84 research outputs found

    Gene Therapy for Cardiomyopathies

    Get PDF
    Heart disease remains the prevalent cause of premature death and accounts for a significant proportion of all hospital admissions. Molecular genetics was integrated quite late in cardiology, but introduced new concepts like sarcolemmopathies, cytoskeletalopathies, and channelopathies useful to better understand the pathophysiology of the development of inherited cardiomyopathies (CMs). As our understanding of the cellular and molecular processes involved in the development and progression of heart disease improved, new therapeutic targets were identified, as were novel approaches such as delivery of genes to replace defective or deficient components and thereby restore structure or function in a diseased heart. We discuss gene addition strategies in the context of monogenic disorders. Moreover, a broader nucleic acid-based modulation of cardiac gene expression for the treatment of cardiac diseases might have larger clinical indications. Inadequate gene delivery remains a potential cause of negative trials. However, progress in innovative formulations and clinically relevant ways of administration should lead to significant progress in the future. Cardiac gene therapy will be integrated into the therapeutic armamentarium for CM and heart failure

    A Scalable Genome-Editing-Based Approach for Mapping Multiprotein Complexes in Human Cells

    Get PDF
    SummaryConventional affinity purification followed by mass spectrometry (AP-MS) analysis is a broadly applicable method used to decipher molecular interaction networks and infer protein function. However, it is sensitive to perturbations induced by ectopically overexpressed target proteins and does not reflect multilevel physiological regulation in response to diverse stimuli. Here, we developed an interface between genome editing and proteomics to isolate native protein complexes produced from their natural genomic contexts. We used CRISPR/Cas9 and TAL effector nucleases (TALENs) to tag endogenous genes and purified several DNA repair and chromatin-modifying holoenzymes to near homogeneity. We uncovered subunits and interactions among well-characterized complexes and report the isolation of MCM8/9, highlighting the efficiency and robustness of the approach. These methods improve and simplify both small- and large-scale explorations of protein interactions as well as the study of biochemical activities and structure-function relationships

    Immunophenotypic Lymphocyte Profiles in Human African Trypanosomiasis

    Get PDF
    Human African trypanosomiasis (HAT) is a deadly vector-born disease caused by an extracellular parasite, the trypanosome. Little is known about the cellular immune responses elicited by this parasite in humans. We used multiparameter flow cytometry to characterize leukocyte immunophenotypes in the blood and cerebrospinal fluid (CSF) of 33 HAT patients and 27 healthy controls identified during a screening campaign in Angola and Gabon. We evaluated the subsets and activation markers of B and T lymphocytes. Patients had a higher percentage of CD19+ B lymphocytes and activated B lymphocytes in the blood than did controls, but lacked activated CD4+ T lymphocytes (CD25+). Patients displayed no increase in the percentage of activated CD8+ T cells (HLA-DR+, CD69+ or CD25+), but memory CD8 T-cell levels (CD8+CD45RA−) were significantly lower in patients than in controls, as were effector CD8 T-cell levels (CD8+CD45RA+CD62L−). No relationship was found between these blood immunophenotypes and disease severity (stage 1 vs 2). However, CD19+ B-cell levels in the CSF increased with disease severity. The patterns of T and B cell activation in HAT patients suggest that immunomodulatory mechanisms may operate during infection. Determinations of CD19+ B-cell levels in the CSF could improve disease staging

    In vitro and in vivo evaluation of a dextran-graft-polybutylmethacrylate copolymer coated on CoCr metallic stent

    Get PDF
    International audienceIntroduction: The major complications of stent implantation are restenosis and late stent thrombosis. PBMA polymers are used for stent coating because of their mechanical properties. We previously synthesized and characterized Dextrangraft-polybutylmethacrylate copolymer (Dex-PBMA) as a potential stent coating. In this study, we evaluated the haemocompatibility and biocompatibility properties of Dex-PBMA in vitro and in vivo.Methods: Here, we investigated: (1) the effectiveness of polymer coating under physiological conditions and its ability to release TacrolimusÂź, (2) the capacity of Dex-PBMA to inhibit Staphylococcus aureus adhesion, (3) the thrombin generation and the human platelet adhesion in static and dynamic conditions, (4) thebiocompatibility properties in vitro on human endothelial colony forming cells (ECFC) and on mesenchymal stem cells (MSC) and in vivo in rat models, and (5) we implanted Dex-PBMA and Dex-PBMA TAC coated stents in neointimal hyperplasia restenosis rabbit model. Results: Dex-PBMA coating efficiently prevented bacterial adhesion and release TacrolimusÂź. Dex-PBMA exhibit haemocompatibility properties under flow and ECFC and MSC compatibility. In vivo, no pathological foreign body reaction was observed neither after intramuscular nor intravascular aortic implantation. After Dex-PBMA and Dex-PBMATAC coated stents 30 days implantation in a restenosis rabbit model, an endothelial cell coverage was observed and the lumenpatency was preserved.Conclusion: Based on our findings, Dex-PBMA exhibited vascular compatibility and can potentially be used as a coating for metallic coronary stents

    Physico-chemical characterization of the interaction of red fluorescent protein — DsRed with silica layers

    Get PDF
    The Discosoma Recombinant Red Fluorescent (DsRed) protein is the latest member of the family of fluorescent proteins. It holds great promise for applications in biotechnology and cell biology. However, before being used for rational engineering, knowledge on the underlying mechanisms relating the DsRed structural stability and adsorption properties on solid surfaces is highly demanded. The physico-chemical analysis performed in this study reveals that the interaction of DsRed with SiO2 surfaces does not lead to protein denaturation. The secondary structure of DsRed is preserved after adsorption and dehydration. The measured contact angles of sessile droplets with different DsRed concentrations determine the interaction as hydrophilic one. The photoluminescence emission of dehydrated DsRed droplets is found to be slightly red-shifted, peaking at 590 nm

    Detection of the conformational changes of Discosoma red fluorescent proteins adhered on silver nanoparticles-based nanocomposites via surface-enhanced Raman scattering

    Get PDF
    Description of the relationship between protein structure and function remains a primary focus in molecular biology, biochemistry, protein engineering and bioelectronics. Moreover, the investigation of the protein conformational changes after adhesion and dehydration is of importance to tackle problems related to the interaction of proteins with solid surfaces. In this paper the conformational changes of wild-type Discosoma recombinant red fluorescent proteins (DsRed) adhered on silver nanoparticles (AgNPs)-based nanocomposites are explored via surface-enhanced Raman scattering (SERS). Originality in the present approach is to work on dehydrated DsRed thin protein layers in link with natural conditions during drying. To enable the SERS effect, plasmonic substrates consisting of a single layer of AgNPs encapsulated by an ultra-thin silica cover layer were elaborated by plasma process. The achieved enhancement of the electromagnetic field in the vicinity of the AgNPs is as high as 105. This very strong enhancement factor allowed detecting Raman signals from discontinuous layers of DsRed issued from solution with protein concentration of only 80 nM. Three different conformations of the DsRed proteins after adhesion and dehydration on the plasmonic substrates were identified. It was found that the DsRed chromophore structure of the adsorbed proteins undergoes optically assisted chemical transformations when interacting with the optical beam, which leads to reversible transitions between the three different conformations. The proposed time-evolution scenario endorses the dynamical character of the relationship between protein structure and function. It also confirms that the conformational changes of proteins with strong internal coherence, like DsRed proteins, are reversibl

    Exploring the complementarity of pancreatic ductal adenocarcinoma preclinical models

    Get PDF
    Purpose: Compare pancreatic ductal adenocarcinoma (PDAC), preclinical models, by their transcriptome and drug response landscapes to evaluate their complementarity. Experimental De-sign: Three paired PDAC preclinical models—patient‐derived xenografts (PDX), xenograft‐derived pancreatic organoids (XDPO) and xenograft‐derived primary cell cultures (XDPCC)—were derived from 20 patients and analyzed at the transcriptomic and chemosensitivity level. Transcriptomic characterization was performed using the basal‐like/classical subtyping and the PDAC molecular gradient (PAMG). Chemosensitivity for gemcitabine, irinotecan, 5‐fluorouracil and oxaliplatin was established and the associated biological pathways were determined using independent component analysis (ICA) on the transcriptome of each model. The selection criteria used to identify the different components was the chemosensitivity score (CSS) found for each drug in each model. Results: PDX was the most dispersed model whereas XDPO and XDPCC were mainly classical and basal-like, respectively. Chemosensitivity scoring determines that PDX and XDPO display a positive correlation for three out of four drugs tested, whereas PDX and XDPCC did not correlate. No match was observed for each tumor chemosensitivity in the different models. Finally, pathway analysis shows a significant association between PDX and XDPO for the chemosensitivity‐associated pathways and PDX and XDPCC for the chemoresistance‐associated pathways. Conclusions: Each PDAC preclinical model possesses a unique basal‐like/classical transcriptomic phenotype that strongly in-fluences their global chemosensitivity. Each preclinical model is imperfect but complementary, sug-gesting that a more representative approach of the clinical reality could be obtained by combining them. Translational Relevance: The identification of molecular signatures that underpin drug sensitivity to chemotherapy in PDAC remains clinically challenging. Importantly, the vast majority of studies using preclinical in vivo and in vitro models fail when transferred to patients in a clinical setting despite initially promising results. This study presents for the first time a comparison between three preclinical models directly derived from the same patients. We show that their applica-bility to preclinical studies should be considered with a complementary focus, avoiding tumor-based direct extrapolations, which might generate misleading conclusions and consequently the overlook of clinically relevant features.Fil: Hoare, Owen. Centre National de la Recherche Scientifique; FranciaFil: Fraunhoffer Navarro, Nicolas Alejandro. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Centro de Estudios FarmacolĂłgicos y BotĂĄnicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios FarmacolĂłgicos y BotĂĄnicos; ArgentinaFil: Elkaoutari, Abdessamad. Centre National de la Recherche Scientifique; FranciaFil: Gayet, Odile. Centre National de la Recherche Scientifique; FranciaFil: Bigonnet, Martin. Centre National de la Recherche Scientifique; FranciaFil: Roques, Julie. Centre National de la Recherche Scientifique; FranciaFil: Nicolle, RĂ©my. No especifĂ­ca;Fil: McGuckin, Colin. Cell Therapy Research Institute; FranciaFil: Forraz, Nico. Cell Therapy Research Institute; FranciaFil: Sohier, Emilie. Le Centre RĂ©gional de Lutte Contre Le Cancer LĂ©on BĂ©rard; FranciaFil: Tonon, Laurie. Le Centre RĂ©gional de Lutte Contre Le Cancer LĂ©on BĂ©rard; FranciaFil: Wajda, Pauline. Le Centre RĂ©gional de Lutte Contre Le Cancer LĂ©on BĂ©rard; FranciaFil: Boyault, Sandrine. Le Centre RĂ©gional de Lutte Contre Le Cancer LĂ©on BĂ©rard; FranciaFil: Attignon, ValĂ©ry. Le Centre RĂ©gional de Lutte Contre Le Cancer LĂ©on BĂ©rard; FranciaFil: Tabone, Luciana Belen. Le Centre RĂ©gional de Lutte Contre Le Cancer LĂ©on BĂ©rard; FranciaFil: Barbier, Sandrine. No especifĂ­ca;Fil: Mignard, Caroline. No especifĂ­ca;Fil: Duchamp, Olivier. No especifĂ­ca;Fil: Iovanna, Juan. Centre National de la Recherche Scientifique; FranciaFil: Dusetti, Nelson J.. Centre National de la Recherche Scientifique; Franci

    Establishing a large prospective clinical cohort in people with head and neck cancer as a biomedical resource: head and neck 5000

    Get PDF
    BACKGROUND: Head and neck cancer is an important cause of ill health. Survival appears to be improving but the reasons for this are unclear. They could include evolving aetiology, modifications in care, improvements in treatment or changes in lifestyle behaviour. Observational studies are required to explore survival trends and identify outcome predictors. METHODS: We are identifying people with a new diagnosis of head and neck cancer. We obtain consent that includes agreement to collect longitudinal data, store samples and record linkage. Prior to treatment we give participants three questionnaires on health and lifestyle, quality of life and sexual history. We collect blood and saliva samples, complete a clinical data capture form and request a formalin fixed tissue sample. At four and twelve months we complete further data capture forms and send participants further quality of life questionnaires. DISCUSSION: This large clinical cohort of people with head and neck cancer brings together clinical data, patient-reported outcomes and biological samples in a single co-ordinated resource for translational and prognostic research
    • 

    corecore