27 research outputs found

    VOSYSmonitor, a TrustZone-based Hypervisor for ISO 26262 Mixed-critical System

    Get PDF
    With the emergence of multicore embedded System on Chip (SoC), the integration of several applications with different levels of criticality on the same platform is becoming increasingly popular. These platforms, known as mixed-criticality systems, need to meet numerous requirements (e.g. real-time constraints, multiple Operating Systems (OS) scheduling, pro- viding temporal and spatial isolation). In this context Virtual Open Systems has developed VOSYSmonitor, a thin software layer, which allows the co-execution of a safety-critical and non- critical applications on a single ARM-based multi-core SoC. This software element has been developed according to the ISO 26262 standard. One of the key aspects of this standard is the control of random and systematic failures, including the ones induced by faulty or aging hardware. In the case of a software component, the means to detect anomalies on the hardware are limited and depend on choices of the manufacturer (i.e. implementation of Dual redundant Core Lock step (DCLS)). However, the software is able to check a part of these failures. It can be by either reading the conïŹguration registers of a peripheral, or checking the sanity of a memory region. The purpose of this paper is to showcase how a safety-related software element (e.g. VOSYSmonitor) can detect and recover from failures, while ensuring that the safety-related goals are still reached

    An Orthotopic Model of Glioblastoma Is Resistant to Radiodynamic Therapy with 5-AminoLevulinic Acid

    Get PDF
    Radiosensitization of glioblastoma is a major ambition to increase the survival of this incurable cancer. The 5-aminolevulinic acid (5-ALA) is metabolized by the heme biosynthesis pathway. 5-ALA overload leads to the accumulation of the intermediate fluorescent metabolite protoporphyrin IX (PpIX) with a radiosensitization potential, never tested in a relevant model of glioblastoma. We used a patient-derived tumor cell line grafted orthotopically to create a brain tumor model. We evaluated tumor growth and tumor burden after different regimens of encephalic multifractionated radiation therapy with or without 5-ALA. A fractionation scheme of 5 × 2 Gy three times a week resulted in intermediate survival [48-62 days] compared to 0 Gy (15-24 days), 3 × 2 Gy (41-47 days) and, 5 × 3 Gy (73-83 days). Survival was correlated to tumor growth. Tumor growth and survival were similar after 5 × 2 Gy irradiations, regardless of 5-ALA treatment (RT group (53-67 days), RT+5-ALA group (40-74 days), HR = 1.57, p = 0.24). Spheroid growth and survival were diminished by radiotherapy in vitro, unchanged by 5-ALA pre-treatment, confirming the in vivo results. The analysis of two additional stem-like patient-derived cell lines confirmed the absence of radiosensitization by 5-ALA. Our study shows for the first time that in a preclinical tumor model relevant to human glioblastoma, treated as in clinical routine, 5-ALA administration, although leading to important accumulation of PpIX, does not potentiate radiotherapy

    On the Zwitterionic Nature of Gas-Phase Peptides and Protein Ions

    Get PDF
    Determining the total number of charged residues corresponding to a given value of net charge for peptides and proteins in gas phase is crucial for the interpretation of mass-spectrometry data, yet it is far from being understood. Here we show that a novel computational protocol based on force field and massive density functional calculations is able to reproduce the experimental facets of well investigated systems, such as angiotensin II, bradykinin, and tryptophan-cage. The protocol takes into account all of the possible protomers compatible with a given charge state. Our calculations predict that the low charge states are zwitterions, because the stabilization due to intramolecular hydrogen bonding and salt-bridges can compensate for the thermodynamic penalty deriving from deprotonation of acid residues. In contrast, high charge states may or may not be zwitterions because internal solvation might not compensate for the energy cost of charge separation

    Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk

    Get PDF
    The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project-imputed genotype data in up to similar to 370,000 women, we identify 389 independent signals (P <5 x 10(-8)) for age at menarche, a milestone in female pubertal development. In Icelandic data, these signals explain similar to 7.4% of the population variance in age at menarche, corresponding to similar to 25% of the estimated heritability. We implicate similar to 250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women and prostate cancer in men. In aggregate, our findings highlight the complexity of the genetic regulation of puberty timing and support causal links with cancer susceptibility

    Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk

    Get PDF
    The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project–imputed genotype data in up to ~370,000 women, we identify 389 independent signals (P < 5 × 10−8^{−8}) for age at menarche, a milestone in female pubertal development. In Icelandic data, these signals explain ~7.4% of the population variance in age at menarche, corresponding to ~25% of the estimated heritability. We implicate ~250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women and prostate cancer in men. In aggregate, our findings highlight the complexity of the genetic regulation of puberty timing and support causal links with cancer susceptibility

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

    Get PDF
    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Safety concerns regarding CRISPR-Cas9 gene therapy in red blood cells diseases

    No full text
    L’objectif de ce travail a Ă©tĂ© d’étudier la gĂ©notoxicitĂ© de la thĂ©rapie gĂ©nique par CRISPR (Clustered Regularly Interspaced Palindromic Repeats)-Cas9 (CRISPR associated protein) et de proposer une sĂ©curisation dans des modĂšles de maladies hĂ©rĂ©ditaires du GR, la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et les bĂ©ta-hĂ©moglobinopathies. Les bĂȘta-hĂ©moglobinopathies comprennent la drĂ©panocytose et la bĂȘta-thalassĂ©mie et sont les maladies monogĂ©niques les plus frĂ©quentes dans le monde contrairement Ă  la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale qui est trĂšs rare. La thĂ©rapie gĂ©nique pourrait ĂȘtre une approche thĂ©rapeutique prometteuse pour ces maladies graves. L'Ă©dition du gĂ©nome par CRISPR-Cas9 est revendiquĂ©e comme une alternative Ă  la thĂ©rapie gĂ©nique additive. Nous avons utilisĂ© les coupures doubles brins d’ADN induites par la nuclĂ©ase Cas9 au locus UROS pour Ă©diter la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et au locus bĂȘta-globine pour Ă©diter les bĂȘta-hĂ©moglobinopathies. Nous avons dĂ©montrĂ© qu'aprĂšs une seule coupures double brin d’ADN par CRISPR, les insertions-dĂ©lĂ©tions au site de coupure du locus UROS sur le chromosome 10, pouvaient ĂȘtre concomitantes de grandes dĂ©lĂ©tions chromosomiques inattendues dans des lignĂ©es cellulaires mais aussi dans des cellules primaires dĂ©ficientes pour TP53. Nous avons confirmĂ© ce rĂ©sultat au locus bĂȘta-globine sur le chromosome 11 dans une lignĂ©e cellulaire. De plus, dans les cellules souches hĂ©matopoĂŻĂ©tiques, nous avons dĂ©crit un autre type de gĂ©notoxicitĂ© au locus bĂȘta-globine : des pertes d'hĂ©tĂ©rozygotie copies neutres conduisant Ă  une disomie uniparentale partielle 11p15.5. Ces nouvelles donnĂ©es sont cruciales car les thĂ©rapies gĂ©niques basĂ©es sur CRISPR-Cas9 sont en cours pour les bĂȘta-hĂ©moglobinopathies chez les patients. Au total, ces effets secondaires sont Ă  prendre en compte pour la modĂ©lisation de maladies et pour la thĂ©rapie gĂ©nique. Nos donnĂ©es mettent en Ă©vidence la nĂ©cessitĂ© de contrĂŽler et d'amĂ©liorer la sĂ©curitĂ© de CRISPR-Cas9 et nous avons proposĂ© une alternative Ă  CRISPR-Cas9-nuclĂ©ase grĂące Ă  l'utilisation de la nickase dans une lignĂ©e cellulaire.The objective of this work was to study the genotoxicity of gene therapy by CRISPR (Clustered Regularly Interspaced Palindromic Repeats) -Cas9 (CRISPR Associated protein) and to propose safety in models of inherited red blood cell diseases, congenital erythropoietic porphyria and beta hemoglobinopathies. Beta-hemoglobinopathies include sickle cell disease and beta-thalassemia and are the most common monogenic diseases in the world unlike congenital erythropoietic porphyria, which is very rare. Gene therapy could be a promising therapeutic approach for these severe diseases. CRISPR-Cas9 mediated genome editing is claimed as an alternative to additive gene therapy. We used Cas9 nuclease-induced double-strand break DNA at the UROS locus to edit congenital erythropoietic porphyria and at the beta-globin locus to edit beta-hemoglobinopathies. We demonstrated, that after a single CRISPR-mediated double-strand break DNA, the on-target insertion-deletions at the UROS locus on the chromosome 10 could be concomitant to unexpected chromosomal large deletions in cell lines but also in primary cells deficient for TP53. We confirmed this concern at the beta-globin locus on chromosome 11 in cell line. Moreover, in hematopoietic stem cells, we described another kind of genotoxicity at the beta-globin locus: copy-neutral losses of heterozygosity leading to 11p15.5 partial uniparental disomy. These new data are crucial because CRISPR-Cas9-based gene therapies are just ongoing for beta-hemoglobinopathies in patients. Altogether, these side effects must be taken into account for disease modeling and for gene therapy. Our data highlight the need to control and improve CRISPR-Cas9 safety and we have proposed an alternative to CRISPR-Cas9-nuclease through the use of nickase in cell line

    Sécurisation de la thérapie génique par CRISPR-Cas9 dans les pathologies du globule rouge

    No full text
    The objective of this work was to study the genotoxicity of gene therapy by CRISPR (Clustered Regularly Interspaced Palindromic Repeats) -Cas9 (CRISPR Associated protein) and to propose safety in models of inherited red blood cell diseases, congenital erythropoietic porphyria and beta hemoglobinopathies. Beta-hemoglobinopathies include sickle cell disease and beta-thalassemia and are the most common monogenic diseases in the world unlike congenital erythropoietic porphyria, which is very rare. Gene therapy could be a promising therapeutic approach for these severe diseases. CRISPR-Cas9 mediated genome editing is claimed as an alternative to additive gene therapy. We used Cas9 nuclease-induced double-strand break DNA at the UROS locus to edit congenital erythropoietic porphyria and at the beta-globin locus to edit beta-hemoglobinopathies. We demonstrated, that after a single CRISPR-mediated double-strand break DNA, the on-target insertion-deletions at the UROS locus on the chromosome 10 could be concomitant to unexpected chromosomal large deletions in cell lines but also in primary cells deficient for TP53. We confirmed this concern at the beta-globin locus on chromosome 11 in cell line. Moreover, in hematopoietic stem cells, we described another kind of genotoxicity at the beta-globin locus: copy-neutral losses of heterozygosity leading to 11p15.5 partial uniparental disomy. These new data are crucial because CRISPR-Cas9-based gene therapies are just ongoing for beta-hemoglobinopathies in patients. Altogether, these side effects must be taken into account for disease modeling and for gene therapy. Our data highlight the need to control and improve CRISPR-Cas9 safety and we have proposed an alternative to CRISPR-Cas9-nuclease through the use of nickase in cell line.L’objectif de ce travail a Ă©tĂ© d’étudier la gĂ©notoxicitĂ© de la thĂ©rapie gĂ©nique par CRISPR (Clustered Regularly Interspaced Palindromic Repeats)-Cas9 (CRISPR associated protein) et de proposer une sĂ©curisation dans des modĂšles de maladies hĂ©rĂ©ditaires du GR, la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et les bĂ©ta-hĂ©moglobinopathies. Les bĂȘta-hĂ©moglobinopathies comprennent la drĂ©panocytose et la bĂȘta-thalassĂ©mie et sont les maladies monogĂ©niques les plus frĂ©quentes dans le monde contrairement Ă  la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale qui est trĂšs rare. La thĂ©rapie gĂ©nique pourrait ĂȘtre une approche thĂ©rapeutique prometteuse pour ces maladies graves. L'Ă©dition du gĂ©nome par CRISPR-Cas9 est revendiquĂ©e comme une alternative Ă  la thĂ©rapie gĂ©nique additive. Nous avons utilisĂ© les coupures doubles brins d’ADN induites par la nuclĂ©ase Cas9 au locus UROS pour Ă©diter la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et au locus bĂȘta-globine pour Ă©diter les bĂȘta-hĂ©moglobinopathies. Nous avons dĂ©montrĂ© qu'aprĂšs une seule coupures double brin d’ADN par CRISPR, les insertions-dĂ©lĂ©tions au site de coupure du locus UROS sur le chromosome 10, pouvaient ĂȘtre concomitantes de grandes dĂ©lĂ©tions chromosomiques inattendues dans des lignĂ©es cellulaires mais aussi dans des cellules primaires dĂ©ficientes pour TP53. Nous avons confirmĂ© ce rĂ©sultat au locus bĂȘta-globine sur le chromosome 11 dans une lignĂ©e cellulaire. De plus, dans les cellules souches hĂ©matopoĂŻĂ©tiques, nous avons dĂ©crit un autre type de gĂ©notoxicitĂ© au locus bĂȘta-globine : des pertes d'hĂ©tĂ©rozygotie copies neutres conduisant Ă  une disomie uniparentale partielle 11p15.5. Ces nouvelles donnĂ©es sont cruciales car les thĂ©rapies gĂ©niques basĂ©es sur CRISPR-Cas9 sont en cours pour les bĂȘta-hĂ©moglobinopathies chez les patients. Au total, ces effets secondaires sont Ă  prendre en compte pour la modĂ©lisation de maladies et pour la thĂ©rapie gĂ©nique. Nos donnĂ©es mettent en Ă©vidence la nĂ©cessitĂ© de contrĂŽler et d'amĂ©liorer la sĂ©curitĂ© de CRISPR-Cas9 et nous avons proposĂ© une alternative Ă  CRISPR-Cas9-nuclĂ©ase grĂące Ă  l'utilisation de la nickase dans une lignĂ©e cellulaire

    Safety concerns regarding CRISPR-Cas9 gene therapy in red blood cells diseases

    No full text
    L’objectif de ce travail a Ă©tĂ© d’étudier la gĂ©notoxicitĂ© de la thĂ©rapie gĂ©nique par CRISPR (Clustered Regularly Interspaced Palindromic Repeats)-Cas9 (CRISPR associated protein) et de proposer une sĂ©curisation dans des modĂšles de maladies hĂ©rĂ©ditaires du GR, la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et les bĂ©ta-hĂ©moglobinopathies. Les bĂȘta-hĂ©moglobinopathies comprennent la drĂ©panocytose et la bĂȘta-thalassĂ©mie et sont les maladies monogĂ©niques les plus frĂ©quentes dans le monde contrairement Ă  la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale qui est trĂšs rare. La thĂ©rapie gĂ©nique pourrait ĂȘtre une approche thĂ©rapeutique prometteuse pour ces maladies graves. L'Ă©dition du gĂ©nome par CRISPR-Cas9 est revendiquĂ©e comme une alternative Ă  la thĂ©rapie gĂ©nique additive. Nous avons utilisĂ© les coupures doubles brins d’ADN induites par la nuclĂ©ase Cas9 au locus UROS pour Ă©diter la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et au locus bĂȘta-globine pour Ă©diter les bĂȘta-hĂ©moglobinopathies. Nous avons dĂ©montrĂ© qu'aprĂšs une seule coupures double brin d’ADN par CRISPR, les insertions-dĂ©lĂ©tions au site de coupure du locus UROS sur le chromosome 10, pouvaient ĂȘtre concomitantes de grandes dĂ©lĂ©tions chromosomiques inattendues dans des lignĂ©es cellulaires mais aussi dans des cellules primaires dĂ©ficientes pour TP53. Nous avons confirmĂ© ce rĂ©sultat au locus bĂȘta-globine sur le chromosome 11 dans une lignĂ©e cellulaire. De plus, dans les cellules souches hĂ©matopoĂŻĂ©tiques, nous avons dĂ©crit un autre type de gĂ©notoxicitĂ© au locus bĂȘta-globine : des pertes d'hĂ©tĂ©rozygotie copies neutres conduisant Ă  une disomie uniparentale partielle 11p15.5. Ces nouvelles donnĂ©es sont cruciales car les thĂ©rapies gĂ©niques basĂ©es sur CRISPR-Cas9 sont en cours pour les bĂȘta-hĂ©moglobinopathies chez les patients. Au total, ces effets secondaires sont Ă  prendre en compte pour la modĂ©lisation de maladies et pour la thĂ©rapie gĂ©nique. Nos donnĂ©es mettent en Ă©vidence la nĂ©cessitĂ© de contrĂŽler et d'amĂ©liorer la sĂ©curitĂ© de CRISPR-Cas9 et nous avons proposĂ© une alternative Ă  CRISPR-Cas9-nuclĂ©ase grĂące Ă  l'utilisation de la nickase dans une lignĂ©e cellulaire.The objective of this work was to study the genotoxicity of gene therapy by CRISPR (Clustered Regularly Interspaced Palindromic Repeats) -Cas9 (CRISPR Associated protein) and to propose safety in models of inherited red blood cell diseases, congenital erythropoietic porphyria and beta hemoglobinopathies. Beta-hemoglobinopathies include sickle cell disease and beta-thalassemia and are the most common monogenic diseases in the world unlike congenital erythropoietic porphyria, which is very rare. Gene therapy could be a promising therapeutic approach for these severe diseases. CRISPR-Cas9 mediated genome editing is claimed as an alternative to additive gene therapy. We used Cas9 nuclease-induced double-strand break DNA at the UROS locus to edit congenital erythropoietic porphyria and at the beta-globin locus to edit beta-hemoglobinopathies. We demonstrated, that after a single CRISPR-mediated double-strand break DNA, the on-target insertion-deletions at the UROS locus on the chromosome 10 could be concomitant to unexpected chromosomal large deletions in cell lines but also in primary cells deficient for TP53. We confirmed this concern at the beta-globin locus on chromosome 11 in cell line. Moreover, in hematopoietic stem cells, we described another kind of genotoxicity at the beta-globin locus: copy-neutral losses of heterozygosity leading to 11p15.5 partial uniparental disomy. These new data are crucial because CRISPR-Cas9-based gene therapies are just ongoing for beta-hemoglobinopathies in patients. Altogether, these side effects must be taken into account for disease modeling and for gene therapy. Our data highlight the need to control and improve CRISPR-Cas9 safety and we have proposed an alternative to CRISPR-Cas9-nuclease through the use of nickase in cell line

    Sécurisation de la thérapie génique par CRISPR-Cas9 dans les pathologies du globule rouge

    No full text
    The objective of this work was to study the genotoxicity of gene therapy by CRISPR (Clustered Regularly Interspaced Palindromic Repeats) -Cas9 (CRISPR Associated protein) and to propose safety in models of inherited red blood cell diseases, congenital erythropoietic porphyria and beta hemoglobinopathies. Beta-hemoglobinopathies include sickle cell disease and beta-thalassemia and are the most common monogenic diseases in the world unlike congenital erythropoietic porphyria, which is very rare. Gene therapy could be a promising therapeutic approach for these severe diseases. CRISPR-Cas9 mediated genome editing is claimed as an alternative to additive gene therapy. We used Cas9 nuclease-induced double-strand break DNA at the UROS locus to edit congenital erythropoietic porphyria and at the beta-globin locus to edit beta-hemoglobinopathies. We demonstrated, that after a single CRISPR-mediated double-strand break DNA, the on-target insertion-deletions at the UROS locus on the chromosome 10 could be concomitant to unexpected chromosomal large deletions in cell lines but also in primary cells deficient for TP53. We confirmed this concern at the beta-globin locus on chromosome 11 in cell line. Moreover, in hematopoietic stem cells, we described another kind of genotoxicity at the beta-globin locus: copy-neutral losses of heterozygosity leading to 11p15.5 partial uniparental disomy. These new data are crucial because CRISPR-Cas9-based gene therapies are just ongoing for beta-hemoglobinopathies in patients. Altogether, these side effects must be taken into account for disease modeling and for gene therapy. Our data highlight the need to control and improve CRISPR-Cas9 safety and we have proposed an alternative to CRISPR-Cas9-nuclease through the use of nickase in cell line.L’objectif de ce travail a Ă©tĂ© d’étudier la gĂ©notoxicitĂ© de la thĂ©rapie gĂ©nique par CRISPR (Clustered Regularly Interspaced Palindromic Repeats)-Cas9 (CRISPR associated protein) et de proposer une sĂ©curisation dans des modĂšles de maladies hĂ©rĂ©ditaires du GR, la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et les bĂ©ta-hĂ©moglobinopathies. Les bĂȘta-hĂ©moglobinopathies comprennent la drĂ©panocytose et la bĂȘta-thalassĂ©mie et sont les maladies monogĂ©niques les plus frĂ©quentes dans le monde contrairement Ă  la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale qui est trĂšs rare. La thĂ©rapie gĂ©nique pourrait ĂȘtre une approche thĂ©rapeutique prometteuse pour ces maladies graves. L'Ă©dition du gĂ©nome par CRISPR-Cas9 est revendiquĂ©e comme une alternative Ă  la thĂ©rapie gĂ©nique additive. Nous avons utilisĂ© les coupures doubles brins d’ADN induites par la nuclĂ©ase Cas9 au locus UROS pour Ă©diter la porphyrie Ă©rythropoĂŻĂ©tique congĂ©nitale et au locus bĂȘta-globine pour Ă©diter les bĂȘta-hĂ©moglobinopathies. Nous avons dĂ©montrĂ© qu'aprĂšs une seule coupures double brin d’ADN par CRISPR, les insertions-dĂ©lĂ©tions au site de coupure du locus UROS sur le chromosome 10, pouvaient ĂȘtre concomitantes de grandes dĂ©lĂ©tions chromosomiques inattendues dans des lignĂ©es cellulaires mais aussi dans des cellules primaires dĂ©ficientes pour TP53. Nous avons confirmĂ© ce rĂ©sultat au locus bĂȘta-globine sur le chromosome 11 dans une lignĂ©e cellulaire. De plus, dans les cellules souches hĂ©matopoĂŻĂ©tiques, nous avons dĂ©crit un autre type de gĂ©notoxicitĂ© au locus bĂȘta-globine : des pertes d'hĂ©tĂ©rozygotie copies neutres conduisant Ă  une disomie uniparentale partielle 11p15.5. Ces nouvelles donnĂ©es sont cruciales car les thĂ©rapies gĂ©niques basĂ©es sur CRISPR-Cas9 sont en cours pour les bĂȘta-hĂ©moglobinopathies chez les patients. Au total, ces effets secondaires sont Ă  prendre en compte pour la modĂ©lisation de maladies et pour la thĂ©rapie gĂ©nique. Nos donnĂ©es mettent en Ă©vidence la nĂ©cessitĂ© de contrĂŽler et d'amĂ©liorer la sĂ©curitĂ© de CRISPR-Cas9 et nous avons proposĂ© une alternative Ă  CRISPR-Cas9-nuclĂ©ase grĂące Ă  l'utilisation de la nickase dans une lignĂ©e cellulaire
    corecore