GM2 Gangliosidosis.
-
Integrated Computational Analysis Highlights unique miRNA Signatures in the Subventricular Zone and Striatum of GM2 Gangliosidosis Animal Models.
International journal of molecular sciences, 2019Co-Authors: Francesco Morena, Vasileios Oikonomou, Chiara Argentati, Martina Bazzucchi, Carla Emiliani, Angela Gritti, Sabata MartinoAbstract:This work explores for the first time the potential contribution of microRNAs (miRNAs) to the pathophysiology of the GM2 Gangliosidosis, a group of Lysosomal Storage Diseases. In spite of the genetic origin of GM2 Gangliosidosis, the cascade of events leading from the gene/protein defects to the cell dysfunction and death is not fully elucidated. At present, there is no cure for patients. Taking advantage of the animal models of two forms of GM2 Gangliosidosis, Tay-Sachs (TSD) and Sandhoff (SD) diseases, we performed a microRNA screening in the brain subventricular zone (SVZ) and striatum (STR), which feature the neurogenesis and neurodegeneration states, respectively, in adult mutant mice. We found abnormal expression of a panel of miRNAs involved in lipid metabolism, CNS development and homeostasis, and neuropathological processes, highlighting region- and disease-specific profiles of miRNA expression. Moreover, by using a computational analysis approach, we identified a unique disease- (SD or TSD) and brain region-specific (SVZ vs. STR) miRNAs signatures of predicted networks potentially related to the pathogenesis of the diseases. These results may contribute to the understanding of GM2 Gangliosidosis pathophysiology, with the aim of developing effective treatments.
Hitoshi Sakuraba - One of the best experts on this subject based on the ideXlab platform.
-
Structural basis of the GM2 Gangliosidosis B variant.
Journal of human genetics, 2003Co-Authors: Fumiko Matsuzawa, Kousaku Ohno, Hitoshi Sakuraba, Akemi Tanaka, Seiichi Aikawa, Hoang Thi Ngoc Lan, Yuko Sugimoto, Haruaki Ninomiya, Hirofumi DoiAbstract:To study the structural basis of the GM2 Gangliosidosis B variant, we constructed the three-dimensional structures of the human β-hexosaminidase α-subunit and the heterodimer of the α- and β-subunits, Hex A, by homology modeling. The α-subunit is composed of two domains, domains I and II. Nine mutant models due to specific missense mutations were constructed as well and compared with the wild type to determine structural defects. These nine mutations were divided into five groups according to structural defects. R178H is deduced to affect the active site directly, because R178 is important for binding to the substrate. C458Y and W420C are predicted to cause drastic structural changes in the barrel structure carrying the active site pocket. R504C/H is deduced to introduce a disruption of an essential binding with D494 in the β-subunit for dimerization. R499C/H, located in an extra-helix, is deduced to disrupt hydrogen bonds with domain I and the barrel. R170W and L484P are deduced to affect the interface between domains I and II, causing destabilization. The structural defects reflect the biochemical abnormalities of the disease.
-
GM2 Gangliosidosis AB VARIANT: CLINICAL AND BIOCHEMICAL STUDIES OF A JAPANESE PATIENT
Neurology, 1999Co-Authors: Hitoshi Sakuraba, Kohji Itoh, Michie Shimmoto, Kouichi Utsumi, Ryoichi Kase, Y. Hashimoto, T. Ozawa, Y. Ohwada, G. Imataka, M. EguchiAbstract:To determine the clinical features and biochemical basis of the first Japanese patient with the GM2 Gangliosidosis AB variant. The clinical manifestations and laboratory findings in the patient were investigated. Cultured fibroblasts from the patient were analyzed by means of immunofluorescence staining with an anti-GM2 ganglioside monoclonal antibody and thin-layer chromatography and immunostaining. GM1 ganglioside catabolism in cultured cells was analyzed by pulse labeling, and the amount of GM2 activator in cells was determined by Western blot analysis. Gene analysis was performed according to standard protocols. The patient showed progressive neurologic manifestations of quite early onset. Muscular weakness and hypotonia became evident by 1 month of age, and the patient then developed a startle reaction, severe psychomotor retardation, and myoclonic seizures. Immunocytochemical analysis clearly revealed the accumulation of GM2 ganglioside in cultured fibroblasts from the patient, and thin-layer chromatography confirmed it. Western blot and metabolic studies showed a complete deficiency of GM2 activator. Gene analysis did not reveal any mutations in the protein coding region of the GM2 activator gene. The clinical features and biochemical basis of this Japanese patient with GM2 Gangliosidosis AB variant were determined. Immunocytochemical analysis using cultured fibroblasts as samples is available for the diagnosis of this disease.
-
GM2 Gangliosidosis ab variant clinical and biochemical studies of a japanese patient
Neurology, 1999Co-Authors: Hitoshi Sakuraba, Kohji Itoh, Michie Shimmoto, Kouichi Utsumi, Ryoichi Kase, Y. Hashimoto, T. Ozawa, Y. Ohwada, G. Imataka, M. EguchiAbstract:Objective: To determine the clinical features and biochemical basis of the first Japanese patient with the GM2 Gangliosidosis AB variant. Methods: The clinical manifestations and laboratory findings in the patient were investigated. Cultured fibroblasts from the patient were analyzed by means of immunofluorescence staining with an anti-GM2 ganglioside monoclonal antibody and thin-layer chromatography and immunostaining. GM1 ganglioside catabolism in cultured cells was analyzed by pulse labeling, and the amount of GM2 activator in cells was determined by Western blot analysis. Gene analysis was performed according to standard protocols. Results: The patient showed progressive neurologic manifestations of quite early onset. Muscular weakness and hypotonia became evident by 1 month of age, and the patient then developed a startle reaction, severe psychomotor retardation, and myoclonic seizures. Immunocytochemical analysis clearly revealed the accumulation of GM2 ganglioside in cultured fibroblasts from the patient, and thin-layer chromatography confirmed it. Western blot and metabolic studies showed a complete deficiency of GM2 activator. Gene analysis did not reveal any mutations in the protein coding region of the GM2 activator gene. Conclusion: The clinical features and biochemical basis of this Japanese patient with GM2 Gangliosidosis AB variant were determined. Immunocytochemical analysis using cultured fibroblasts as samples is available for the diagnosis of this disease.
-
Prenatal diagnosis of GM2-Gangliosidosis: Immunofluorescence analysis of ganglioside GM2 in cultured amniocytes by confocal laser scanning microscopy
Brain & development, 1993Co-Authors: Hitoshi Sakuraba, Kohji Itoh, Masaharu Kotani, Tadashi Tai, Hideo Yamada, Kenji Kurosawa, Yoshikazu Kuroki, Hiroshi Suzuki, Toru Utsunomiya, Hisako InoueAbstract:A confocal laser scanning microscopic system was used to detect the storage of ganglioside GM2 in Tay-Sachs fibroblasts and amniocytes. The diagnosis of the disease was confirmed by counting immunoreactive cells or by digital imaging analysis. This novel system facilitates the prenatal diagnosis of GM2-Gangliosidosis.
Kohji Itoh - One of the best experts on this subject based on the ideXlab platform.
-
Thymic involution and corticosterone level in Sandhoff disease model mice: new aspects the pathogenesis of GM2 Gangliosidosis.
Journal of inherited metabolic disease, 2011Co-Authors: Kazuhiko Matsuoka, Daisuke Tsuji, Takao Taki, Kohji ItohAbstract:Sandhoff disease (SD) is a lysosomal disease caused by a mutation of the HEXB gene associated with excessive accumulation of GM2 ganglioside (GM2) in lysosomes and neurological manifestations. Production of autoantibodies against the accumulated gangliosides has been reported to be involved in the progressive pathogenesis of GM2 Gangliosidosis, although the underlying mechanism has not been fully elucidated. The thymus is the key organ in the acquired immune system including the development of autoantibodies. We showed here that thymic involution and an increase in cell death in the organ occur in SD model mice at a late stage of the pathogenesis. Dramatic increases in the populations of Annexin-V+ cells and terminal deoxynucletidyl transferase dUTP nick end labeling (TUNEL) + cells were observed throughout the thymuses of 15-week old SD mice. Enhanced caspase-3/7 activation, but not that of caspase-1/4, -6 ,-8, or −9, was also demonstrated. Furthermore, the serum level of corticosterone, a potent inducer of apoptosis of thymocytes, was elevated during the same period of apoptosis. Our studies suggested that an increase in endocrine corticosterone may be one of the causes that accelerate the apoptosis of thymocytes leading to thymic involution in GM2 Gangliosidosis, and thus can be used as a disease marker for evaluation of the thymic condition and disease progression.
-
GM2 Gangliosidosis AB VARIANT: CLINICAL AND BIOCHEMICAL STUDIES OF A JAPANESE PATIENT
Neurology, 1999Co-Authors: Hitoshi Sakuraba, Kohji Itoh, Michie Shimmoto, Kouichi Utsumi, Ryoichi Kase, Y. Hashimoto, T. Ozawa, Y. Ohwada, G. Imataka, M. EguchiAbstract:To determine the clinical features and biochemical basis of the first Japanese patient with the GM2 Gangliosidosis AB variant. The clinical manifestations and laboratory findings in the patient were investigated. Cultured fibroblasts from the patient were analyzed by means of immunofluorescence staining with an anti-GM2 ganglioside monoclonal antibody and thin-layer chromatography and immunostaining. GM1 ganglioside catabolism in cultured cells was analyzed by pulse labeling, and the amount of GM2 activator in cells was determined by Western blot analysis. Gene analysis was performed according to standard protocols. The patient showed progressive neurologic manifestations of quite early onset. Muscular weakness and hypotonia became evident by 1 month of age, and the patient then developed a startle reaction, severe psychomotor retardation, and myoclonic seizures. Immunocytochemical analysis clearly revealed the accumulation of GM2 ganglioside in cultured fibroblasts from the patient, and thin-layer chromatography confirmed it. Western blot and metabolic studies showed a complete deficiency of GM2 activator. Gene analysis did not reveal any mutations in the protein coding region of the GM2 activator gene. The clinical features and biochemical basis of this Japanese patient with GM2 Gangliosidosis AB variant were determined. Immunocytochemical analysis using cultured fibroblasts as samples is available for the diagnosis of this disease.
-
GM2 Gangliosidosis ab variant clinical and biochemical studies of a japanese patient
Neurology, 1999Co-Authors: Hitoshi Sakuraba, Kohji Itoh, Michie Shimmoto, Kouichi Utsumi, Ryoichi Kase, Y. Hashimoto, T. Ozawa, Y. Ohwada, G. Imataka, M. EguchiAbstract:Objective: To determine the clinical features and biochemical basis of the first Japanese patient with the GM2 Gangliosidosis AB variant. Methods: The clinical manifestations and laboratory findings in the patient were investigated. Cultured fibroblasts from the patient were analyzed by means of immunofluorescence staining with an anti-GM2 ganglioside monoclonal antibody and thin-layer chromatography and immunostaining. GM1 ganglioside catabolism in cultured cells was analyzed by pulse labeling, and the amount of GM2 activator in cells was determined by Western blot analysis. Gene analysis was performed according to standard protocols. Results: The patient showed progressive neurologic manifestations of quite early onset. Muscular weakness and hypotonia became evident by 1 month of age, and the patient then developed a startle reaction, severe psychomotor retardation, and myoclonic seizures. Immunocytochemical analysis clearly revealed the accumulation of GM2 ganglioside in cultured fibroblasts from the patient, and thin-layer chromatography confirmed it. Western blot and metabolic studies showed a complete deficiency of GM2 activator. Gene analysis did not reveal any mutations in the protein coding region of the GM2 activator gene. Conclusion: The clinical features and biochemical basis of this Japanese patient with GM2 Gangliosidosis AB variant were determined. Immunocytochemical analysis using cultured fibroblasts as samples is available for the diagnosis of this disease.
-
Prenatal diagnosis of GM2-Gangliosidosis: Immunofluorescence analysis of ganglioside GM2 in cultured amniocytes by confocal laser scanning microscopy
Brain & development, 1993Co-Authors: Hitoshi Sakuraba, Kohji Itoh, Masaharu Kotani, Tadashi Tai, Hideo Yamada, Kenji Kurosawa, Yoshikazu Kuroki, Hiroshi Suzuki, Toru Utsunomiya, Hisako InoueAbstract:A confocal laser scanning microscopic system was used to detect the storage of ganglioside GM2 in Tay-Sachs fibroblasts and amniocytes. The diagnosis of the disease was confirmed by counting immunoreactive cells or by digital imaging analysis. This novel system facilitates the prenatal diagnosis of GM2-Gangliosidosis.
Eva Zaccariotto - One of the best experts on this subject based on the ideXlab platform.
-
genetics and therapies for GM2 Gangliosidosis
Current Gene Therapy, 2018Co-Authors: M B Cachongonzalez, Eva ZaccariottoAbstract:Tay-Sachs disease, caused by impaired β-N-acetylhexosaminidase activity, was the first GM2 Gangliosidosis to be studied and one of the most severe and earliest lysosomal diseases to be described. The condition, associated with the pathological build-up of GM2 ganglioside, has acquired almost iconic status and serves as a paradigm in the study of lysosomal storage diseases. Inherited as a classical autosomal recessive disorder, this global disease of the nervous system induces developmental arrest with regression of attained milestones; neurodegeneration progresses rapidly to cause premature death in young children. There is no effective treatment beyond palliative care, and while the genetic basis of GM2 Gangliosidosis is well established, the molecular and cellular events, from diseasecausing mutations and glycosphingolipid storage to disease manifestations, remain to be fully delineated. Several therapeutic approaches have been attempted in patients, including enzymatic augmentation, bone marrow transplantation, enzyme enhancement, and substrate reduction therapy. Hitherto, none of these stratagems has materially altered the course of the disease. Authentic animal models of GM2 gangliodidosis have facilitated in-depth evaluation of innovative applications such as gene transfer, which in contrast to other interventions, shows great promise. This review outlines current knowledge pertaining the pathobiology as well as potential innovative treatments for the GM2 gangliosidoses.
Fowzan S. Alkuraya - One of the best experts on this subject based on the ideXlab platform.
-
GM2 Gangliosidosis in Saudi Arabia: Multiple Mutations and Considerations for Future Carrier Screening
American Journal of Medical Genetics Part A, 2011Co-Authors: Namik Kaya, Mohammad Al Owain, Nada Abudheim, Jawaher Al Zahrani, Dilek Colak, Moeen Al Sayed, Aysel Milanlioglu, Pinar Ozand, Fowzan S. AlkurayaAbstract:The GM2 gangliosidose, Tay–Sachs and Sandhoff diseases, are a class of lysosomal storage diseases in which relentless neurodegeneration results in devastating neurological disability and premature death. Primary prevention is the most effective intervention since no effective therapy is currently available. An extremely successful model for the prevention of GM2 Gangliosidosis in the Ashkenazi Jewish community is largely attributable to the very limited number of founder mutations in that population. Consistent with our previous observation of allelic heterogeneity in consanguineous populations, we show here that these diseases are largely caused by private mutations which present a major obstacle in replicating the Ashkenazi success story. Alternative solutions are proposed which can also be implemented for other autosomal recessive diseases in our population. © 2011 Wiley-Liss, Inc.
-
GM2 Gangliosidosis in Saudi Arabia: multiple mutations and considerations for future carrier screening.
American journal of medical genetics. Part A, 2011Co-Authors: Namik Kaya, Mohammad Al Owain, Nada Abudheim, Dilek Colak, Aysel Milanlioglu, Pinar Ozand, Jawaher Al-zahrani, Moeen Al-sayed, Fowzan S. AlkurayaAbstract:The GM2 gangliosidose, Tay-Sachs and Sandhoff diseases, are a class of lysosomal storage diseases in which relentless neurodegeneration results in devastating neurological disability and premature death. Primary prevention is the most effective intervention since no effective therapy is currently available. An extremely successful model for the prevention of GM2 Gangliosidosis in the Ashkenazi Jewish community is largely attributable to the very limited number of founder mutations in that population. Consistent with our previous observation of allelic heterogeneity in consanguineous populations, we show here that these diseases are largely caused by private mutations which present a major obstacle in replicating the Ashkenazi success story. Alternative solutions are proposed which can also be implemented for other autosomal recessive diseases in our population.