Heat Shock Proteins: Cell Protection through Protein Triage

Heat shock proteins (HSPs) are chaperones that catalyze the proper folding of nascent proteins and the refolding of denatured proteins. The ubiquitin-proteasome system is an error-checking system that directs improperly folded proteins for destruction. A coordinated interaction between the HSPs (renaturation) and the proteasome (degradation) must exist to assure protein quality control mechanisms. Although it still remains unknown how the decision of folding vs. degradation is taken, many pieces of evidence demonstrate that HSPs interact directly or indirectly with the proteasome, assuring quite selectively the proteasomal degradation of certain proteins under stress conditions. In this review, we will describe the different data that demonstrate a role for HSP90, HSP70, HSP27, and alpha-B-crystallin in the partitioning of proteins to either one of these pathways, referred as protein triage

ARIA digital anamorphosis : Digital transformation of health and care in airway diseases from research to practice

Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis. It strengthens the ARIA change management strategy in the prevention and management of airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical framework, solutions for practical steps of digital enhancement of care are proposed.Peer reviewe

Severe Asthma Standard-of-Care Background Medication Reduction With Benralizumab: ANDHI in Practice Substudy

Background: The phase IIIb, randomized, parallel-group, placebo-controlled ANDHI double-blind (DB) study extended understanding of the efficacy of benralizumab for patients with severe eosinophilic asthma. Patients from ANDHI DB could join the 56-week ANDHI in Practice (IP) single-arm, open-label extension substudy. Objective: Assess potential for standard-of-care background medication reductions while maintaining asthma control with benralizumab. Methods: Following ANDHI DB completion, eligible adults were enrolled in ANDHI IP. After an 8-week run-in with benralizumab, there were 5 visits to potentially reduce background asthma medications for patients achieving and maintaining protocol-defined asthma control with benralizumab. Main outcome measures for non-oral corticosteroid (OCS)-dependent patients were the proportions with at least 1 background medication reduction (ie, lower inhaled corticosteroid dose, background medication discontinuation) and the number of adapted Global Initiative for Asthma (GINA) step reductions at end of treatment (EOT). Main outcomes for OCS-dependent patients were reductions in daily OCS dosage and proportion achieving OCS dosage of 5 mg or lower at EOT. Results: For non-OCS-dependent patients, 53.3% (n = 208 of 390) achieved at least 1 background medication reduction, increasing to 72.6% (n = 130 of 179) for patients who maintained protocol-defined asthma control at EOT. A total of 41.9% (n = 163 of 389) achieved at least 1 adapted GINA step reduction, increasing to 61.8% (n = 110 of 178) for patients with protocol-defined EOT asthma control. At ANDHI IP baseline, OCS dosages were 5 mg or lower for 40.4% (n = 40 of 99) of OCS-dependent patients. Of OCS-dependent patients, 50.5% (n = 50 of 99) eliminated OCS and 74.7% (n = 74 of 99) achieved dosages of 5 mg or lower at EOT. Conclusions: These findings demonstrate benralizumab's ability to improve asthma control, thereby allowing background medication reduction

ARIA digital anamorphosis: Digital transformation of health and care in airway diseases from research to practice

Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis. It strengthens the ARIA change management strategy in the prevention and management of airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical framework, solutions for practical steps of digital enhancement of care are proposed

A Solve-RD ClinVar-based reanalysis of 1522 index cases from ERN-ITHACA reveals common pitfalls and misinterpretations in exome sequencing

Purpose Within the Solve-RD project (https://solve-rd.eu/), the European Reference Network for Intellectual disability, TeleHealth, Autism and Congenital Anomalies aimed to investigate whether a reanalysis of exomes from unsolved cases based on ClinVar annotations could establish additional diagnoses. We present the results of the “ClinVar low-hanging fruit” reanalysis, reasons for the failure of previous analyses, and lessons learned. Methods Data from the first 3576 exomes (1522 probands and 2054 relatives) collected from European Reference Network for Intellectual disability, TeleHealth, Autism and Congenital Anomalies was reanalyzed by the Solve-RD consortium by evaluating for the presence of single-nucleotide variant, and small insertions and deletions already reported as (likely) pathogenic in ClinVar. Variants were filtered according to frequency, genotype, and mode of inheritance and reinterpreted. Results We identified causal variants in 59 cases (3.9%), 50 of them also raised by other approaches and 9 leading to new diagnoses, highlighting interpretation challenges: variants in genes not known to be involved in human disease at the time of the first analysis, misleading genotypes, or variants undetected by local pipelines (variants in off-target regions, low quality filters, low allelic balance, or high frequency). Conclusion The “ClinVar low-hanging fruit” analysis represents an effective, fast, and easy approach to recover causal variants from exome sequencing data, herewith contributing to the reduction of the diagnostic deadlock

Fibrose pleurale expérimentale (rôle de transforming growth factor (TGF)-b1 et des agents anticancéreux (bléomycine))

Les liens entre fibrose et plèvre sont importants. Outre la pleurodèse, volontairement induite ou non, la plèvre viscérale peut être le siège de fibroses massives responsables de fibrothorax à la morbidité lourde. La région sous-pleurale est aussi le point de départ géographique de la fibrose pulmonaire idiopathique (FPI) sans qu aucun lien n ait été établi jusqu alors entre les deux. Nous avons développé un modèle de fibrose pleurale, sévère et progressive, induite par le transfert du gène de Transforming Growth Factor (TGF)-b1 aux cellules mésothéliales. L accumulation de collage ne au niveau de la plèvre mais aussi dans la région sous-pleurale y est secondaire à une transformation des cellules mésothéliales en myofibroblastes (transformation mésothélio-fibroblastoïde -TMF-). Ces résultats suggèrent l implication du mésothélium pleural non seulement dans la fibrose pleurale mais également dans la FPI. Nous avons également étudié le rôle des nanoparticules de carbone (NPs, -carbon black ou noir de fumée-), particules "ultrafines" de la pollution et de la fumée de cigarette, sur le pouvoir fibrosant de la bléomycine (BL), agent cytotoxique connu pour ses effets secondaires fibrosants sur le poumon humain. Nous avons montré que les NPs n aggravent pas la fibrose pulmonaire induite par la BL alors que la co-administration BL/NPs est nécessaire à l établissement d une fibrose pleurale. Cette fibrose est, comme dans le modèle précédent, progressive et caractérisée par un dépôt de collagène au niveau pleural et sous-pleural. Nos travaux in vitro sur culture primaire de cellules mésothéliales nous ont permis de confirmer le rôle clé de ces cellules dans le processus de fibrogenèse. Ce travail novateur sur la fibrogenèse pleurale peut aboutir à terme à des applications thérapeutiques de la fibrose pleurale voire de la FPI en utilisant les cellules mésothéliales comme cible.Links between pleura and fibrosis are important. Apart from pleurodesis, visceral pleura can be the site of severe fibrosis leading to fibrothorax associated with a high morbidity. Subpleural parenchyma is also the anatomical region of idiopathic pulmonary fibrosis (IPF) initiation although no link has been established between both. We developed a model of severe and progressive pleural fibrosis, induced by adenovirus-mediated gene transfer of Transforming Growth Factor (TGF)-b1 to mesothelial cells. In this model, collagen accumulation within the pleura but also within the subpleural parenchyma is the result of the transformation of mesothelial cells into myofibroblasts (mesothelio-fibroblastoid transformation -MFT-). This suggests the involvement of pleural mesothelium not only in pleural fibrosis but also possibly in IPF. We also studied the role of carbon nanoparticles (CN, carbon black), ultrafine particles found in ambient pollution or cigarette smoke, on fibrosis induced by bleomycin (BL), a cytotoxic agent known for its fibrotic side effects on human lungs. We showed that CN do not worsen BL-induced pulmonary fibrosis whereas BL+CN co-administration is needed to induce pleural fibrosis. This fibrosis is, as in the first model, progressive and characterized by collagen deposition within the pleura and the subpleural parenchyma. Our in vitro work on primary mesothelial cells confirms the key role of these cells in fibrogenesis. This innovative work on pleural fibrogenesis could lead to therapeutic applications for pleural fibrosis and even maybe IPF by using mesothelial cells as target.DIJON-BU Médecine Pharmacie (212312103) / SudocSudocFranceF

Initiation de la fibrose pulmonaire (rôle particulier de la transition mésenchymateuse de la cellule mésothéliale et de la protéine de choc thermique HSP 27)

La fibrose pulmonaire peut être induite par différentes agressions comme certaines chimiothérapies et notamment la bléomycine. Elle est souvent idiopathique (FPI) sans étiologie retrouvée. Cette maladie, qui n a pas de traitement efficace et un pronostic sombre, débute dans les régions sous-pleurales. Elle est caractérisée par la présence de myofibroblastes responsables de la synthèse de la matrice extracellulaire qui va s accumuler de façon disproportionnée. Ce dépôt excessif de collagène conduira à une perte des fonctions mécaniques du poumon et une limitation des échanges gazeux. L origine des myofibroblastes est encore discutée mais une hypothèse récente propose que les cellules épithéliales puissent, sous l influence de Transforming Growth Factor (TGF)-b1, une cytokine majeure du processus fibrosant, se transformer en myofibroblastes par un procédé nommé transition épithélio-mésenchymateuse (EMT). Dans ce travail, nous nous sommes intéressés dans un premier temps au rôle de la plèvre dans l initiation de la FPI en développant un nouveau modèle de fibrose pleurale, puis nous avons étudié l implication de la petite protéine de choc thermique HSP27 dans l EMT. Enfin, nous nous sommes intéressés à la toxicité d un dérivé de la bléomycine, la déglyco-bléomycine. Nous avons montré dans le premier projet que la bléomycine, quelque soit son mode d administration, pouvait, si elle était associée à la présence de nanoparticules de carbone dans l espace pleural (particules présentes dans la fumée de cigarette et dans la pollution), induire une fibrose pleurale progressive. Cette fibrose pleurale ne se limitait pas à une accumulation de collagène au niveau de la plèvre mais se propageait dans les régions sous-pleurales. Cette invasion de la fibrose s expliquait par la capacité des cellules mésothéliales à subir une EMT. Dans une deuxième étude nous avons montré qu HSP27 était fortement surexprimée au niveau de la plèvre et dans le parenchyme pulmonaire lors de la fibrose pulmonaire idiopathique et également dans nos différents modèles animaux de fibrose pulmonaire et pleurale. Nous avons montré in vitro qu HSP27 était aussi fortement surexprimée au cours de l EMT et que sa surexpression seule suffisait à induire une EMT. Au contraire, l inhibition de son expression in vitro bloquait l induction d une l EMT par le TGF-b1 et in vivo empêchait le développement de la fibrose pleurale et la migration des cellules mésothéliales dans le parenchyme pulmonaire. Enfin dans la troisième partie de notre travail, nous avons démontré chez le rongeur que la déglyco-bléomycine, dérivé de la bléomycine, avait le même effet anti-tumoral que cet anticancéreux mais sans sa toxicité pulmonaire fibrosante. Notre travail met en lumière le rôle probable de la plèvre dans l initiation de la fibrose pulmonaire idiopathique. Nous espérons que nos travaux sur HSP27 et sur la déglyco-bléomycine vont pouvoir rapidement déboucher sur des applications thérapeutiques chez l homme.Pulmonary fibrosis could be induced by a number of injuries like chemotherapy (i.e. bleomycin) or could be idiopathic (IPF). This disease has currently no treatment. IPF classically starts in sub-pleural areas and is characterized by the presence of myofibroblasts producing the extracellular matrix that will accumulated into the parenchyma resulting in impaired lung functions and respiratory failure. The origin of the myofibroblasts is still debated but one recent hypothesis suggests that epithelial cells could become myofibroblasts through the epithelial-to-mesenchymal transition (EMT). This process is initiated by Transforming Growth Factor (TGF)-b1 one of the most, if not the most important cytokine involved in fibrotic process. In this work we focused on the role of the pleura in the onset of IPF and developed a new pleural fibrosis model in mice. We studied the implication of the heat shock protein 27 (HSP27) in pulmonary fibrotic processes. We then focused on the pulmonary toxicity of the deglyco-bleomycin a product derived from the anticancerous bleomycin. We demonstrated in the first part of our work that bleomycin was able, in combination with the presence of carbon nanoparticules in the pleural space (found in cigarette s smoke and pollution), to induce a progressive pleural fibrosis. This pleural fibrosis was associated with a progression of the disease within the subpleural area as observed in IPF patients. This invasion within the parenchyma was explained by the fact that mesothelial cells undergo an EMT. In the second part of our work, we showed that HSP27 was overexpressed in the parenchyma and the pleura of IPF patients and also in all our pleural and pulmonary fibrosis models in rodents. Furthermore we established in vitro that HSP27 was also overexpressed during EMT and that its overexpression was sufficient to induce EMT. Additionally HSP27 inhibition blocks TGF-b1 induced EMT in vitro and blocks pleural fibrosis development and mesothelial cells migration within the parenchyma in vivo. In the last project we demonstrated that deglyco-bleomycin had the same anti-tumoral effect than bleomycin in vivo and was devoided from its pulmonary toxicity. This work highlights the potential role of the pleura in initiating IPF and may open fields for the development of new therapeutics by preventing pulmonary fibrosis initiation but also progression.DIJON-BU Doc.électronique (212319901) / SudocSudocFranceF

Transforming growth factor-b1, connective tissue growth factor et fibrose pulmonaire

DIJON-BU Médecine Pharmacie (212312103) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF