Cystic fibrosis

Aqueous extracts of Moringa oleifera and Cinnamomum cassia as promising sources of antibiofilm compounds against mucoid and small colony variants of Pseudomonas aeruginosa and Staphylococcus aureus

Bacterial biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa pose significant challenges in treating cystic fibrosis (CF) airway infections due to their resistance to antibiotics. New therapeutic approaches are urgently needed to treat these chronic infections. This study aimed to investigate the antibiofilm potential of various plant extracts, specifically targeting mucoid and small colony variants of P. aeruginosa and S. aureus and strains. Moreover, it aimed to gain insights into the mechanisms of action and the potential phytochemicals responsible for antibiofilm activity. Solid-liquid extractions were performed on seven biomasses using water and ethanol (70 and 96 %) under controlled conditions, resulting in 21 distinct plant extracts. These extracts were evaluated for extraction yield, antioxidant activity, phenolic content, chemical composition by HPLC-TOF-MS, and antibiofilm activity using a 96-well plate assay, followed by crystal violet staining, bacterial adhesion assessment, and brightfield microscopy. Our findings revealed that aqueous extracts exhibited the highest inhibition of biofilm formation, with cinnamon bark and moringa seeds showing strong antibiofilm activity against both bacterial species. Brightfield microscopy confirmed that these extracts effectively inhibited biofilm formation. Chemical analysis identified key bioactive compounds, including moringin, benzaldehyde, coumarin, and quinic acid, which likely contribute to the observed antibiofilm effects. Recognizing that the antibiofilm properties of moringin, a common compound in both moringa seed and cinnamon bark extracts, remain underexplored, we conducted potential target identification via PharmMapper and molecular docking analyses to provide a foundation for future research. Computational analyses indicated that moringin might inhibit aspartate-semialdehyde dehydrogenase in P. aeruginosa and potentially interact with an unknown target in S. aureus. In conclusion, moringa seed and cinnamon bark extracts demonstrated significant potential for developing new therapies targeting biofilm-associated infections in CF. Further studies are needed to validate the computational predictions, identify the bacterial targets, and elucidate the precise mechanisms behind moringin's antibiofilm activity, which is likely the potential key contributor to the observed activity of the moringa and cinnamon bark extracts.

Imaging of cystic fibrosis manifestations in the abdomen

Cystic fibrosis is a common inherited autosomal recessive disease affecting 35,000 persons in the United States. It is caused by mutations of the cystic fibrosis transmembrane regulator (CFTR) gene, located on the long arm of chromosome 7.This protein carries chlorine in the membranes of epithelial cells of exocrine glands. Mutations in the CFTR gene results in production of abnormally viscous mucus. Although it primarily affects the lungs, cystic fibrosis is a multisystem disease with involvement of extra thoracic organs including the liver, pancreas, kidneys and digestive tract.With advances in the management of cystic fibrosis resulting in improved life expectancy, cystic fibrosis patients are surviving into adulthood and extrapulmonary disease has become more commonplace. It is essential that radiologists are aware of the spectrum of potential manifestations of cystic fibrosis to allow accurate diagnosis.The purpose of this manuscript is to provide an overview of the pathophysiology and imaging findings of abdominal entities unique to patients with cystic fibrosis. We will present a wide spectrum of renal, pancreatic, gastrointestinal, hepatobiliary and post-transplant cases describing the typical findings that will assist radiologists in providing a timely diagnosis for patients with cystic fibrosis.

The Association of Achromobacter xylosoxidans Airway Infection with Disease Severity in Cystic Fibrosis

Background/Objectives: The prevalence of Achromobacter xylosoxidans is increasing in people with Cystic Fibrosis (pwCF), yet its clinical pathogenicity remains controversial. The objective of this study was to chart the longitudinal prevalence and examine clinical associations before and after infection. Methods: This observational, retrospective study was conducted at a single CF center over a 14-year period. Data were collated from patient charts and clinic databases. Patients with Achromobacter sputum cultures were compared to those without the bacterium and analyzed according to whether they had single, intermittent, or chronic infections. Results: During the study period, an annual average of 124 pwCF were followed up at our clinic, with a median age of 13.6 years (IQR = 7.6-27.7). The Achromobacter detection rate increased from 0 to 6.1%. Twenty-three percent (29/124) of patients had at least one positive culture. The median age at acquisition was 17 years (IQR = 14.5-33). At the time of acquisition, the median FEV1 was 81% (IQR = 46-94), compared to 90% (IQR = 72-99) for patients without Achromobacter, p < 0.001. Patients with Achromobacter tended to demonstrate more chronic Pseudomonas (55% vs. 27%, p = 0.06) and pancreatic insufficiency (66% vs. 47%, p = 0.07). At two years post-acquisition, the median FEV1 for patients with intermittent and chronically infected decreased by 11.5% (IQR = -3.75-7.5), compared to 1.5% (IQR = -2.5-12.5) for those with a single positive culture, p = 0.03. Similarly, pulmonary exacerbations per year became more frequent post-acquisition in intermittent and chronically infected patients: Median (range) 2.5 (0-8) pre-, versus 3.0 (0-9) post-acquisition, p = 0.036. Conclusions: Chronic and intermittent infection with Achromobacter were associated with accelerated lung function decline and increased exacerbation frequency. Larger prospective studies are needed to confirm these findings and examine the effect of eradication on the clinical course.

Airway clearance therapy: experiences and perceptions of adults living with cystic fibrosis

Purpose: Adherence to airway clearance therapy (ACT) among individuals with cystic fibrosis (CF) is often inconsistent. This study aims to explore the perceptions of adults with CF regarding their experiences with ACT and what influences their selection of specific ACTs. Findings may help inform clinician approaches to patient care and ACT. Materials and Methods: A qualitative descriptive study was conducted using individual, semi-structured interviews. Eight participants [six male and two female, median (min-max) age 42.5 (27-52)] were purposively recruited from the Toronto Adult CF Centre at St. Michael's Hospital, Unity Health Toronto. Results: Four key themes were generated from participants' accounts. First, they described the intensive nature of CF self-management and its influence on their perceptions and selection of ACT techniques. Second, they emphasized the importance of healthcare professional guidance in treatment decisions. Third, physical health status, exercise, and CF transmembrane conductance regulator modulator therapy also shaped participants' self-management approaches. Lastly, their social context influenced how they navigated self-management, which evolved over time. Conclusion: This study shows that ACT technique selection is influenced by various evolving needs across the lifespan. Understanding the role that patient experiences play in ACT technique selection may help clinicians personalize recommendations and promote patient-centred care.

ExoS effector in Pseudomonas aeruginosa Hyperactive Type III secretion system mutant promotes enhanced Plasma Membrane Rupture in Neutrophils

Pseudomonas aeruginosa is an opportunistic pathogen responsible for airway infections in immunocompromised individuals, including those with cystic fibrosis (CF). P. aeruginosa has a type III secretion system (T3SS) that translocates effectors into host cells. ExoS is a T3SS effector with ADP ribosyltransferase (ADPRT) activity. ExoS ADPRT activity promotes P. aeruginosa virulence by inhibiting phagocytosis and limiting oxidative burst in neutrophils. The P. aeruginosa T3SS also translocates flagellin, which can activate the NLRC4 inflammasome, resulting in: 1) gasdermin-D pores, release of IL-1β and pyroptosis; and 2) histone 3 citrullination (CitH3), nuclear DNA decondensation and expansion into the neutrophil cytosol with incomplete NET extrusion. However, studies with P. aeruginosa PAO1 indicate that ExoS ADPRT activity inhibits the NLRC4 inflammasome in neutrophils. Here, we identified an ExoS+ CF clinical isolate of P. aeruginosa with a hyperactive T3SS. Variants of the hyperactive T3SS mutant or PAO1 were used to infect neutrophils from C57BL/6 mice that were wildtype or engineered to have a CF genotype or defects in inflammasome assembly. Responses to NLRC4 inflammasome assembly or ExoS ADPRT activity were assayed and found to be similar for C57BL/6 or CF neutrophils. ExoS ADPRT activity in the hyperactive T3SS mutant regulated inflammasome, nuclear DNA decondensation and incomplete NET extrusion responses, like PAO1, but promoted enhanced CitH3 and plasma membrane rupture (PMR). Glycine supplementation inhibited PMR by the hyperactive T3SS mutant, suggesting ninjurin-1 is required for this process. These results identify enhanced neutrophil PMR as a pathogenic activity of ExoS ADPRT in hypervirulent P. aeruginosa.

Measurement properties of the Polish version of the Cystic Fibrosis Questionnaire Revised 14+ in the adult population

Measuring the quality of life in patients with cystic fibrosis is an important element of the patient care process. Many tools have been created for this measurement among adults. One of them is the Cystic Fibrosis Questionnaire-Revised 14+ (CFQ-R 14+). Its measurement properties have not been comprehensively assessed in the population of Polish adults. The aim of the study is to verify the construct validity, including structural and criterion validity, as well as internal consistency, of the Polish version of the CFQ-R 14+ in the population of adults with cystic fibrosis. We conducted a cross-sectional survey among adults with cystic fibrosis. After preparing the database, we performed a confirmatory factor analysis (CFA) followed by exploratory factor analysis (EFA) using the parallel analysis method principal axis factoring with Oblimin rotation. Intercorrelations of questionnaire factors and the occurrence of relationships among items for the general scale results was checked. We also presented basic descriptive statistics (mean, median, standard deviation, skewness, kurtosis, minimum and maximum values). The analyses included responses from 220 adult patients. CFA results did not show adequate goodness of fit (χ2(1025) = 2112.35, p < 0.001; CFI = 0.831; TLI = 0.814; RMSEA = 0.069; SRMR = 0.074). After EFA, 6 factors were extracted, considering 40 out of 50 questions of the CFQ-R 14+. CFQ-R 14+ may be useful in assessing the quality of life of Polish adult patients with cystic fibrosis. Our analysis demonstrates that the optimal factor structure of the tool in this population includes 6 scales.

Sweat chloride reflects CFTR function and correlates with clinical outcomes following CFTR modulator treatment

BACKGROUND

Highly effective CFTR modulators improve CFTR function and lead to dramatic improvements in health outcomes in many people with cystic fibrosis (pwCF). The relationship between measures of CFTR function, such as sweat chloride concentration, and clinical outcomes in pwCF treated with CFTR modulators is poorly defined. We conducted analyses to better understand the relationships between sweat chloride and CFTR function in vitro, and between sweat chloride and clinical outcomes following CFTR modulator treatment.

METHODS

Mean sweat chloride values in healthy people, CF carriers, and pwCF treated with CFTR modulators at different doses were compared to chloride transport in corresponding human bronchial epithelial (HBE) cells. A pooled analysis of phase 3 CFTR modulator studies was performed to evaluate the relationship between attained values of sweat chloride and improvements in lung function, body mass index (BMI), patient reported outcomes, pulmonary exacerbations, and lung function change over time.

RESULTS

Sweat chloride concentrations in vivo correlated strongly with CFTR-dependent chloride current in HBE cells in vitro. Sweat chloride values of <30 mmol/L and ≥30 to <60 mmol/L in pwCF following CFTR modulator treatment were associated with better clinical outcomes than sweat chloride ≥60 to <80 mmol/L and ≥80 mmol/L.

CONCLUSIONS

In pwCF treated with CFTR modulators, lower sweat chloride levels (reflecting greater CFTR function) are associated with better clinical outcomes. These results support the therapeutic strategy of further restoring CFTR function towards normal, as reflected in lowering sweat chloride to below the diagnostic threshold for CF (<60 mmol/L) and to normal (<30 mmol/L), with CFTR modulators.

Formulate a concentrated highly branched poly(β-amino ester)/DNA polyplex - one step closer to application in lung cystic fibrosis disease

OBJECTIVE

Highly branched poly(β-amino ester) (HPAEs)-based gene therapy holds promise for treating lung cystic fibrosis (CF). However, the translation of HPAEs/DNA nanoparticles into clinical applications poses a significant challenge due to the requirement for high concentrations of the formulation.

METHODS

In this work, a straightforward and scalable concentration method was developed for concentrating HPAEs/DNA polyplexes. A series of different buffers with various pH values and ionic components were initially tested to develop the optimized HPAEs/DNA polyplex formulation. Subsequently, the optimized HPAEs/DNA polyplex formulation was concentrated through lyophilization and ultrafiltration.

RESULTS

The ultrafiltration outperformed the lyophilization in concentration capacity, showing a 24-fold increase in the concentrated formulation compared to the original non-concentrated formulation. The concentration does not disturb the transfection efficiency in lung CF epithelial cells, indicating its potential for lung delivery applications. Moreover, the concentrated HPAEs/DNA polyplex successfully restored the production of CF transmembrane conductance regulator (CFTR) protein in primary lung CF epithelial cells, surpassing the performance of the non-concentrated common gene transfection reagents such as Lipofectamine 3000 and Xfect.

CONCLUSION

The concentrated HPAEs/DNA formulation represents a promising step forward for preclinical testing (e.g. in vivo evaluation), with further research needed to confirm its potential for clinical use.

Micro-physiological system of human lung: The current status and application to drug discovery

Various attempts have been made to elucidate the mechanisms of human lung development, its physiological functions, and diseases, in the hope of new drug discovery. Recent technological advancements in experimental animals, cell culture, gene editing, and analytical methods have provided new insights and therapeutic strategies. However, the results obtained from animal experiments are often inconsistent with those obtained from human data because of reproducibility issues caused by structural and physiological differences between mice and humans. In addition, it is not possible to accurately reproduce the internal environment of the human lung structure using conventional two-dimensional (2D) or three-dimensional (3D) cell culture methods. As a result, the micro-physiological system (MPS) technology, such as "lung-on-a-chip" that can culture human cells in a state close to human body environment have been developed, and its applications to disease models, toxicological studies, and drug discovery are accelerated worldwide. Here, we focus on the mimetics of the lung, including "lung-on-a-chip" technology, and review their recent progress, achievements and challenges. Finally, we discuss the role of these chips in drug discovery for refractory lung diseases.

The Long-Term Uptake of Home Spirometry in Regular Cystic Fibrosis Care: Retrospective Multicenter Observational Study

BACKGROUND

Home spirometers have been widely implemented in the treatment of people with cystic fibrosis (CF). Frequent spirometry measurements at home could lead to earlier detection of exacerbations. However, previous research indicates that the long-term use of home spirometry is not well maintained by people with CF.

OBJECTIVE

We aimed to gain insight into the long-term uptake of home spirometry in regular multicenter CF care.

METHODS

Home spirometers combined with a remote monitoring platform were introduced in the treatment of people with CF in 5 Dutch CF centers starting in April 2020. Usage data from April 2020 to December 2022 were analyzed retrospectively. Survival analyses were conducted to assess use consistency over time, and t tests were used to evaluate the impact of increased pulmonary symptoms on home spirometry frequency. The effect of the initiation of a new treatment, Elexacaftor/Tezacaftor/Ivacaftor, on use frequency over time was assessed in a subgroup of participants with repeated measures ANOVA.

RESULTS

During the observation period, a total of 604 people with CF were enrolled in the remote monitoring platform and 9930 home spirometry measurements were performed. After the initiation of home spirometry use, the number of users declined rapidly. One year after the initiation, 232 (54.2%) people with CF stopped using home spirometry. During the observation period, 67 (11.1%) users performed more than 20 measurements. Furthermore, the number of consistent home spirometry users decreased over time. After 600 days, only 1% of users had measured their lung function consistently every 31 days. Use frequency slightly increased during periods with increased pulmonary symptoms (ΔMean=0.45, t497.278=-4,197; P<.001) and showed an initial rise followed by a decrease after starting treatment with Elexacaftor/Tezacaftor/Ivacaftor (ΔMean=0.45, t497.278=-4,197; P<.001).

CONCLUSIONS

Consistent uptake of home spirometry in people with CF is low but increases around periods of changing symptoms. A clear strategy for the organization of remote care seemed to improve the long-term uptake of home spirometry. Nevertheless, home spirometry and its intensity are not a goal on their own but should be used as a tool to reach individual goals within local contexts.

Elexacaftor/tezacaftor/ivacaftor and inflammation in children and adolescents with cystic fibrosis: a retrospective dual-center cohort study

BACKGROUND

Cystic fibrosis (CF) is characterized by chronic neutrophilic inflammation in the airways. Elexacaftor/tezacaftor/ivacaftor (ETI) therapy has demonstrably improved clinical outcomes and quality of life in people with CF (pwCF), but its effects on systemic inflammatory parameters remain unclear.

OBJECTIVE

To evaluate the impact of ETI on systemic inflammation in children and adolescents with CF.

DESIGN

Retrospective, dual-center observational, propensity score-matching study of pediatric pwCF on ETI.

METHODS

PwCF aged ⩽ 18 years treated with ETI at two Italian reference centers were included in this study. Data on immunoglobulins (Ig) (A, G, and M), γ-globulin, leukocyte levels, percent predicted forced expiratory volume in the first second (ppFEV1), sweat chloride (SC) concentration, and sputum cultures were collected at baseline, 12, and 24 months of treatment. Laboratory data of a control group (pwCF, not in ETI therapy, same demographic characteristics as the study group) were also collected.

RESULTS

Sixty-six patients (30 males, median age: 12 years, F508del homozygous: 23) were included. Mean IgG levels (SD) significantly decreased (p = 0.001) from 1168.20 mg/dl (344.41) at baseline to 1093.05 mg/dl (258.73; 12 months) and 1092.87 mg/dl (232.42; 24 months). Similar reductions were observed for IgA and γ-globulin; IgM reduction was not statistically significant. Leukocyte levels also decreased significantly from 8.04 × 103/µl (3.23 × 103) at baseline to 6.61 × 103/µl (1.74 × 103) (12 months) and 6.45 × 103/µl (1.70 × 103; 24 months). As for the control group, no significant changes in the levels of Ig, leukocytes, and γ-globulin were detected throughout the study period (p > 0.05).The mean (SD) ppFEV1 and the overall mean (SD) SC concentration significantly decreased during the follow-up. Regarding cultures, 18 (27%) of the 27 patients positive (41%) for Staphylococcus aureus at baseline became negative during treatment. Three patients (4%) with persistently positive cultures for Pseudomonas aeruginosa during the first 12 months, became negative after 24 months. One patient (1.5%), with a baseline positive culture for Pseudomonas Aeruginosa, showed negative cultures after 12 months.

CONCLUSION

ETI treatment improved respiratory outcomes and significantly reduced values of IgG, IgA, γ-globulin, and leukocytes, suggesting an effect on the systemic inflammatory response. Further research is warranted to elucidate the role of inflammatory parameters in monitoring response to therapy.

Endogenous retroelement expression in modeled airway epithelial repair

Cystic fibrosis (CF) is an autosomal recessive genetic disorder characterized by impairment of the CF transmembrane conductance regulator (CFTR) via gene mutation. CFTR is expressed at the cellular membrane of epithelial cells and functions as an anion pump which maintains water and salt ion homeostasis. In pulmonary airways of CF patients, pathogens such as P. aeruginosa and subsequent uncontrolled inflammation damage the human airway epithelial cells (HAECs) and can be life-threatening. We previously identified that inhibiting endogenous retroelement (ERE) reverse transcriptase can hamper the inflammatory response to bacterial flagella in THP-1 cells. Here, we investigate how ERE expression is sensitive to HAEC repair and toll-like receptor 5 (TLR5) activation, a primary mechanism by which inflammation impacts disease outcome. Our results demonstrate that several human endogenous retroviruses (HERVs) and long interspersed nuclear elements (LINEs) fluctuate throughout the various stages of repair and that TLR5 activation further influences ERE expression. By considering the impact of the most common CF mutation F508del/F508del on ERE expression in unwounded HAECs, we also found that two specific EREs, L1FLnI_2p23.1c and HERVH_10p12.33, were downregulated in CF-derived HAECs. Collectively, we show that ERE expression in HAECs is sensitive to certain modalities reflective of CF pathogenesis, and specific EREs may be indicative of CF disease state and pathogenesis.

An update on multiple breath washout in children with cystic fibrosis

INTRODUCTION

Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the CF transmembrane regulator (CFTR) gene, leading to progressive lung disease and systemic complications. Lung disease remains the primary cause of morbidity and mortality, making early detection of lung function decline crucial. The Lung Clearance Index (LCI), derived from the multiple breath washout (MBW) test, has emerged as a sensitive measure for identifying early airway disease.

AREAS COVERED

This review examines the technical aspects and clinical relevance of LCI, its advantages over traditional lung function tests, and its application in CF clinical trials. A focused literature review highlights LCI's utility in evaluating treatment efficacy and its potential integration into routine CF care.

EXPERT OPINION

LCI is more sensitive than spirometry for detecting early lung function decline and is predominantly used in pediatric settings. Its use is expanding in adult CF populations as advances in treatment allow adults to maintain stable lung function. In clinical trials, LCI is widely recognized as an outcome measure. While implemented into clinical care in many centers in Europe, this is not yet the case in North America. Faster testing protocols and point-of-care interpretation tools will support LCI's integration into routine CF monitoring.

Emerging roles of mechanosensitive ion channels in ventilator induced lung injury: a systematic review

Background

The pathogenetic mechanisms of ventilator-induced lung injury (VILI) still need to be elucidated. The mechanical forces during mechanical ventilation are continually sensed and transmitted by mechanosensitive ion channels (MSICs) in pulmonary endothelial, epithelial, and immune cells. In recent years, MSICs have been shown to be involved in VILI.

Methods

A systematic search across PubMed, the Cochrane Library, Web of Science, and ScienceDirect was performed from inception to March 2024, and the review was conducted in accordance with PRISMA guidelines. The potential eligible studies were evaluated by two authors independently. Study characteristics, quality assessment, and potential mechanisms were analyzed.

Results

We included 23 eligible studies, most of which were performed with murine animals in vivo. At the in vitro level, 52% and 48% of the experiments were conducted with human or animal cells, respectively. No clinical studies were found. The most reported MSICs include Piezo channels, transient receptor potential channels, potassium channels, and stretch-activated sodium channels. Piezo1 has been the most concerned channel in the recent five years. This study found that signal pathways, such as RhoA/ROCK1, could be enhanced by cyclic stretch-activated MSICs, which contribute to VILI through dysregulated inflammation and immune responses mediated by ion transport. The review indicates the emerging role of MSICs in the pathogenesis of VILI, especially as a signal-transmitting link between mechanical stretch and pathogenesis such as inflammation, disruption of cell junctions, and edema formation.

Conclusions

Mechanical stretch stimulates MSICs to increase transcellular ion exchange and subsequently generates VILI through inflammation and other pathogeneses mediated by MSICs signal-transmitting pathways. These findings make it possible to identify potential therapeutic targets for the prevention of lung injury through further exploration and more studies.

Systematic review registration

https://inplasy.com/inplasy-2024-10-0115/, identifier INPLASY2024100115.

One year of ETI reduces lung bacterial colonisation in adults with cystic fibrosis

The triple combination elexacaftor-tezacaftor-ivacaftor (ETI) has provided unprecedented clinical benefits for people with cystic fibrosis (pwCF) and drastically transformed the outcome of this disease. We aimed to describe the evolution of lung bacterial colonization in 198 French adult pwCF taking into account the use of concomitantly respiratory treatment. We collected sputum cultures produced during the entire follow-up period starting 3 years before and ending 1 year after ETI initiation. All sputum cultures were centralized and analyzed at our bacteriological laboratory. Clinical data included pulmonary function, respiratory treatments, physiotherapy, number of IV antibiotics treatment, as well as inpatient stays. We observed a significant decrease in colonization prevalence by any CF pathogen after one year of treatment with ETI (p < 0.001). This decrease was confirmed for Pseudomonas aeruginosa, MRSA and MSSA, Stenotrophomonas maltophilia, Achromobacter spp. and nontuberculous mycobacteria (NTM). The maximal density of bacteria documented in sputum cultures decreased from 2.107 CFU/ml to 1.106 CFU/ml after one year of ETI. We also found a decrease in prevalence of Pseudomonas aeruginosa chronic colonization and in the density of Pseudomonas aeruginosa after one year of ETI. These results confirm the decrease in prevalence and bacterial density of lung colonisation for most of the CF pathogens, including Achromobacter spp, Stenotrophomonas maltophilia concomitantly to the clinical improvement. Further studies are needed to better understand the underlying mechanisms of these microbiological changes.

Early nasal microbiota and subsequent respiratory tract infections in infants with cystic fibrosis

BACKGROUND

Respiratory tract infections (RTIs) drive lung function decline in children with cystic fibrosis (CF). While the respiratory microbiota is clearly associated with RTI pathogenesis in infants without CF, data on infants with CF is scarce. We compared nasal microbiota development between infants with CF and controls and assessed associations between early-life nasal microbiota, RTIs, and antibiotic treatment in infants with CF.

METHODS

We included 50 infants with CF and 30 controls from two prospective birth cohorts followed throughout the first year of life. We collected 1511 biweekly nasal swabs and analyzed the microbiota after amplifying the V3-V4 region of the 16S rRNA gene. We conducted structured weekly interviews to assess respiratory symptoms and antibiotic treatment. We calculated generalized additive mixed models and permutational analysis of variance.

RESULTS

Here, we show that the nasal microbiota is already altered before the first RTI or antibiotic treatment in infants with CF. Microbiota diversity differs between infants with CF and controls following RTIs and/or antibiotic treatment. CF infants with lower α-diversity have a higher number of subsequent RTIs.

CONCLUSIONS

Early nasal microbiota alterations may reflect predisposition or predispose to RTIs in infants with CF, and further change after RTIs and antibiotic treatment. This highlights the potential of targeting the nasal microbiota in CF-related RTI management, while also questioning current practices in the era of novel modulator therapies.

Current knowledge on Inquilinus limosus, a scarcely researched human pathogen

Inquilinus limosus belongs to the class of the Alphaproteobacteria and was first described in 2002. So far, the species has mainly been isolated from respiratory specimens of patients with cystic fibrosis. A main characteristic of Inquilinus limosus is the prolonged time until bacterial colony growth is detectable. As the defined incubation times in many laboratories are too short to detect the growth of Inquilinus limosus, it is likely that the species is less frequently detected in the clinical setting than it actually occurs. This also explains why there are currently only very few data on the incidence available. Furthermore, as an uncommon pathogen, Inquilinus limosus may be familiar to only a few specialised clinicians. Due to these reasons, only little research (e.g. case reports and research papers) have been published on this species to date. However, given that a clear human pathogenic significance can be deduced from the existing literature, we have decided to present the current state of knowledge in this review and to address further aspects for the future elucidation of the pathogenesis of Inquilinus limosus.

Caries experience of people with cystic fibrosis: A systematic review

OBJECTIVES

Cystic Fibrosis is a multi-system disease, arising from a mutation of the cystic fibrosis transmembrane conductance regulator gene (CFTR). There is a lack of information regarding oral disease levels among people with cystic fibrosis. As part of an ongoing study assessing oral health in adults with cystic fibrosis at Cork University Dental School & Hospital, a systematic review of available literature was conducted to ascertain the caries experience of people with cystic fibrosis. The objective was to systematically present and evaluate the literature comparing caries experience between people with cystic fibrosis and people without cystic fibrosis.

METHODS

Five online databases were searched; Embase, Scopus, Web of Science Core Collection, Medline Ebsco and Cochrane Library. Studies that reported caries experience in people with cystic fibrosis were included in this review.

RESULTS

The initial search identified 1199 publications from online databases. Twenty-one studies were included for qualitative analysis. Fourteen studies reported a lower caries experience in children with CF compared to children without CF, five studies reported a higher caries experience in adults with CF, and two studies found inconclusive evidence regarding the association between caries experience and CF status. All studies had a risk of bias that may influence results.

CONCLUSION

Despite a lack of complete unanimity between all studies, there is a general trend that children with cystic fibrosis have a lower caries experience than their healthy counterparts, whereas adults with cystic fibrosis have a higher caries experience. The review highlights the need for further studies involving adults with cystic fibrosis as the majority of studies primarily consist of paediatric populations.

CLINICAL SIGNIFICANCE

Dental practitioners should be aware that adults with cystic fibrosis have higher caries experience. Tailored approaches to dental care specific to cystic fibrosis individuals should be developed.

Therapeutic Interventions for Pseudomonas Infections in Cystic Fibrosis Patients: A Review of Phase IV Trials

Pseudomonas aeruginosa (Pa) poses a significant threat to individuals with cystic fibrosis (CF), as this bacterium is highly adaptable and resistant to antibiotics. While early-stage Pa infections can often be eradicated with aggressive antibiotic therapy, chronic infections are nearly impossible to eliminate and require treatments that focus on long-term bacterial suppression. Without such suppression, these persistent infections can severely damage the lungs, leading to serious complications and a reduced life expectancy for CF patients. Evidence for a specific treatment regimen for managing Pa infections in CF patients remains limited. This narrative review provides a detailed analysis of antimicrobial therapies assessed in completed phase IV trials, focusing on their safety and efficacy, especially with prolonged use. Key antibiotics, including tobramycin, colistin, meropenem, aztreonam, ceftolozane/tazobactam, ciprofloxacin, and azithromycin, are discussed, emphasizing their use, side effects, and delivery methods. Inhaled antibiotics are preferred for their targeted action and minimal side effects, while systemic antibiotics offer potency but carry risks like nephrotoxicity. The review also explores emerging treatments, such as phage therapy and antibiofilm agents, which show promise in managing chronic infections. Nonetheless, further research is necessary to enhance the safety and effectiveness of existing therapies while investigating new approaches for better long-term outcomes.

Genetic diagnosis and outcomes of intracytoplasmic sperm injection in South Chinese patients with congenital bilateral aplasia of the vas deferens

BACKGROUND

Obstructive azoospermia commonly is caused by CBAVD(Congenital Bilateral Aplasia of the Vas Deferens), mainly due to the cystic fibrosis transmembrane conductance regulator (CFTR) and adhesion G protein-coupled receptor G2(ADGRG2) mutations. The genetic landscape for Chinese CBAVD patients is unclear, leading to debates over genetic screening, counseling, and assisted reproduction strategies. This study investigates the prevalence of CFTR and ADGRG2 mutations in a southern Chinese cohort of CBAVD patients and evaluates the impact of CFTR mutations on intracytoplasmic sperm injection (ICSI) outcomes.

RESULTS

CFTR mutations were identified in 71.4% (30/42) of CBAVD patients, with a total of 36 CFTR mutation sites across 13 types identified, including two novel mutations. A novel ADGRG2 mutation was also detected. Betweenthe CFTR mutation-CBAVD group and the non-CBAVD OA group, a significant difference was observed only in the 2 Pronuclei(2PN) rate (79.5% vs 86.2%, P = 0.0065), while fertilization rates, pregnancy rates, miscarriage rates, and live birth rates showed no significant differences. Between the CFTR mutation-CBAVD group and the CBAVD group without CFTR mutation, there were no significant differences in fertilization rates, 2PN rates, pregnancy rates, miscarriage rates, or live birth rates.

CONCLUSION

Chinese CBAVD patients primarily exhibit mutations in the CFTR and ADGRG2 genes. Therefore, targeted gene testing for CFTR and ADGRG2 is more suitable compared to WES for CBAVD patients. Considering that the genetic factors of approximately 30% of CBAVD patients remain unknown, it is recommended to perform massive parallel sequencing for patients who test negative for CFTR and ADGRG2 gene screening. Despite these genetic factors, ICSI outcomes were not adversely affected, except for the 2PN rate. However, genetic counseling remains crucial for Chinese CBAVD patients before undergoing assisted reproduction.

Mucociliary clearance is impaired in small airways of cystic fibrosis pigs

Cystic fibrosis (CF) is a genetic disorder characterized by recurrent airway infections, inflammation, impaired mucociliary clearance, and progressive decline in lung function. The disease may start in the small airways; however, this is difficult to prove due to the limited accessibility of the small airways with the current single-photon mucociliary clearance assay. Here, we developed a dynamic positron emission tomography assay with high spatial and temporal resolution. We tested that mucociliary clearance is abnormal in the small airways of newborn cystic fibrosis pigs. Clearance of [68Ga]-tagged macroaggregated albumin from small airways started immediately after delivery and continued for the duration of the study. Initial clearance was fast but slowed down a few minutes after delivery. Cystic fibrosis pigs' small airways cleared significantly less than non-CF pigs' small airways (non-CF 25.1 ± 3.1% vs. CF 14.6 ± 0.1%). Stimulation of the cystic fibrosis airways with the purinergic secretagogue uridine-5'-triphosphate (UTP) further impaired clearance (non-CF with UTP 20.9 ± 0.3% vs. CF with UTP 13.0 ± 1.8%). None of the cystic fibrosis pigs treated with UTP (n = 6) cleared more than 20% of the delivered dose. These data indicate that mucociliary clearance in the small airways is fast and can easily be missed if the assay is not sensitive enough. The data also indicate that mucociliary clearance is impaired in the small airways of cystic fibrosis pigs. This defect is exacerbated by stimulation of mucus secretions with purinergic agonists.NEW & NOTEWORTHY We developed a novel positron emission tomography scan assay with unprecedented temporal and spatial resolution to measure mucociliary clearance in the small airways. We proved a long-standing but unproven assertion that mucociliary clearance is inherently abnormal in the small airways of newborn cystic fibrosis piglets that are otherwise free of infection or inflammation. This technique can be easily extended to other airway diseases such as asthma, idiopathic pulmonary fibrosis, or chronic obstructive pulmonary disease.

Exploring Therapeutic Strategies for Pediatric Cystic Fibrosis: An In-Depth Comparative Review

Cystic fibrosis (CF) is a genetic disorder that profoundly affects the respiratory and digestive systems, particularly in pediatric patients. This comprehensive review aims to conduct a comparative analysis of various treatment modalities employed in the management of CF in children. We systematically evaluated current literature focusing on pharmacological interventions, airway clearance techniques, nutritional management, and emerging therapies, including gene therapy and personalized medicine. Our analysis highlights the efficacy, safety, and accessibility of these treatments through a comparative lens, examining performance across diverse patient populations. Key comparisons include standard therapies, such as CF transmembrane conductance regulator (CFTR) modulators, versus traditional treatments and the effectiveness of airway clearance techniques in relation to lung function outcomes. We explore variations in treatment adherence and outcomes based on socioeconomic factors and healthcare systems. The review underscores the importance of individualized care plans tailored to the unique needs of pediatric patients. By synthesizing findings from clinical studies, meta-analyses, and expert guidelines, this review serves as a valuable resource for healthcare providers and researchers. Our goal is to optimize therapeutic strategies for pediatric patients with CF and ultimately improve their clinical outcomes.

A New Class of Polyion Complex Vesicles (PIC-somes) to Improve Antimicrobial Activity of Tobramycin in Pseudomonas Aeruginosa Biofilms

Pseudomonas aeruginosa (PA) is a major healthcare concern due to its tolerance to antibiotics when enclosed in biofilms. Tobramycin (Tob), an effective cationic aminoglycoside antibiotic against planktonic PA, loses potency within PA biofilms due to hindered diffusion caused by interactions with anionic biofilm components. Loading Tob into nano-carriers can enhance its biofilm efficacy by shielding its charge. Polyion complex vesicles (PIC-somes) are promising nano-carriers for charged drugs, allowing higher drug loadings than liposomes and polymersomes. In this study, a new class of nano-sized PIC-somes, formed by Tob-diblock copolymer complexation is presented. This approach replaces conventional linear PEG with brush-like poly[ethylene glycol (methyl ether methacrylate)] (PEGMA) in the shell-forming block, distinguishing it from past methods. Tob paired with a block copolymer containing hydrophilic PEGMA induces micelle formation (PIC-micelles), while incorporating hydrophobic pyridyldisulfide ethyl methacrylate (PDSMA) monomer into PEGMA chains reduces shell hydrophilicity, leads to the formation of vesicles (PIC-somes). PDSMA unit incorporation enables unprecedented dynamic disulfide bond-based shell cross-linking, significantly enhancing stability under saline conditions. Neither PIC-somes nor PIC-micelles show any relevant cytotoxicity on A549, Calu-3, and dTHP-1 cells. Tob's antimicrobial efficacy against planktonic PA remains unaffected after encapsulation into PIC-somes and PIC-micelles, but its potency within PA biofilms significantly increases.

Low-dose high-resolution chest CT in adults with cystic fibrosis: intraindividual comparison between photon-counting and energy-integrating detector CT

BACKGROUND

Regular disease monitoring with low-dose high-resolution (LD-HR) computed tomography (CT) scans is necessary for the clinical management of people with cystic fibrosis (pwCF). The aim of this study was to compare the image quality and radiation dose of LD-HR protocols between photon-counting CT (PCCT) and energy-integrating detector system CT (EID-CT) in pwCF.

METHODS

This retrospective study included 23 pwCF undergoing LD-HR chest CT with PCCT who had previously undergone LD-HR chest CT with EID-CT. An intraindividual comparison of radiation dose and image quality was conducted. The study measured the dose-length product, volumetric CT dose index, effective dose and signal-to-noise ratio (SNR). Three blinded radiologists assessed the overall image quality, image sharpness, and image noise using a 5-point Likert scale ranging from 1 (deficient) to 5 (very good) for image quality and image sharpness and from 1 (very high) to 5 (very low) for image noise.

RESULTS

PCCT used approximately 42% less radiation dose than EID-CT (median effective dose 0.54 versus 0.93 mSv, p < 0.001). PCCT was consistently rated higher than EID-CT for overall image quality and image sharpness. Additionally, image noise was lower with PCCT compared to EID-CT. The average SNR of the lung parenchyma was lower with PCCT compared to EID-CT (p < 0.001).

CONCLUSION

In pwCF, LD-HR chest CT protocols using PCCT scans provided significantly better image quality and reduced radiation exposure compared to EID-CT.

RELEVANCE STATEMENT

In pwCF, regular follow-up could be performed through photon-counting CT instead of EID-CT, with substantial advantages in terms of both lower radiation exposure and increased image quality.

KEY POINTS

Photon-counting CT (PCCT) and energy-integrating detector system CT (EID-CT) were compared in 23 people with cystic fibrosis (pwCF). Image quality was rated higher for PCCT than for EID-CT. PCCT used approximately 42% less radiation dose and offered superior image quality than EID-CT.

A New Frontier in Cystic Fibrosis Pathophysiology: How and When Clock Genes Can Affect the Inflammatory/Immune Response in a Genetic Disease Model

Cystic fibrosis (CF) is a monogenic syndrome caused by variants in the CF Transmembrane Conductance Regulator (CFTR) gene, affecting various organ and systems, in particular the lung, pancreas, sweat glands, liver, gastrointestinal tract, vas deferens, and vascular system. While for some organs, e.g., the pancreas, a strict genotype-phenotype occurs, others, such as the lung, display a different pathophysiologic outcome in the presence of the same mutational asset, arguing for genetic and environmental modifiers influencing severity and clinical trajectory. CFTR variants trigger a pathophysiological cascade of events responsible for chronic inflammatory responses, many aspects of which, especially related to immunity, are not ascertained yet. Although clock genes expression and function are known modulators of the innate and adaptive immunity, their involvement in CF has been only observed in relation to sleep abnormalities. The aim of this review is to present current evidence on the clock genes role in immune-inflammatory responses at the lung level. While information on this topic is known in other chronic airway diseases (chronic obstructive pulmonary disease and asthma), CF lung disease (CFLD) is lacking in this knowledge. We will present the bidirectional effect between clock genes and inflammatory factors that could possibly be implicated in the CFLD. It must be stressed that besides sleep disturbance and its mechanisms, there are not studies directly addressing the exact nature of clock genes' involvement in inflammation and immunity in CF, pointing out the directions of new and deepened studies in this monogenic affection. Importantly, clock genes have been found to be druggable by means of genetic tools or pharmacological agents, and this could have therapeutic implications in CFLD.

The Omega-6 Lipid pathway shift is associated with neutrophil influx and structural lung damage in early cystic fibrosis lung disease

Objectives

In cystic fibrosis (CF), an imbalanced lipid metabolism is associated with lung inflammation. Little is known about the role that specific lipid mediators (LMs) exert in CF lung inflammation, and whether their levels change during early disease progression. Therefore, we measured airway LM profiles of young CF patients, correlating these with disease-associated parameters.

Methods

Levels of omega (ω)-3/6 PUFAs and their LM derivatives were determined in bronchoalveolar lavage fluid (BALF) of children with CF ages 1-5 using a targeted high-performance liquid chromatography-tandem mass spectrometry approach. Hierarchical clustering analysis was performed on relative LM levels. Individual relative LM levels were correlated with neutrophilic inflammation (BALF %Neu) and structural lung damage (PRAGMA-CF %Disease). Significant correlations were included in a backward multivariate linear regression model to identify the LMs that are best related to disease progression.

Results

A total of 65 BALF samples were analysed for ω-3/6 lipid content. LM profiles clustered into an arachidonic acid (AA)-enriched and a linoleic acid (LA)-enriched sample cluster. AA derivatives like 17-OH-DH-HETE, 5-HETE, 5,15-diHETE, 15-HETE, 15-KETE, LTB4 and 6-trans-LTB4 positively correlated with BALF %Neu and/or PRAGMA %Dis. Contrastingly, 9-HoTrE and the LA derivatives 9-HoDE, 9(10)-EpOME, 9(10)-DiHOME, 13-HoDE, 13-oxoODE and 12(13)-EpOME negatively correlated with BALF %Neu and/or PRAGMA %Dis. 6-trans-LTB4 was the strongest predictor for BALF %Neu. 5-HETE and 15-KETE contributed most to PRAGMA %Dis prediction.

Conclusions

Our data provide more insight into the lung lipidome of infants with CF, and show that a shift from LA derivatives to AA derivatives in BALF associates with early CF lung disease progression.

[Self-care capacity of adult cystic fibrosis patients during transition/transfer between services]

BACKGROUND

To analyze the knowledge, abilities, and emotional state of cystic fibrosis patients during a specific follow-up period and compare this with the recall they had of the transition (planned and gradual shift from the pediatric unit) / transfer (direct change skipping the steps recommended by the guidelines) to a specialized cystic fibrosis adult unit.

METHODS

Prospective cross-sectional study with cystic fibrosis adult patients under follow-up in a specialist consultation. Group 1 were patients who transitioned and Group 2 were transferred patients. The following information was collected: sociodemographic variables, degree of knowledge, skills, and emotional state using a survey designed for this purpose (as part of the internal consistency validation process). Participants also completed the emotional subscale of Cystic Fibrosis Questionnaire-Revised. Inter-group comparisons were made for the transition/transfer, at the follow-up, and during the evolution.

RESULTS

Thirty-five patients were analyzed; 65.8% male; mean age 31.9 years (SD =10.1). At the transition, Group 1 (n=19; 54.3%) had greater knowledge about their medication and reduced ability to manage appointments and making decisions in comparison to Group 2 at transfer. At follow-up, Group 1 made a better report on their emotional state and significantly improved their ability to manage appointments, communication, and decision-making.

CONCLUSIONS

Patients who were moved to an adult cystic fibrosis unit through transition were more knowledgeable about their medications. However, those who were transferred managed their appointments and decision-making better, but felt sadder.

The airway mycobiome and interactions with immunity in health and chronic lung disease

The existence of commensal fungi that reside within the respiratory tract, termed the airway mycobiome, has only recently been discovered. Studies are beginning to characterize the spectrum of fungi that inhabit the human upper and lower respiratory tract but heterogeneous sampling and analysis techniques have limited the generalizability of findings to date. In this review, we discuss existing studies that have examined the respiratory mycobiota in healthy individuals and in those with inflammatory lung conditions such as asthma, chronic obstructive pulmonary disease and cystic fibrosis. Associations between specific fungi and features of disease pathogenesis are emerging but the precise functional consequences imparted by mycobiota upon the immune system remain poorly understood. It is imperative that further research is conducted in this important area as a more detailed understanding could facilitate the development of novel approaches to manipulating the mycobiome for therapeutic benefit.

Cystic fibrosis

Cystic fibrosis is a rare genetic disease caused by mutations in CFTR, the gene encoding cystic fibrosis transmembrane conductance regulator (CFTR). The discovery of CFTR in 1989 has enabled the unravelling of disease mechanisms and, more recently, the development of CFTR-directed therapeutics that target the underlying molecular defect. The CFTR protein functions as an ion channel that is crucial for correct ion and fluid transport across epithelial cells lining the airways and other organs. Consequently, CFTR dysfunction causes a complex multi-organ disease but, to date, most of the morbidity and mortality in people with cystic fibrosis is due to muco-obstructive lung disease. Cystic fibrosis care has long been limited to treating symptoms using nutritional support, airway clearance techniques and antibiotics to suppress airway infection. The widespread implementation of newborn screening for cystic fibrosis and the introduction of a highly effective triple combination CFTR modulator therapy that has unprecedented clinical benefits in up to 90% of genetically eligible people with cystic fibrosis has fundamentally changed the therapeutic landscape and improved prognosis. However, people with cystic fibrosis who are not eligible based on their CFTR genotype or who live in countries where they do not have access to this breakthrough therapy remain with a high unmet medical need.

Potential, Pitfalls, and Future Directions for Remote Monitoring of Chronic Respiratory Diseases: Multicenter Mixed Methods Study in Routine Cystic Fibrosis Care

BACKGROUND

The current literature inadequately addresses the extent to which remote monitoring should be integrated into care models for chronic respiratory diseases (CRDs).

OBJECTIVE

This study examined a remote monitoring program (RMP) in cystic fibrosis (CF) by exploring experiences, future perspectives, and use behavior over 3 years, with the aim of developing future directions for remote monitoring in CRDs.

METHODS

This was a mixed methods, multicenter, observational study in 5 Dutch CF centers following a sequential explanatory design. Self-designed questionnaires using the technology acceptance model were sent out to people with CF who had a minimum of 12 months of experience with the RMP and local health care professionals (HCPs). Questionnaire outcomes were used to inform semistructured interviews with HCPs and people with CF. Qualitative findings were reported following the COREQ (Consolidated Criteria for Reporting Qualitative Research) checklist. Anonymous data on use frequency of all people with CF were analyzed.

RESULTS

Between the second quarter of 2020 and the end of 2022, a total of 608 people with CF were enrolled in the program, and a total of 9418 lung function tests and 2631 symptom surveys were conducted. In total, 65% (24/37) of HCPs and 89% (72/81) of people with CF responded to the questionnaire, and 7 HCPs and 12 people with CF participated in semistructured interviews. Both people with CF and HCPs were positive about remote monitoring in CF care and found the RMP a good addition to daily care (people with CF: 44/72, 61%; HCPs: 21/24, 88%). Benefits ranged from supporting individual patients to reducing health care consumption. The most valued monitoring tool was home spirometry by both people with CF (66/72, 92%) and HCPs (22/24, 92%). Downsides included the potential to lose sight of patients and negative psychosocial effects, as 17% (12/72) of people with CF experienced some form of stress due to the RMP. A large majority of people with CF (59/72, 82%) and HCPs (22/24, 92%) wanted to keep using the RMP in future, with 79% (19/24) of HCPs and 75% (54/72) of people with CF looking forward to more replacement of in-person care with digital care during periods of well-being. Future perspectives for the RMP were centered on creating hybrid care models, personalizing remote care, and balancing individual benefits with monitoring burden.

CONCLUSIONS

Remote monitoring has considerable potential in supporting people with CF and HCPs within the CF care model. We identified 4 practice-based future directions for remote monitoring in CF and CRD care. The strategies, ranging from patient driven to prediction driven, can help clinicians, researchers, and policy makers navigate the rapidly changing digital health field, integrate remote monitoring into local care models, and align remote care with patient and clinician needs.

Glycemic Variability and the Thickness of Retinal Layers in Cystic Fibrosis Patients with and without Cystic Fibrosis Related Diabetes

PURPOSE

Patients with cystic fibrosis (CF) are at risk to develop CF related diabetes (CFRD) and subsequently even diabetic neuro- and/or vasculopathy. We sought to determine if there are typical signs of diabetes-related retinal alterations present in CF patients with preserved and impaired glycemic control.

METHODS

During routine annual examination CF patients were offered an additional 7-day period of real time continuous glucose monitoring (rtCGM) and an ophthalmological examination including retinal optical coherence tomography (OCT). Patients were categorized according to the glycemic control, i.e. the results of an oral glucose tolerance test (OGTT) and rtCGM were taken into consideration. OCT data was analyzed by our previously published visual analysis software generating dedicated and spatially resolved deviation maps for visualization and quantification of differences in total retinal thickness and thickness of retinal nerve fiber layer (RNFL) as well as ganglion cell layer (GCL) in comparison to age-matched healthy controls and patients with either type 1 or type 2 diabetes mellitus.

RESULTS

Results of the rtCGM and/or OGTT enabled discrimination between patients with normal glycemic control (CFNG; n = 6), with abnormal glycemic control (CFAG; n = 6) and overt CFRD (n = 4). OCT data indicates gradually increasing retinal thinning in all 3 groups, depending on the degree of glucose metabolism disorder compared to healthy controls. At the foveal region total retinal thickness and GCL thickness were significantly thinner in CFRD patients compared to CFNG patients (total retinal thickness: 260.4 µm (239.3-270.8) vs. 275.4 µm (254.3-289.5); GCL: 11.82 µm (11.16-15.25) vs. 17.30 µm (13.95-19.82); each p < 0.05).

CONCLUSION

Although we investigated a rather small number of patients, we obtained evidence that intraretinal neurodegenerative changes occur in each of our subgroups (CFNG, CFAG, CFRD). Beyond this, our results favor the detrimental role of additional diabetes, as the deviations from healthy controls were most pronounced in the CFRD group and are similar to those seen in patients suffering from type 1 or type 2 diabetes.

Cystic fibrosis-related metabolic defects: crosstalk between ion channels and organs

Cystic fibrosis is a debilitating disease characterized by a poor medical prognosis due to devastating lung injury. Recent medical advances targeting the major genetic mutation ΔF508 of the cystic fibrosis transmembrane conductance regulator (CFTR) protein have dramatically increased the lifespan of patients with this mutation. This development has led to major changes in the field and has pushed research beyond the ion transport nature of cystic fibrosis and toward multiorgan physiological reprogramming. In this issue of the JCI, Bae, Kim, and colleagues utilized a large animal pig model prior to the onset of disease. They revealed metabolic reprogramming and organ crosstalk that occurred prior to disease progression. These findings provide paradigm-shifting insight into this complex disease.

Randomised, phase 1/2a trial of ION-827359, an antisense oligonucleotide inhibitor of ENaC

Background

Hyperactivity of epithelial sodium channel (ENaC) with increased sodium absorption is a feature of cystic fibrosis (CF). ION-827359 is a 2.5-generation antisense oligonucleotide targeted to reduce ENaC protein. This study evaluated ION-827359 safety, pharmacokinetics and pharmacodynamics.

Methods

In this three-part phase 1/2a, double-blind, randomised study, healthy volunteers received single doses of placebo or ION-827359 (3, 10, 37.5 or 100 mg; Part 1) or multiple doses of placebo or ION-827359 (5×10 mg, 5×37.5 mg, 5×75 mg or 10×37.5 mg; Part 2). People with CF (pwCF) received multiple doses of placebo or ION-827359 (5×10 mg, 5×37.5 mg, 5×75 mg and 5×100 mg; Part 3). Treatments were administered via Pari eFlow© mesh nebuliser. The primary outcome was safety; pharmacokinetic and pharmacodynamic parameters were also assessed.

Results

64 healthy volunteers and 34 pwCF were enrolled. ION-827359 was well tolerated with an acceptable safety profile. There were no clinically relevant changes in laboratory values, ECG or vital signs. Systemic drug exposure was low (plasma half-life ∼2 weeks). Multiple doses of ION-827359 were associated with dose-dependent reductions in ENaC mRNA in bronchial epithelium. After multiple dosing, forced expiratory volume in 1 s was slightly higher in pwCF receiving ION-827359 (+2.9% with ION-827359 100 mg versus placebo; p=0.27).

Conclusions

The tolerability and safety of ION-827359 appear favourable at this stage of investigation. Reduction in ENaC mRNA supports mechanistic efficacy at the doses and regimens tested, and supports further investigation of ION-827359 in pwCF.

The clinical utility of sequencing the entirety of CFTR

BACKGROUND

Cystic fibrosis (CF) is caused by deleterious variants in each CFTR gene. We investigated the utility of whole-gene CFTR sequencing when fewer than two pathogenic or likely pathogenic (P/LP) variants were detected by conventional testing (sequencing of exons and flanking introns) of CFTR.

METHODS

Individuals with features of CF and a CF-diagnostic sweat chloride concentration with zero or one P/LP variants identified by conventional testing enrolled in the CF Mutation Analysis Program (MAP) underwent whole-gene CFTR sequencing. Replication was performed on individuals enrolled in the CF Genome Project (CFGP), followed by phenotype review and interrogation of other genes.

RESULTS

Whole-gene sequencing identified a second P/LP variant in 20/43 MAP enrollees (47 %) and 10/22 CFGP enrollees (45 %) who had one P/LP variant after conventional testing. No P/LP variants were detected when conventional testing was negative (MAP: n = 43; CFGP: n = 13). Genome-wide analysis was unable to find an alternative etiology in CFGP participants with fewer than two P/LP CFTR variants and CF could not be confirmed in 91 % following phenotype re-review.

CONCLUSIONS

Whole-gene CFTR analysis is beneficial in individuals with one previously-identified P/LP variant and a CF-diagnostic sweat chloride. Negative conventional CFTR testing indicates that the phenotype should be re-evaluated.

Cystic fibrosis cell models for high-throughput analysis and drug screening

Cystic fibrosis (CF) is a single-gene disorder that affects the lung, digestive system, and other organs. Mutations in the CF transmembrane conductance regulator (CFTR) gene are classified into several classes based on their pathogenic mechanism and clinical severity. The distinct and heterogeneous clinical behavior of each CF class and the respective CFTR mutations have made the development of a durable therapy for all CF patients extremely challenging. While the FDA-approved drug elexacaftor/tezacaftor/ivacaftor (Trikafta) benefits CF patients carrying at least one F508del mutation in CFTR, it's not effective for many CF patients carrying a variety of other CFTR mutations. To establish a better understanding of CF pathophysiology and aid the development of novel therapeutics for different classes of CF patients, we have created four CF-mutation-specific cell models that recapitulate respectively four distinct CF classes and disease phenotypes, as confirmed by sequencing, CFTR mRNA and protein quantification. The channel function of each cell model was first validated using a well-established FLIPR (Fluorescent Imaging Plate Reader) membrane potential assay and then assessed by the YFP-based functional assay. Integrated with a halide-sensitive fluorescent reporter, these CF cell models can be used for high-throughput drug screening, as demonstrated by a proof-of-concept study using Trikafta. These cell models have the potential to advance CFTR mutation-specific therapies thus addressing the unmet needs of CF patients with rare mutations.

In vivo editing of lung stem cells for durable gene correction in mice

In vivo genome correction holds promise for generating durable disease cures; yet, effective stem cell editing remains challenging. In this work, we demonstrate that optimized lung-targeting lipid nanoparticles (LNPs) enable high levels of genome editing in stem cells, yielding durable responses. Intravenously administered gene-editing LNPs in activatable tdTomato mice achieved >70% lung stem cell editing, sustaining tdTomato expression in >80% of lung epithelial cells for 660 days. Addressing cystic fibrosis (CF), NG-ABE8e messenger RNA (mRNA)-sgR553X LNPs mediated >95% cystic fibrosis transmembrane conductance regulator (CFTR) DNA correction, restored CFTR function in primary patient-derived bronchial epithelial cells equivalent to Trikafta for F508del, corrected intestinal organoids and corrected R553X nonsense mutations in 50% of lung stem cells in CF mice. These findings introduce LNP-enabled tissue stem cell editing for disease-modifying genome correction.

Assessing the Potential of N-Butyl-l-deoxynojirimycin (l-NBDNJ) in Models of Cystic Fibrosis as a Promising Antibacterial Agent

Over the past few years, l-iminosugars have revealed attractive pharmacological properties for managing rare diseases including Cystic Fibrosis (CF). The iminosugar N-butyl-l-deoxynojirimycin (l-NBDNJ, ent-1), prepared by a carbohydrate-based route, was herein evaluated for its anti-inflammatory and anti-infective potential in models of CF lung disease infection. A significant decrease in the bacterial load in the airways was observed in the murine model of Pseudomonas aeruginosa chronic infection in the presence of l-NBDNJ, also accompanied by a modest reduction of inflammatory cells. Mechanistic insights into the observed activity revealed that l-NBDNJ interferes with the expression of proteins regulating cytoskeleton assembly and organization of the host cell, downregulates the main virulence factors of P. aeruginosa involved in the host response, and affects pathogen adhesion to human cells. These findings along with the observation of the absence of an in vitro bacteriostatic/bactericidal action of l-NBDNJ suggest the potential use of this glycomimetic as an antivirulence agent in the management of CF lung disease.

Metabolic Modulation-Mediated Antibiotic and Immune Activation for Treatment of Chronic Lung Infections

The Pseudomonas aeruginosa biofilm in recalcitrant chronic lung infections not only develops high antimicrobial tolerance but also induces an aberrant host inflammatory response. The metabolic condition plays a vital role in both the antimicrobial susceptibility of bacteria and the inflammatory response of immune cells, thereby offering a potential therapeutic target. Herein, we described a metabolic modulation strategy by using ultrasound-responsive liposomal nanoparticles containing a sonosensitizer and a hypoxia-activated prodrug against biofilm-associated chronic lung infections. Under ultrasound stimulation, the sonosensitizer generates antibacterial reactive oxygen species by oxygen consumption. Subsequently, the oxygen consumption-mediated hypoxia not only induces the anaerobic metabolism of bacteria for antibiotic activation but also triggers the glycolysis pathway of immune cells for inflammatory activation. Such metabolic modulation strategy demonstrated efficient therapeutic efficacy for P. aeruginosa biofilm-induced chronic lung infections in mice models and provides a promising way for combating biofilm-associated chronic infections.

Current and future therapeutic approaches of CFTR and airway dysbiosis in an era of personalized medicine

Cystic fibrosis (CF) is a life-threatening genetic disorder caused by mutations in the CFTR gene. This leads to a defective protein that impairs chloride transport, resulting in thick mucus buildup and chronic inflammation in the airways. The review discusses current and future therapeutic approaches for CFTR dysfunction and airway dysbiosis in the era of personalized medicine. Personalized medicine has revolutionized CF treatment with the advent of CFTR modulator therapies that target specific genetic mutations. These therapies have significantly improved patient outcomes, slowing disease progression, and enhancing quality of life. It also highlights the growing recognition of the airway microbiome's role in CF pathogenesis and discusses strategies to modulate the microbiome to further improve patient outcomes. This review discusses various therapeutic approaches for cystic fibrosis (CFTR) mutations, including adenovirus gene treatments, nonviral vectors, CRISPR/cas9 methods, RNA replacement, antisense-oligonucleotide-mediated DNA-based therapies, and cell-based therapies. It also introduces airway dysbiosis with CF and how microbes influence the lungs. The review highlights the importance of understanding the cellular and molecular causes of CF and the development of personalized medicine to improve quality of life and health outcomes.

A new era of targeting cystic fibrosis with non-viral delivery of genomic medicines

Cystic fibrosis (CF) is a complex genetic respiratory disorder that necessitates innovative gene delivery strategies to address the mutations in the gene. This review delves into the promises and challenges of non-viral gene delivery for CF therapy and explores strategies to overcome these hurdles. Several emerging technologies and nucleic acid cargos for CF gene therapy are discussed. Novel formulation approaches including lipid and polymeric nanoparticles promise enhanced delivery through the CF mucus barrier, augmenting the potential of non-viral strategies. Additionally, safety considerations and regulatory perspectives play a crucial role in navigating the path toward clinical translation of gene therapy.

Neutrophil extracellular traps (NETs) and fibrotic diseases

Fibrosis, a common cause and serious outcome of organ failure that can affect any organ, is responsible for up to 45% of all deaths in various clinical settings. Both preclinical models and clinical trials investigating various organ systems have shown that fibrosis is a highly dynamic process. Although many studies have sought to gain understanding of the mechanism of fibrosis progression, their findings have been mixed. In recent years, increasing evidence indicates that neutrophil extracellular traps (NETs) are involved in many inflammatory and autoimmune disorders and participate in the regulation of fibrotic processes in various organs and systems. In this review, we summarize the current understanding of the role of NETs in fibrosis development and progression and their possibility as therapeutic targets.

Mucociliary Clearance is Impaired in Small Airways of Cystic Fibrosis Pigs

Rationale

Cystic fibrosis is a genetic disorder characterized by recurrent airway infections, inflammation, and progressive decline in lung function. Autopsy and spirometry data suggest that cystic fibrosis may start in the small airways which, due to the fractal nature of the airways, account for most of the airway tree surface area. However, they are not easily accessible for testing.

Objectives

Here, we tested the hypothesis that mucociliary clearance is abnormal in the small airways of newborn cystic fibrosis pigs.

Methods

Current mucociliary clearance assays are limited therefore we developed a dynamic positron emission tomography scan assay with high spatial and temporal resolution. Each study was accompanied by a high-resolution computed tomography scan that helped identify the thin outer region of the lung that contained small airways.

Measurements and Main Results

Clearance of aerosolized [ 68 Ga]macro aggregated albumin from distal airways occurred within minutes after delivery and followed a two-phase process. In cystic fibrosis pigs, both early and late clearance rates were slower. Stimulation of the cystic fibrosis airways with the purinergic agonist UTP further impaired late clearance. Only 1 cystic fibrosis pig treated with UTP out of 6 cleared more than 20% of the delivered dose.

Conclusions

These data indicate that mucociliary transport in the small airways is fast and can easily be missed if the acquisition is not fast enough. The data also indicate that mucociliary transport is impaired in small airways of cystic fibrosis pigs. This defect is exacerbated by stimulation of mucus secretions with purinergic agonists.

Arteriovenous metabolomics in pigs reveals CFTR regulation of metabolism in multiple organs

Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene cause cystic fibrosis (CF), a multiorgan disease that is characterized by diverse metabolic defects. However, other than specific CFTR mutations, the factors that influence disease progression and severity remain poorly understood. Aberrant metabolite levels have been reported, but whether CFTR loss itself or secondary abnormalities (infection, inflammation, malnutrition, and various treatments) drive metabolic defects is uncertain. Here, we implemented comprehensive arteriovenous metabolomics in newborn CF pigs, and the results revealed CFTR as a bona fide regulator of metabolism. CFTR loss impaired metabolite exchange across organs, including disruption of lung uptake of fatty acids, yet enhancement of uptake of arachidonic acid, a precursor of proinflammatory cytokines. CFTR loss also impaired kidney reabsorption of amino acids and lactate and abolished renal glucose homeostasis. These and additional unexpected metabolic defects prior to disease manifestations reveal a fundamental role for CFTR in controlling multiorgan metabolism. Such discovery informs a basic understanding of CF, provides a foundation for future investigation, and has implications for developing therapies targeting only a single tissue.

Bioengineering toolkits for potentiating organoid therapeutics

Organoids are three-dimensional, multicellular constructs that recapitulate the structural and functional features of specific organs. Because of these characteristics, organoids have been widely applied in biomedical research in recent decades. Remarkable advancements in organoid technology have positioned them as promising candidates for regenerative medicine. However, current organoids still have limitations, such as the absence of internal vasculature, limited functionality, and a small size that is not commensurate with that of actual organs. These limitations hinder their survival and regenerative effects after transplantation. Another significant concern is the reliance on mouse tumor-derived matrix in organoid culture, which is unsuitable for clinical translation due to its tumor origin and safety issues. Therefore, our aim is to describe engineering strategies and alternative biocompatible materials that can facilitate the practical applications of organoids in regenerative medicine. Furthermore, we highlight meaningful progress in organoid transplantation, with a particular emphasis on the functional restoration of various organs.

The hope, hype and obstacles surrounding cell therapy

Cell therapy offers hope, but it also presents challenges, most particularly the limited ability of human organs and tissues to regenerate. Since many diseases are associated with irreversible pathophysiological or traumatic changes, stem cells and their derivatives are unable to secure healing. Although regenerative medicine offers chances for improvements in many diseases, such as type one diabetes and Parkinson's disease, it cannot eliminate the primary cause of many of them. While successes can be expected for diseases such as sickle cell disease, this is not the case for hereditary diseases with varied mutation types or for ciliopathies, which start in embryogenesis. In this complicated medical environment, synthetic biology offers some solutions, but their implementation will take many years. Still, positive examples such as CAR-T therapy offer hope.

[A systemic gene therapy for the treatment of cystic fibrosis]

Le master I2VB se propose de donner les bases conceptuelles et pratiques des différents aspects de l’infectiologie. Il s’appuie sur une coopération exemplaire entre les équipes de recherche en infectiologie et en immunologie de l’Université de Tours, et celles, entre autres, de l’Unité Infectiologie et Santé Publique (ISP) du Centre INRAE de Tours-Nouzilly, concrétisée par une profonde interaction entre chercheurs et enseignants-chercheurs.

Cette formation aborde aussi bien les aspects fondamentaux et appliqués de l’infectiologie et de l’immunologie allant de l’étude moléculaire des interactions entre le pathogène et son hôte, jusqu’à la conception et la mise sur le marché des produits de la vaccinologie, des biothérapies anti-infectieuses et des anticorps immuno-thérapeutiques.

Le master I2VB (niveau M1) donne lieu aux parcours ICM, I&B et AcT (niveau M2).

Initial characteristics of cystic fibrosis in Algeria: Description of 34 pediatric cases

BACKGROUND

Cystic fibrosis (CF) is a rare disease in Algeria, and its prognosis is poor in developing countries. The clinical and demographic knowledge of Algerian pediatric patients diagnosed with CF is incomplete due to the nonexistence of a national medical registry. Hence, the present study is the first Algerian multicentre study on CF.

METHODS

This retrospective study was conducted in western Algeria. Over 1 year, the study included all pediatric patients with a confirmed diagnosis of CF in the pediatric hospital of Oran. Patient characteristics, clinical manifestations, and the prescribed treatment were reported.

RESULTS

Thirty-four children (16 boys and 18 girls) participated in this study. Only 15 were diagnosed before the age of 6 months. The sweat chloride test was positive in all patients. Respiratory manifestations were found in all patients, chronic diarrhoea in 29 of them, and growth retardation in 10. Moreover, 25 (73.5%) had low to low intermediate socioeconomic levels. After diagnosis, respiratory complications marked the evolution of the 34 patients, with bronchial congestion observed in 33 of them, while 10 (29.4%) patients presented severe bronchopneumonia and 4 (11.8%) were affected by asthma. Consequently,  three (8.8%) died at an average age of 9 years mainly because of respiratory failure.

CONCLUSION

The prognosis of CF is poor in Algeria compared to other developed countries due to the longer diagnostic delay and limited therapeutic alternatives. This representative subset of Algerian pediatric patients with CF will serve as a reference for future studies on CF in Algeria.

Real-world effectiveness of elexacaftor/tezacaftor/ivacaftor on the burden of illness in adolescents and adults with cystic fibrosis

Background

Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) has been shown to be safe and efficacious in people with cystic fibrosis (CF) aged ≥2 years. Here, we describe results from an observational study assessing change in burden of illness following initiating ELX/TEZ/IVA in real-world settings.

Methods

This US-based, multicenter, observational study used data from electronic medical records to evaluate real-world burden of illness before and after ELX/TEZ/IVA initiation in people with CF aged ≥12 years heterozygous for F508del and a minimal function mutation (F/MF) or an uncharacterized CFTR mutation. Endpoints included absolute change from baseline in percent predicted forced expiratory volume in 1 s (ppFEV1), body mass index (BMI) and BMI-for-age z-score, glycated hemoglobin (HbA1c), and numbers of pulmonary exacerbations (PEx).

Results

Overall, 206 people with CF were enrolled (mean [SD] age 22.5 [11.1] years; 192 [93.2%] with F/MF genotype). Mean follow-up was 15.6 (SD, 1.6) months. Improvements in ppFEV1 (7.3 [95% CI: 5.7, 8.8] percentage points) were observed from baseline through follow-up. Increases in BMI (1.40 [95% CI: 1.07, 1.77] kg/m2) and BMI-for-age z-score (0.14 [95% CI: 0.00, 0.28]) were also observed from baseline at 12 months. The estimated annualized rate of any PEx was 1.31 at baseline and 0.61 over follow-up (rate ratio 0.47 [95% CI: 0.39, 0.55]), with annualized rates of PEx requiring antibiotics and hospitalizations of 0.55 and 0.88 in the baseline period and 0.12 and 0.36 over follow-up (rate ratios 0.22 [95% CI: 0.15, 0.31] and 0.41 [95% CI: 0.32, 0.51]), respectively. Absolute change in HbA1c was -0.22 (95% CI: -0.38, -0.06) from baseline through follow-up.

Conclusions

ELX/TEZ/IVA treatment was associated with improved lung function, increased BMI, reduced frequency of PEx, and improved (i.e., reduced) HbA1c. These results confirm the broad clinical benefits of ELX/TEZ/IVA seen in clinical trials and show the potential for ELX/TEZ/IVA to improve markers of glucose metabolism.