Daily Respiratory Research Analysis

Secreted mucins are multimegadalton glycoprotein polymers that share the function of protecting mucosal tissues but diversified for activities in different organs of the body. Structural studies of secreted mucins are complicated by the enormous sizes, flexibility, and complex supramolecular assembly modes of these glycoproteins. The two major respiratory mucins are MUC5AC and MUC5B. Here, we present structures of a large amino-terminal segment of MUC5AC in the form of helical filaments. These filaments differ from filamentous and tubular structures observed previously for the intestinal mucin MUC2 and the partial mucin homolog VWF. Nevertheless, the MUC5AC helical filaments support the proposed mechanism, based on MUC2 and VWF, for how noncovalent interactions between mucin monomers guide disulfide crosslinking to form polymers. The high-resolution MUC5AC structures show how local and limited changes in amino acid sequence can profoundly affect higher-order assembly while preserving the overall folds and polymerization activity of mucin glycoproteins. Differences in supramolecular assembly are likely to be functionally significant considering the divergence of mechanical properties and physiological requirements between respiratory and intestinal mucins. Determining the high-resolution structures of respiratory mucins provides a foundation for understanding the mechanisms by which they clean and protect the lungs. Moreover, the MUC5AC structure enables visualization of the sites of human amino acid sequence variation and disease-associated mutations.

OBJECTIVES: Randomized clinical trials informing clinical practice (e.g., like large, pragmatic, and late-phase trials) should ideally mostly use harmonized outcomes that are important to patients, family members, clinicians, and researchers. Core outcome sets for specific subsets of ICU patients exist, for example, respiratory failure, delirium, and COVID-19, but not for ICU patients in general. Accordingly, we aimed to develop a core outcome set for adult general ICU patients. DESIGN: We developed a core outcome set in Denmark following the Core Outcome Measures in Effectiveness Trials Handbook. We used a modified Delphi consensus process with multiple methods design, including literature review, survey, semi-structured interviews, and discussions with initially five Danish research panels. The core outcome set was internationally validated and revised based on feedback from research panels in all countries. SETTING: There were five Danish research panels and 17 panels in 13 other countries. Interviews and the three-round Delphi survey was conducted in Denmark, followed by validation of the core outcome set across 14 countries in Europe, Australasia, and India. SUBJECTS: Adult ICU survivors, family members, clinicians, and researchers. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We identified 329 published outcomes, of which 50 were included in the 264 participant Delphi survey. In semi-structured interviews of 82, no additional outcomes were added. The first Delphi survey round was completed by 249 (94%) participants, and 202 (82%) contributed to the third and final round. The initial core outcome set comprised six outcomes. International validation involved 217 research panel members and resulted in the final core outcome set comprising survival, free of life support, free of delirium, out of hospital, health-related quality of life, and cognitive function. CONCLUSIONS: We developed and internationally validated a core outcome set with six core outcomes to be used in research, specifically clinical trials involving adult general ICU patients.

BACKGROUND: In idiopathic pulmonary fibrosis (IPF) patients, alveolar architectures are lost and gas transfer function would decline, which cannot be rescued by conventional anti-fibrotic therapy. P63+ lung basal progenitor cells are reported to have potential to repair damaged lung epithelium in animal models, which need further investigation in clinical trials. METHODS: We cloned and expanded P63+ progenitor cells from IPF patients to manufacture cell product REGEND001, which were further characterized by morphology and single-cell transcriptomic analysis. Subsequently, an open-label, dose-escalation autologous progenitor cell transplantation clinical trial was conducted. We treated 12 patients with ascending doses of cells: 0.6x, 1x, 2x and 3.3x10 RESULTS: P63+ basal progenitor cell was safe and tolerated at all doses, with no dose-limiting toxicity or cell therapy-related severe adverse events observed. Patients in three higher dose groups showed significant improvement of lung gas transfer function as well as exercise ability. Resolution of honeycomb lesion was observed in patients of higher dose groups. CONCLUSIONS: REGEND001 has high safety profile and meanwhile encourages further efficacy exploration in IPF patients. FUNDING: National High Level Hospital Clinical Research Funding (2022-PUMCH-B-108), National Key Research and Development Plan (2024YFA1108900, 2024YFA1108500), Jiangsu Province Science and Technology Special Project Funding (BE2023727), National Biopharmaceutical Technology Research Project Funding (NCTIB2023XB01011), Non-profit Central Research Institute Fund of Chinese Academy of Medical Science (2020-PT320-005), and Regend Therapeutics. CLINICAL TRIAL NUMBER: Chinese clinical trial registry: CTR20210349.