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Karmi’el, Israel

Benmoyal-Segal L.,Hebrew University of Jerusalem | Soreq L.,Hebrew University | Ben-Shaul Y.,Hebrew University | Ben-Ari S.,Hebrew University of Jerusalem | And 6 more authors.
Neurodegenerative Diseases | Year: 2012

Background/Objective: Environmental exposure to anti-acetylcholinesterases (AChEs) aggravates the risk of Parkinsonism due to currently unclear mechanism(s). We explored the possibility that the brain's capacity to induce a widespread adaptive alternative splicing response to such exposure may be involved. Methods: Following exposure to the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), brain region transcriptome profiles were tested. Results: Changes in transcript profiles, alternative splicing patterns and splicing-related gene categories were identified. Engineered mice over-expressing the protective AChE-R splice variant showed less total changes but more splicing-related ones than hypersensitive AChE-S over-expressors with similarly increased hydrolytic activities. Following MPTP exposure, the substantia nigra and prefrontal cortex (PFC) of both strains showed a nuclear increase in the splicing factor ASF/SF2 protein. Furthermore, intravenous injection with highly purified recombinant human AChE-R changed transcript profiles in the striatum. Conclusions: Our findings are compatible with the working hypothesis that inherited or acquired alternative splicing deficits may promote parkinsonism, and we propose adaptive alternative splicing as a strategy for attenuating its progression. © 2011 S. Karger AG, Basel.

Bracoud L.,BioClinica | Ahmad H.,BioClinica | Brill-Almon E.,Protalix Biotherapeutics | Chertkoff R.,Protalix Biotherapeutics
Blood Cells, Molecules, and Diseases | Year: 2011

Purpose: To achieve minimal inter-observer variability in assessment of spleen and liver volume changes using a novel MRI reading method in the context of a phase III clinical trial of a new therapy for Gaucher disease. Materials and methods: Abdominal MRI examinations at screening and after 6 and 9. months' exposure to a novel plant-cell-derived recombinant enzyme, taliglucerase alfa, were taken in 31 patients with Gaucher disease and at least 8-fold greater than expected splenomegaly. Transverse T2, T1, and in/out-of-phase, and coronal T1 sequences were performed using standardized settings across 11 sites globally. Spleen and liver volumes were semi-automatically delineated using an automatic segmentation algorithm followed by manual correction by experienced technologists using advanced editing tools. Data of all randomized patients were then submitted for efficacy evaluation to two independent experts blinded to time-point and treatment. Results: Mean (± SD) percent variability over all time-points was 0.30%. ± 0.46% for spleen and 0.53%. ± 0.69% for liver using 178 spleen and liver volumes measured twice. Adjudication due to ≥ 5% variability between observers was not required. Conclusion: The measurement method was found to be precise in monitoring spleen and liver volume changes over time, with a much lower variability than traditional manual methods, supporting the accuracy of the results. Given the observed minimal variability rates among multiple readers, a single read of each volume would be sufficient. © 2010 Elsevier Inc.

Brumshtein B.,Weizmann Institute of Science | Aguilar-Moncayo M.,University of Seville | Benito J.M.,University of Seville | Garcia Fernandez J.M.,University of Seville | And 6 more authors.
Organic and Biomolecular Chemistry | Year: 2011

Cyclodextrin-based host-guest chemistry has been exploited to facilitate co-crystallization of recombinant human acid β-glucosidase (β-glucocerebrosidase, GlcCerase) with amphiphilic bicyclic nojirimycin analogues of the sp2-iminosugar type. Attempts to co-crystallize GlcCerase with 5-N,6-O-[N′-(n-octyl)iminomethylidene]nojirimycin (NOI-NJ) or with 5-N,6-S-[N′-(n-octyl)iminomethylidene]-6-thionojirimycin (6S-NOI-NJ), two potent inhibitors of the enzyme with promising pharmacological chaperone activity for several Gaucher disease-associated mutations, were unsuccessful probably due to the formation of aggregates that increase the heterogeneity of the sample and affect nucleation and growth of crystals. Cyclomaltoheptaose (β-cyclodextrin, βCD) efficiently captures NOI-NJ and 6S-NOI-NJ in aqueous media to form inclusion complexes in which the lipophilic tail is accommodated in the hydrophobic cavity of the cyclooligosaccharide. The dissociation constant of the complex of the amphiphilic sp2-iminosugars with βCD is two orders of magnitude higher than that of the corresponding complex with GlcCerase, allowing the efficient transfer of the inhibitor from the βCD cavity to the GlcCerase active site. Enzyme-inhibitor complexes suitable for X-ray analysis were thus grown in the presence of βCD. In contrast to what was previously observed for the complex of GlcCerase with the more basic derivative, 6-amino-6-deoxy-5-N,6-N-[N′-(n-octyl)iminomethylidene]nojirimycin (6N-NOI-NJ), the β-anomers of both NOI-NJ and 6S-NOI-NJ were seen in the active site, even though the α-anomer was exclusively detected both in aqueous solution and in the corresponding βCD:sp2-iminosugar complexes. Our results further suggest that cyclodextrin derivatives might serve as suitable delivery systems of amphiphilic glycosidase inhibitors in a biomedical context. © 2011 The Royal Society of Chemistry.

Zimran A.,Hebrew University of Jerusalem | Brill-Almon E.,Protalix Biotherapeutics | Chertkoff R.,Protalix Biotherapeutics | Petakov M.,University of Belgrade | And 17 more authors.
Blood | Year: 2011

Taliglucerase alfa (Protalix Biotherapeutics, Carmiel, Israel) is a novel plant cell-derived recombinant human β-glucocerebrosidase for Gaucher disease. A phase 3, double-blind, randomized, parallelgroup, comparison-dose (30 vs 60 U/kg body weight/infusion) multinational clinical trial was undertaken. Institutional review board approvals were received. A 9-month, 20-infusion trial used inclusion/exclusion criteria in treatmentnaive adult patients with splenomegaly and thrombocytopenia. Safety end points were drug-related adverse events: Ab formation and hypersensitivity reactions. Primary efficacy end point was reduction in splenic volume measured by magnetic resonance imaging. Secondary end points were: changes in hemoglobin, hepatic volume, and platelet counts. Exploratory parameters included biomarkers and bone imaging. Twenty-nine patients (11 centers) completed the protocol. There were no serious adverse events; drug-related adverse events were mild/moderate and transient. Two patients (6%) developed non-neutralizing IgG Abs; 2 other patients (6%) developed hypersensitivity reactions. Statistically significant spleen reductionwas achieved at 9 months: 26.9% (95% confidence interval [CI]: -31.9, -21.8) in the 30-unit dose group and 38.0% (95% CI: -43.4, -32.8) in the 60-unit dose group (both P < .0001); and in all secondary efficacy end point measures, except platelet counts at the lower dose. These results support safety and efficacy of taliglucerase alfa for Gaucher disease. This study was registered at www. clinicaltrials.gov as NCT00376168. © 2011 by The American Society of Hematology.

Pastores G.M.,New York University | Petakov M.,University of Belgrade | Petakov M.,Institute of Endocrinology | Giraldo P.,Hospital Universitario Miguel Servet | And 9 more authors.
Blood Cells, Molecules, and Diseases | Year: 2014

Taliglucerase alfa is a β-glucosidase enzyme replacement therapy (ERT) approved in the US and other countries for the treatment of Gaucher disease (GD) in adults and is approved in pediatric and adult patients in Australia and Canada. It is the first approved plant cell-expressed recombinant human protein. A Phase 3, multicenter, open-label, 9-month study assessed safety and efficacy of switching to taliglucerase alfa in adult and pediatric patients with GD treated with imiglucerase for at least the previous 2. years. Patients with stable disease were offered taliglucerase alfa treatment using the same dose (9-60. U/kg body weight) and regimen of administration (every 2. weeks) as imiglucerase. This report summarizes results from 26 adult and 5 pediatric patients who participated in the trial. Disease parameters (spleen and liver volumes, hemoglobin concentration, platelet count, and biomarker levels) remained stable through 9. months of treatment in adults and children following the switch from imiglucerase. All treatment-related adverse events were mild or moderate in severity and transient in nature. Exploratory parameters of linear growth and development showed positive outcomes in pediatric patients. These findings provide evidence of the efficacy and safety profile of taliglucerase alfa as an ERT for GD in patients previously treated with imiglucerase. This trial was registered at www.clinicaltrials.gov as # NCT00712348. © 2014 Elsevier Inc.

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