Journal of Cystic Fibrosis

BackgroundCystic Fibrosis (CF) is a lethal genetic condition affecting over 100,000 people worldwide, characterised by multi-organ dysfunction and a progressive lethal lung disease. The disease occurs due to faulty cystic fibrosis transmembrane conductance regulator (CFTR) ion channels effecting flow of chloride, bicarbonate and water out of cells. This causes thick mucus with repeated bacterial infections, systemic inflammation and a decrease in lung function. CFTR modulator therapies have shown variable improvements in lung function and reduction in exacerbation frequency. Basal cells within the lung act as a stem cell for repair following injury and can repopulate the epithelial layer. This process is dysfunctional in CF causing progressive damage. Spontaneous lung repair is well described but not well characterised. Nothing is known about the effects of CFTR modulator therapy on these cells, but this could be of major consequence for people with CF (pwCF). AimsTo determine the effects of CFTR modulator therapy on the activity of CF basal cells and relate this to progenitor function and to study the effects of CFTR modulators on systemic inflammation and clinical outcomes. MethodsClinical information, blood and nasal brushes were obtained from pwCF prior to commencing modulator therapy and at multiple time points up until 1 year of treatment. 10 pwCF were recruited to undertake thoracic CT scans pre-treatment and at 1 year of therapy. Nasal samples were used to isolate basal cells and serum to study systemic markers of inflammation. RNA sequencing of basal cells was undertaken by Ilumina Novoseq to a depth of 20 million read pairs and gene ontology analysis was performed. Functional assays of basal cell activity were carried out. Proteomic analysis and ELISAs were undertaken to determine changes in inflammatory cytokines within the serum across the first year of treatment. Quantitative results were generated by Lung Quantification (LungQ) analysis with qualitative reports from independent radiologists. Results were compared with clinical outcomes. Results110 pwCF were recruited in total who commenced a commercially available CFTR modulator therapy. Serum samples were collected from 77pwCF, nasal brushes obtained from 40 pwCF and 10 completed their CT scans following 1 year of highly effective CFTR modulator therapy. Systemic IL-6, CRP and calprotectin (a biomarker of CF exacerbation) were all significantly reduced with highly effective CFTR modulator treatment. Clinical results were in keeping with those seen in published CFTR modulator clinical trials with improvement in lung function, weight, and exacerbation frequency. Subjective improvements were seen in all 10 CT scans following 1 year of modulator therapy. Significant reductions were seen in airway wall thickening and reduction in thoracic lymphadenopathy were also observed. Basal cell RNA sequencing showed that the relative expression of 2570 genes were significantly different following treatment with CFTR modulators. Ontology analysis showed enrichment in multiple pathways including cilliagenesis and Notch signalling, a key pathway in lung tissue development and homeostasis. Functional assays exhibited a deficit in repair mechanisms of the CF basal cell compared to healthy controls, and reduction in progenitor function. ConclusionsAlthough CFTR modulators improve multiple clinical and radiological outcomes, they also have impacts on basal cell function. There are however, limited impacts on systemic inflammation and more work is needed in this area to understand the disease process.

CFTR modulator therapies have transformed CF care, yet chronic airway inflammation persists in many people with cystic fibrosis (pwCF) even after long-term highly effective modulator therapy (HEMT). Because of the adverse side effects or the incompatibility with CFTR modulators, the use of traditional anti-inflammatory therapies is very limited in CF. Hence, new therapeutic strategies that rebalance inflammation without worsening infection with immunosuppression are needed. We evaluated the selective phosphodiesterase 4 (PDE4) inhibitor apremilast (Apr) for its ability to modulate dysregulated inflammation in humanized CF (G551D) rats acutely challenged with Pseudomonas aeruginosa. Apr is an approved anti-inflammatory therapeutic strategy for several chronic inflammatory conditions, but it has not been well studied in CF. In the humanized CF (G551D) rats, a short prophylactic Apr regimen significantly preserved lung function and reduced lung injury, accompanied by broad modulation of inflammatory responses, notably within Th1 and Th17 axes. Importantly, Apr did not cause a significant increase in bacterial burden. Just as importantly, Apr did not reduce CFTR mRNA or protein in vivo, and it increased G551D-CFTR phosphorylation critical for channel gating in vitro, supporting mechanistic compatibility with HEMT. These findings suggest Apr as a potential adjunct to CFTR modulators to rebalance airway inflammation while preserving host defense.

Staphylococcus aureus is the most common bacterial pathogen affecting pediatric patients with Cystic fibrosis (CF), a genetic disorder that causes thick mucus buildup in the lungs, providing a scaffold for chronic infections. Antibiotic treatment is typically guided by standard in vitro antimicrobial susceptibility testing (AST) in Mueller-Hinton broth (MHB), which does not represent the infection site in CF lungs. Notably, discordances between AST predictions and antibiotic therapeutic outcomes were reported in up to 50% of CF cases. To address this gap, we conducted ASTs against methicillin-resistant S. aureus (MRSA) in CF sputum-mimetic media compared with MHB, demonstrating [≥]4-fold discordances across four of nine antibiotic classes. Most significantly, we observed unexpected {beta}-lactam sensitization of MRSA strains (up to 128-fold) in CF sputum-like media, crossing the CLSI clinical breakpoint, suggesting this shift may alter therapeutic outcomes. Genome-wide screens and follow-up assays revealed underlying cell envelope remodelling and alterations to cell envelope stress responses. On the other hand, mucin binding to daptomycin may have led to an apparent 8-fold increase in resistance to this antibiotic in one of the CF sputum-like media. Overall, our AST results in CF sputum-mimetic conditions provide insights into bacterial responses during CF infections. Importantly, they suggest {beta}-lactams may be effective in treating MRSA infections in CF patients, warranting further investigation in relevant in vivo systems.

BackgroundBronchiectasis in adults often goes undiagnosed following the routine assessment. Cystic Fibrosis (CF) is usually diagnosed during childhood, but some cases are identified in adulthood when disease is mild. High-resolution computed tomography (HRCT) of chest may offer structural information that can indicate CF as an underlying etiology. ObjectiveTo compare the HRCT features of adult patients with CF and non-CF bronchiectasis and to determine the radiologic features that may be suggestive of CF. MethodsThis retrospective, analytical, cross-sectional study was carried out in Bangladesh Medical University after IRB clearance. Total 130 adults (12 with CF and 118 with non-CF bronchiectasis) of both sexes, whose bronchiectasis was confirmed by chest HRCT were included. Imaging findings were assessed based on Reid morphological classification, anatomical distribution and extent of spread within the lungs, and their association was tested using chi-square test with statistical significance of p<0.05. ResultsCystic bronchiectasis was more common in CF than non-CF patients (83.3% vs 29.7; p<0.001). Mixed central-peripheral extension had been found a considerable associated with CF (66.7% vs. 42.4; p=0.034). There was no statistically significant difference in right lung lobar distribution (p=0.540) but combined upper and lower lobe involvement on the left side was more common in CF patients (54.5%) than non-CF patients (21.3) (p=0.054). ConclusionAdult CF had unique chest HRCT imaging characteristics when compared to non-CF bronchiectasis, especially cystic morphology and mixed extension. Identification of such features could help physician in the early diagnosis and selection of treatment strategy.

Pseudomonas aeruginosa infections in adults with cystic fibrosis (CF) are comprised of heterogeneous populations, most often tracing ancestry back to a single recent common ancestor. What is not clear is the physical spatial structure within the lung infection population, its stability over time and whether this physical structure leads to different evolutionary trajectories in different adaptive environments. To compare the P. aeruginosa populations across a single lung, we performed whole genome sequence analyses of 450 isolates recovered from lavage samples of the three different lobes of the right lung from a person with mild-to-moderate CF lung disease at three time points over the course of [~]1.5 years. We found that isolates fell into five distinct phylogenetic lineages with evidence for repeated translocation of isolates from different lineages across lobes and loss-of-function mutations in lasR and mucA were present in all 450 isolates. The well-resolved phylogenetic analyses revealed a structured population in which we find the coexistence of a slowly evolving lineage and more rapidly evolving lineages. There is also support for numerous migration events. Further, strong evidence for parallel adaptive mutations in multiple genes revealed distinct evolutionary paths affecting mucoid phenotypes and genetic variation in antibiotic resistance-associated pathways across coexisting populations within a single individual over time. These results provide an example of within-host evolution leading to microheterogeneity that may be useful to consider in future study of infection metapopulations dynamics over the course of chronic infection. IMPORTANCEIndividuals with cystic fibrosis (CF) commonly have chronic lung infections that contain clonally derived Pseudomonas aeruginosa populations with genotypic and phenotypic diversity. This study describes a substantial dataset containing 450 isolates from different lobes of the right lung across three timepoints from an individual with mild-to-moderate CF lung disease. Some regional enrichment for specific lineages with parallel mutations among individual lobes of the lung was observed, but longitudinal analysis also demonstrated that compartmentalization is not strictly maintained and that isolates migrate between lobes of the lung over time. Perspectives on within lung evolution will be important for understanding the pathogen populations in chronic respiratory infections in CF and other diseases.

Polymicrobial lung infections are common in individuals with cystic fibrosis (CF). Pathogen communities typically follow an ecological succession in which early colonizers such as Haemophilus influenzae and Staphylococcus aureus are later joined by Pseudomonas aeruginosa. Although adaptation to the lung environment is well described for single pathogens in adult people with CF, much less is known about the role of pathogen interactions and how changes in individual pathogens influence community dynamics at the early stages of disease. To address these questions, we combined genome sequencing with phenotypic screens and pathogen interaction assays using longitudinal clinical isolates (19 P. aeruginosa, 44 S. aureus, and 21 H. influenzae) collected from 23 children with CF (0-7.9 years of age) enrolled in the SCILD (Swiss CF Infant Lung Development) cohort. Our analysis revealed that early pathogen communities are characterized by a combination of strain turnover and persistence of isolates undergoing first steps of within-host evolution. Most notably, quorum-sensing-deficient P. aeruginosa variants repeatedly emerged, showing reduced protease production and diminished inhibition of S. aureus and H. influenzae. These changes indicate that P. aeruginosa becomes less antagonistic towards co-occurring pathogens, possibly promoting community stability. Together, our results show that ecological and evolutionary dynamics between pathobiome members may play an underappreciated role in shaping CF lung disease during early childhood.

BackgroundImpulse oscillometry is a noninvasive pulmonary function test performed during quiet breathing and requires minimal patient cooperation. It is useful for detecting small airway disease and provides increased sensitivity for diagnosing asthma in younger children who may have difficulty completing standard spirometry. Bronchodilator testing, a standard assessment of airflow obstruction reversibility, is recommended in patients with suspected asthma who present obstructive airflow patterns. ObjectiveTo evaluate impulse oscillometry parameters before and after bronchodilator administration across different age groups and to examine the relationship between age and airway resistance in patients with clinician-diagnosed asthma. MethodsThis retrospective study included patients with clinician-diagnosed asthma who demonstrated obstructive airflow patterns and a positive bronchodilator response. Participants were grouped by age: younger than 6 years, 6 to 20 years, and older than 20 years. Key impulse oscillometry parameters--airway resistance at 5 Hz, airway resistance at 20 Hz, the difference between these values, and resonance frequency--were collected and compared across groups. A positive bronchodilator response was defined as a reduction in airway resistance of more than 30% in individuals younger than 18 years and more than 40% in adults. ResultsA total of 225 patients (123 males and 102 females) were included, with a median age of 6 years. At baseline, the median airway resistance at 5 Hz was 175.34% of the reference value (95% CI, 171.66-178.62), and airway resistance at 20 Hz was 121.68% (95% CI, 118.73-127.12). The median difference between these values was 52.32% (95% CI, 49.89-57.14), and the median resonance frequency was 5.11 Hz (95% CI, 4.62-5.35). After bronchodilator administration, airway resistance at 5 Hz decreased to 123.56% (95% CI, 119.07-126.77), corresponding to a median reduction of 52.8% (95% CI, 49.48-56.08; P < 0.0001). Age demonstrated a moderate positive correlation with airway resistance at 20 Hz (r = 0.51, P < 0.001). ConclusionsProximal airway resistance increases with age among patients with asthma, suggesting age-related differences in airway inflammation. Impulse oscillometry combined with bronchodilator assessment provides a practical approach for evaluating airflow reversibility and enhances diagnostic accuracy in suspected asthma.

BackgroundIdiopathic pulmonary fibrosis (IPF) remains a fatal interstitial lung disease with limited diagnostic specificity and therapeutic options. This study integrates bulk and single-cell RNA sequencing (RNA-seq) to identify novel biomarkers and elucidate molecular mechanisms underlying IPF pathogenesis. MethodsWe prospectively enrolled 14 treatment-naive IPF patients and 6 controls. Bulk RNA-seq was performed on bronchoalveolar lavage fluid (BALF), while single-cell RNA-seq analyzed lung tissues from 4 IPF patients and 3 controls. Differentially expressed genes (DEGs) were identified (|log2FC| >1, FDR <0.05), followed by functional enrichment, protein-protein interaction (PPI) network analysis, and cell-type-specific expression profiling. Results1. DEG Identification: Bulk RNA-seq revealed 108 DEGs (24 upregulated, 84 downregulated). KEGG enrichment analysis of DEGs revealed that upregulated genes were mainly enriched in inflammation and immune pathways (such as NF-{kappa}B signaling pathway, Fc epsilon RI signaling pathway, B cell receptor signaling pathway, phagosome, Fc gamma R-mediated phagocytosis), pyrimidine metabolism, cell cycle, and PI3K-Akt signaling pathway. 2. PPI Network: Module analysis identified a proliferative gene module 1 (NUF2, CEP55, ANLN, TTK, TK1, MYBL2, CCNA2, RRM2, CDT1) linked to cell division and cycle regulation. 3. Single-Cell Insights: scRNA-seq of 30,477 cells delineated 11 populations. Module 1 genes exhibited predominant expression in proliferating cells, Module 1 signature score of proliferating cells was significantly higher in IPF than in control group. 4. Pathogenic Links: Key genes (e.g., CEP55, TTK) were associated with PI3K/AKT signaling, epithelial-mesenchymal transition (EMT), and anti-apoptotic pathways, mirroring oncogenic mechanisms. ConclusionThis multi-omics approach uncovers a proliferation-centric gene module in IPF, revealing shared molecular pathways with tumorigenesis. Our findings highlight novel diagnostic biomarkers and suggest repurposing cell cycle inhibitors as potential therapies. Future studies should validate these targets in preclinical models to advance precision medicine for IPF.

Splice site mutations represent a major class of pathogenic mutations in many diseases, as these changes disrupt normal splicing leading to gene expression changes. Cystic fibrosis (CF) results from mutations to the cystic fibrosis transmembrane conductance regulator (CFTR) gene that encodes an essential ion channel. Approximately 13% of the over 2,100 known CFTR mutations disrupt 3 or 5 splice sites and are predicted to cause splicing defects. Because each splicing mutation is rare, developing individualized therapies to treat each one is financially challenging. Exon specific U1 snRNA (ExSpeU1) targets the non-conserved intronic region downstream the 5 splice site (ss) to rescue exon skipping. Because this approach is exon-rather than mutation-specific, a single agent can potentially rescue multiple mutations. In this study, we have developed a platform to systematically classify all patient variants associated with an exon that are predicted to affect splicing and then determine their rescue potential using ExSpeU1. Here we report the results of these studies. Our minigene reporter study shows that 7 of 10 exon 18 variants resulted in exon skipping. Four mutations at the 3 and 5 ss were rescued at least partially using a single ExSpeU1. Using a luciferase reporter, we observe that the splicing rescue is reflected at the protein level. Lastly, we demonstrate exon-targeting ExSpeU1s can also rescue 3 and 5 ss mutations. Overall, this study exemplifies the power of our platform to screen and rescue multiple patient-derived splicing mutations using a single agent.

Chronic antibiotic-resistant cystic fibrosis (CF) lung infections are the leading cause of death in adults with CF. Despite advances in highly effective modulator therapies, microbial communities persist in the CF lung. The pathogenesis of CF airway infections can be exacerbated by pathogens such as Pseudomonas aeruginosa, which communicates with primary human bronchial epithelial cells (pHBEC) by secreting bacterial extracellular vesicles (bEVs) that diffuse through mucus and deliver virulence factors, DNA, and RNA to pHBEC. However, most CF lung infections are polymicrobial in nature, and therefore, the contribution of polymicrobial bEVs remains to be determined. By using a polymicrobial culture model representing a pulmotype detected in [~]34% of lung infections in people with CF (pwCF), comprised of P. aeruginosa, Staphylococcus aureus, Streptococcus sanguinis, and Prevotella melaninogenica grown in synthetic sputum medium under anoxia, we report that each bacterial genus in the polymicrobial community secretes bEVs containing proteins and RNAs predicted to promote the establishment of chronic infection by enhancing virulence, biofilm formation, and upregulating the stress response and pro-inflammatory pathways in pHBEC. This response is most pronounced in CF pHBEC. Elexacaftor/Tezacaftor/Ivacaftor (ETI), a highly effective modulator therapy, does not ameliorate the response or return it to WT levels. Bacterial EVs also inhibited ETI CFTR Cl- currents by CF pHBEC. These studies provide insight into why ETI does not eliminate polymicrobial lung infections and a hyperinflammatory lung environment in pwCF. IMPORTANCECystic fibrosis (CF) is a genetic disease characterized by chronic polymicrobial lung infections that, if untreated, are one of the primary causes of death in CF. Elexacaftor/Tezacaftor/Ivacaftor (ETI) has many positive clinical outcomes, but it does not eliminate chronic polymicrobial lung infections or inflammation. Using a new biologically relevant co-culture model, we have demonstrated that bacteria secrete vesicles (bEVs) that contain proteins and RNAs. We observed that these RNA-loaded bEVs are predicted to promote the pathogenesis of chronic CF lung infections by enhancing bacterial virulence and biofilm formation, as well as upregulating the pro-inflammatory response in lung cells. ETI does not ameliorate the response of lung cells to bEVs. Our research will facilitate the development of more effective approaches to eliminate infection and inflammation in CF and other lung diseases characterized by chronic polymicrobial infections and excessive inflammation.

Background and AimMASLD affects 30-38% of Indian adults, yet the contribution of genetic risk variants to disease susceptibility and fibrosis progression remains poorly characterised. We investigated the association of 12 candidate SNPs with MASLD susceptibility and fibrosis severity in North Indian patients, benchmarking allele frequencies against IndiGenomes and global populations. MethodsSixty-nine MASLD patients (75.4% male; median BMI 29.8 kg/m{superscript 2}) from a tertiary care liver clinic in New Delhi were genotyped for 12 SNPs using Illumina custom BeadChip array and Sanger sequencing. Patients were stratified by liver stiffness measurement (LSM): significant fibrosis ([&ge;]8 kPa, n=38) versus no significant fibrosis (<8 kPa, n=31). Allele frequencies were compared with IndiGenomes ([~]1,020 Indian individuals) and 1000 Genomes populations. ResultsPNPLA3 rs738409 G allele was the strongest within-cohort predictor of significant fibrosis (allelic OR 2.89, 95% CI 1.35-6.19, P=0.006; dominant model OR 3.94, P=0.008), with carriers demonstrating higher LSM (median 15.6 vs. 7.5 kPa, P=0.005). SAMM50 rs3761472 (OR 2.12, P=0.065) and FTO rs9939609 (OR 2.08, P=0.089) showed non-significant trends. In the population-level comparison, APOC3 rs2854116 T allele was the only variant significantly enriched after Bonferroni correction (64.0% vs. 47.9%; OR 1.93, 95% CI 1.35-2.77, P<0.001), followed by PNPLA3 (33.3% vs. 24.1%, OR 1.57, P=0.019) and SAMM50 (31.2% vs. 22.6%, OR 1.55, P=0.028). Notably, APOC3 showed no association with fibrosis (OR 0.96, P=1.000), suggesting a role in susceptibility rather than progression. All SNPs were in Hardy-Weinberg equilibrium. ConclusionsThis study reveals a dissociation between genetic determinants of MASLD susceptibility and fibrosis progression in North Indian patients. APOC3 rs2854116 predisposes to MASLD at the population level, while PNPLA3 rs738409 drives fibrosis severity within established disease, underscoring the need for ancestry-specific genetic risk stratification. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/26347059v1_ufig1.gif" ALT="Figure 1"> View larger version (69K): org.highwire.dtl.DTLVardef@a07808org.highwire.dtl.DTLVardef@12882adorg.highwire.dtl.DTLVardef@9b33a1org.highwire.dtl.DTLVardef@15aa5e8_HPS_FORMAT_FIGEXP M_FIG C_FIG

Mucociliary clearance is a key component of the pathophysiology of bronchiectasis but cilia function is poorly defined. This study aims to characterize nasal ciliary function in bronchiectasis and examine associations with disease severity, infection, inflammation and outcome. Adults with bronchiectasis and healthy volunteers were recruited to the international observational study EMBARC-BRIDGE. Individuals with a known diagnosis of Primary Ciliary Dyskinesia (PCD) were excluded. Nasal respiratory epithelium was sampled by brush biopsy. Ciliary function was assessed by high-speed video microscopy in primary samples and following re-differentiation in air-liquid interface (ALI) culture. Ciliary parameters (cilia length, angle, amplitude, clearance, frequency and ciliation) were quantified and compared with disease severity, microbiology, inflammation and future risk of exacerbations. 171 participants with bronchiectasis were recruited (54% female, age 68years (59-74)). Bronchiectasis nasal brushings showed greater epithelial disruption compared to healthy volunteers (p=0.0006). Six individuals with previously undiagnosed PCD were identified and excluded. In the remaining bronchiectasis cohort, ciliary beat frequency and length were similar to healthy controls. In contrast ciliary beat amplitude, angle, amplitude per second and clearance capacity, were significantly reduced (all p<0.001). These parameters were restored following ALI culture. Regenerated epithelia from bronchiectasis donors exhibited reduced ciliated area. Ciliary dysfunction was strongly associated with future risk of severe exacerbations. The upper airway epithelium is disrupted in bronchiectasis; ciliary movement is impaired and is associated with future risk of exacerbation. Ciliary dysmotility is reversible following ALI culture. This indicates that impaired ciliary function is secondary to the airway environment and therapeutically targetable.

AimThe mammalian tracheal epithelium is composed by different cell types unevenly distributed along the proximal-distal axis. Nevertheless, variations in expression and function of ion channels and transporters participating in fluid absorption and secretion had never been studied separately in proximal and distal sections of the mouse trachea. In this work, we aim to characterize basal and stimulated absorption and secretion of fluid obtained from proximal and distal trachea from the same animal. MethodsUssing chamber experiments were performed using a custom-made tissue slider that allowed the mounting small tracheal sections, where response to agonists and blockers was recorded. The role of the NKCC1 co-transporter was studied using the Slc12a2-/- mouse. A genetically tomato-induced mouse model was used to assess co-expression of NKCC1 and ASCL3 by immunofluorescence. Animals were instilled with different interleukins (ILs) to determine changes in absorption, secretion and mucus properties. ResultsProximal trachea didnt participate in sodium absorption but exhibited higher cAMP- and succinate-induced anion secretion than the distal section. NBCe1-dependent bicarbonate and TMEM16A-driven chloride secretion was significantly higher in the distal section. NKCC1+ cells were found in the submucosal glands (SMGs) and abundant patches of NKCC1+ cells in the distal region. Isolated NKCC1+ cells co-expressing ASCL3 were also detected. ILs treatment changed the electrophysiological properties of the distal but not the proximal trachea. ConclusionsOur experiments determined that the mouse trachea organizes its functions differentially in the proximal and distal sections, based in the functional distribution of channels, transporters and receptors. While the distal trachea drastically changed its responses to agonists inducing anion secretion the proximal trachea was unperturbed by the action of ILs.

Background and AimsThe prognosis of interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis (IPF) has not been studied as extensively as IPF. This study aimed to evaluate baseline factors associated with mortality in non-IPF ILD, including demographic characteristics, respiratory function test (RFT), comorbidities, and ILD subtypes. MethodsThis retrospective cohort study analysed prospectively collected data of patients with non-IPF ILD at a single tertiary centre in Malaysia (2010-2023). Patients without baseline RFT or HRCT were excluded. Survival was assessed using Kaplan-Meier analysis, and mortality predictors were identified using Cox regression. ResultsThe mean age was 60 {+/-} 15 years, with a male-to-female ratio of 1:3. Indian ethnicity constituted the largest group (n = 109, 47.6%). The mean baseline forced vital capacity (FVC) was 53.3 {+/-} 21% predicted. An FVC <50% predicted, age [&ge;]50 years at diagnosis, specific ILD subtypes, and ethnicity were independently associated with mortality. Compared with Malays, both Chinese (hazard ratio [HR] 9.86, 95% confidence interval [CI] 1.27-76.89, p = 0.037) and Indians (HR 8.59, 95% CI 1.14-64.69, p = 0.001) were associated with a higher risk of death. Kaplan-Meier analysis demonstrated significant differences in survival across non-IPF ILD subtypes (log-rank p = 0.048), with hypersensitivity pneumonitis showing the poorest prognosis (mean survival 6.1 years). ConclusionEthnicity emerged as an independent prognostic factor for mortality in non-IPF ILD. The underlying mechanisms remain unclear and may reflect differences in genetic variation, cultural factors, or environmental exposures. Larger prospective studies are required to validate these findings.

IntroductionFibrosis can affect organs throughout the body and is present in a wide range of diseases. Recent research has suggested that there could be shared biological mechanisms that lead to fibrosis in different organs. MethodsWe performed genome-wide association studies using UK Biobank for fibrosis in 12 different organ-systems and meta-analysed results with previously published studies of fibrotic diseases. We considered genetic associations that colocalised across [&ge;]3 organs as those likely to be involved in general fibrotic mechanisms and also identified novel genetic variants not previously reported as associated with fibrosis. Genetic correlation of fibrosis between organs was calculated using linkage disequilibrium score regression (LDSC). Discovery analyses were performed using European ancestry individuals and results were tested further in African, South Asian and East Asian ancestry groups. ResultsWe identified eight genetic loci that colocalised across three or more organs. One of these signals, located near the SH2B3 and ATXN2 genes, showed evidence of a shared causal variant for fibrosis across five organs. We also identified two novel fibrotic associations, one implicating alternative splicing of TFCP2L1 for urinary fibrosis and another implicating a missense variant in FAM180A for intestinal-pancreatic fibrosis. We observed significant genetic correlations for all organs, particularly for liver and skeletal fibrosis. ConclusionWe found evidence of shared genetic associations for fibrosis across organs, both at individual genetic loci and genome-wide. This highlights specific genes that may contribute to fibrosis across organs and diseases, which may facilitate the development of new therapies.

BackgroundThe extracellular matrix (ECM) is a dynamic network that provides structural support and maintains tissue homeostasis. Collagens are the main structural components of the ECM, occupying distinct tissue compartments and serving specialized roles. Dysregulated ECM remodeling involves an imbalance between collagen production and degradation, generating neoepitope-specific fragments that can be released into circulation. Serological measurements of these fragments can be used as biomarkers of disease and have been associated with progression and mortality in different fibrotic diseases, including pulmonary fibrosis (PF). This study aimed to investigate whether these systemic biomarkers originate from human lung tissue in patients with PF and non-fibrotic controls. MethodsLung tissue was collected from patients with PF (n = 21) and non-fibrotic controls (n = 21) and processed in parallel as formalin-fixed paraffin-embedded or snap-frozen samples. Serum samples were collected from patients with PF and healthy controls (n = 21). Neoepitope-specific biomarkers reflecting type III, IV, and VI collagen production (PRO-C3, PRO-C4, and PRO-C6) and degradation (C3M, C4M, C4Ma3, and C6M) were quantified in serum and proteolytically degraded lung tissue, and their spatial distribution was assessed by immunohistochemistry in lung tissue sections. ResultsAll collagen remodeling biomarkers were significantly increased in serum of patients with PF compared with healthy controls (PRO-C3: p = 0.0006, all others: p < 0.0001). Collagen degradation fragments (C3M, C4M, and C6M) could be generated and released from both non-fibrotic and fibrotic human lung tissue following proteolytic cleavage with pepsin, collagenase, and/or MMP-9. All biomarkers were detected in lung tissue by immunohistochemical staining, with widespread distribution of type III and IV collagen fragments, whereas type VI collagen (PRO-C6) production showed a more compartment-specific pattern. ConclusionsThese findings demonstrated that neoepitope-specific collagen remodeling biomarkers, usually detected in circulation, are present and can be released from human lung tissue. Their spatial distribution suggests that ECM remodeling is heterogeneous and differs according to collagen type and distinct tissue compartments. Collectively, our findings support the use of collagen remodeling biomarkers as tools to assess ECM remodeling in pulmonary disease.

IntroductionPrevious studies have shown that Aquamin(R), a multi-mineral extract from red marine algae, enhances barrier integrity proteins in the human colon. These findings prompted further investigation into Aquamin(R)s effects on gastrointestinal barrier function and permeability. MethodsSubjects with mild or in remission ulcerative colitis (UC) and healthy controls were enrolled in an open-label trial and received Aquamin(R) capsules (800 mg calcium/day) for 90 days. Intestinal permeability was evaluated before and after the 90-day intervention by urinary mannitol excretion after ingestion of a 5 g mannitol solution, with collections across several time intervals (pre-drink, 0-2 h, 2-8 h, and 8-24 h). The primary outcome was the change in mannitol excretion. Serum samples were also collected to assess liver and renal function. ResultsIn this pilot study (NCT04855799), which included UC patients and healthy controls (n = 8 per group), baseline urine mannitol levels in the 0-2 h sample were 54% higher in UC patients compared to healthy subjects (p = 0.006). Following 90 days of Aquamin(R) supplementation, urinary mannitol levels in UC patients decreased by 28%, 26%, and 41% at the 0-2 h, 2-8 h, and 8-24 h timepoints, respectively; the reduction at the 0-2 h interval reached statistical significance (p = 0.015). Overall, Aquamin(R) supplementation reduced total post-intervention mannitol excretion by 29% (p = 0.024). Aquamin(R) was well tolerated, with no serious adverse events reported. The serum metabolic panel revealed a modest but statistically significant reduction in alkaline phosphatase levels after 90 days of intervention. ConclusionThese results provide preliminary evidence that Aquamin(R) supplementation beneficially modulates gut barrier function and supports epithelial integrity in UC patients. These findings support further investigation of Aquamin(R) as a safe and promising adjunct to current UC management strategies, with potential utility as a barrier therapy in UC. SummaryAquamin(R) supplementation for 90 days reduced intestinal permeability in ulcerative colitis patients, as measured by urinary mannitol excretion. The intervention was well tolerated, suggesting Aquamin(R) may be a safe, promising adjunct for enhancing gut barrier function in UC management.

RationaleBronchopulmonary dysplasia (BPD), the lung disease associated with premature birth, is a significant health problem, often with long-term respiratory consequences. Recent research has highlighted the potential role of the lung and gut microbiome in the development and progression of BPD, yet it is unclear what aspects of the microbiome may contribute to BPD susceptibility. ObjectivesTo comprehensively characterize the lung and gut microbiomes of preterm infants and identify shared microbial taxa that are associated with BPD development. MethodsTracheal aspirate and stool samples were collected from 39 premature infants over the first month of life. To assess the taxonomic microbial composition of the lung and gut, samples were analyzed using shotgun metagenomic sequencing. BPD classification was determined using the National Institute of Child Health and Human Development severity-based definition at 36 weeks postmenstrual age. Measurements and Main ResultsMicrobial communities of the lung and gut were significantly different between infants who went on to develop BPD and those who did not, with an enrichment of skin-associated microbial genera such as Staphylococcus, Corynebacterium, and Cutibacterium in infants who developed BPD. Specifically, Staphylococcus epidermidis was enriched in premature infants who developed BPD and was the most prominent species shared between lung and gut communities. Temporal changes in gut microbial communities co-occurred with feeding practices and antibiotic exposure, suggesting an influence of external factors on microbiome composition. ConclusionsOur findings provide evidence that certain microbial colonization patterns among premature infants are closely associated with the pathogenesis and progression of BPD.

1Opportunistic, biofilm-forming pathogens such as Pseudomonas aeruginosa can employ an array of strategies to reduce the impact of antibiotics on their survival. The biofilm matrix can prevent antibiotics from reaching bacteria embedded within it; general changes in metabolic activity alter susceptibility to specific drugs dependent on the target; changes in the membrane and the expression of channel or pump proteins embedded within it affect drug uptake and efflux; and production of antibiotic-degrading enzymes can remove the threat. In this study, we report that biofilm-deficient mutants of two well-studied lab strains of P. aeruginosa (PA14 and PAO1) have wild-type (WT) levels of tolerance to colistin and meropenem when allowed to establish mature populations in an ex vivo pig lung model of cystic fibrosis lung infection. The biofilm defects in the mutants were confirmed using SEM, and cryoSEM was used to visualise the hydrated biofilm matrix in the WT. Using RNA sequencing of the PA14 WT and an isogenic mutant lacking the pel polysaccharide, we were able to identify a small number of differences in the responses of the two genotypes to the lung environment and to exposure to sub-bactericidal colistin in the lung model. Notably, there was differential upregulation of the MexXY-OprM and MexEF-OprN multidrug efflux pumps. However, the relative roles of biofilm matrix versus cellular changes in physiology in conferring antibiotic tolerance in this environment remain to be fully elucidated.

Objectives: Patients with Cystic fibrosis (CF) often receive aminoglycosides (AGs) to manage recurrent pulmonary infections, placing them at risk for ototoxicity. Chronic AG use can lead to complex cochlear damage affecting inner and outer hair cells, the stria vascularis, and spiral ganglion neurons. The greatest damage is typically in the basal cochlear region, which encodes high-frequency hearing, with additional involvement of more apical regions. While extended-high-frequency (EHF) hearing loss (EHFHL; 9-16 kHz) is often the earliest sign of AG ototoxicity, speech in noise (SiN) effects are rarely studied. Our overall hypothesis is that SiN perception difficulties in individuals with CF, treated with AGs, are related to combined cochlear and neural damage, primarily in the EHF range but also in the standard frequency (SF; 0.25-8 kHz) range. Three mechanisms that contribute to SiN perception were evaluated in children and young adults: 1) a primary effect of reduced EHF sensitivity, measured by pure-tone audiometry (PTA) and transient-evoked otoacoustic emissions (TEOAEs); 2) a secondary effect of subclinical damage in the SF range, measured by PTA and TEOAEs; and 3) additional neural effects, measured by middle ear muscle reflex (MEMR) threshold (afferent) and growth functions (efferent).Design:A total of 185 participants were enrolled; 101 individuals with CF treated with intravenous AGs and 84 age and sex-matched Controls without hearing concerns or CF. Assessments included EHF and SF PTA; the Bamford-Kowal-Bench (BKB)-SIN test for SiN perception; double-evoked TEOAEs with chirp stimuli from 0.71 to 14.7 kHz; and ipsilateral and contralateral wideband MEMR thresholds and growth functions using broadband stimuli. Results: Reduced sensitivity at EHFs (PTA, TEOAEs) was not associated with impaired SiN perception in the CF group. SF hearing, regardless of EHF status, was the primary predictor of SiN performance in the CF group. Increased MEMR growth was also significantly associated with poorer SiN in the CF group. Conclusions: In CF, impaired SiN perception was primarily predicted by SF hearing impairment, with additional involvement of the efferent auditory pathway through increased MEMR growth. These results build on prior evidence for efferent neural effects due to ototoxic exposures, supporting both sensory (afferent) and neural (efferent) mechanisms that contribute to listening difficulties in CF. Thus, preventive and intervention strategies should consider these combined mechanisms in people with AG ototoxicity to address their SiN problems.