Int Forum Allergy Rhinol. 2023 Feb 9. doi: 10.1002/alr.23136. Online ahead of print.

ABSTRACT

BACKGROUND: Chronic rhinosinusitis (CRS) is accompanied by burdensome co-morbid conditions. Understanding the relative timing of these conditions' onset could inform disease prevention, detection, and management.

OBJECTIVE: To evaluate the association between CRS and new onset and prevalent asthma, non-cystic fibrosis bronchiectasis (NCFBE), chronic obstructive pulmonary disease (COPD), gastroesophageal reflux disease (GERD), and obstructive sleep apnea (OSA).

METHODS: We conducted a prospective cohort study among primary care patients using a detailed medical and symptom questionnaire in 2014 and again in 2020. We used questionnaire and electronic health record (EHR) data to determine CRS status: CRSSE (moderate to severe symptoms with EHR evidence), CRSE (limited symptoms with EHR evidence), CRSS (moderate to severe symptoms without EHR evidence), CRSneg (limited symptoms and no EHR evidence; reference). We evaluated the association between CRS status and new onset and prevalent disease using logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS: There were 7,847 and 4,445 respondents to the 2014 and 2020 questionnaires, respectively. CRSSE (versus CRSneg ) was associated with increased odds of new onset asthma (OR:1.74; CI:1.09, 2.77), NCFBE (OR:1.87, CI:1.12, 3.13), COPD (OR:1.73; CI:1.14, 2.68), GERD (OR:1.95, CI:1.61, 2.35), and OSA (OR:1.91; CI:1.39, 2.62). Similarly increased odds were observed for associations with the prevalence of these conditions.

CONCLUSION: The findings from the study support further exploration of CRS as a target for the prevention and detection of asthma, NCFBE, COPD, GERD, and OSA. This article is protected by copyright. All rights reserved.

PMID:36756720 | DOI:10.1002/alr.23136

Nat Commun. 2023 Feb 8;14(1):693. doi: 10.1038/s41467-023-36244-2.

ABSTRACT

We are currently witnessing transformative change for people with cystic fibrosis with the introduction of small molecule, mutation-specific drugs capable of restoring function of the defective protein, cystic fibrosis transmembrane conductance regulator (CFTR). However, despite being a single gene disorder, there are multiple cystic fibrosis-causing genetic variants; mutation-specific drugs are not suitable for all genetic variants and also do not correct all the multisystem clinical manifestations of the disease. For many, there will remain a need for improved treatments. Those patients with gene variants responsive to CFTR modulators may have found these therapies to be transformational; research is now focusing on safely reducing the burden of symptom-directed treatment. However, modulators are not available in all parts of the globe, an issue which is further widening existing health inequalities. For patients who are not suitable for- or do not have access to- modulator drugs, alternative approaches are progressing through the trials pipeline. There will be challenges encountered in design and implementation of these trials, for which the established global CF infrastructure is a major advantage. Here, the Cystic Fibrosis National Research Strategy Group of the UK NIHR Respiratory Translational Research Collaboration looks to the future of cystic fibrosis therapies and consider priorities for future research and development.

PMID:36755044 | DOI:10.1038/s41467-023-36244-2

Biochim Biophys Acta Mol Basis Dis. 2023 Feb 6:166662. doi: 10.1016/j.bbadis.2023.166662. Online ahead of print.

ABSTRACT

Nonalcoholic steatohepatitis (NASH) is considered a pivotal stage in nonalcoholic fatty liver disease (NAFLD) progression and increases the risk of end-stage liver diseases such as fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). The etiology of NASH is multifactorial and identifying reliable molecular players has proven difficult. Presently, there are no approved drugs for NASH treatment, which has become a leading cause of liver transplants worldwide. Here, using public human transcriptomic NAFLD dataset, we uncover Cystic Fibrosis Transmembrane Conductance Receptor (CFTR) as a differentially expressed gene in the livers of human NASH patients. Similarly, murine Cftr expression was also found to be upregulated in two mouse models of diet-induced NASH. Furthermore, the pharmacological inhibition of CFTR significantly reduced NASH progression in mice and its overexpression aggravated lipotoxicity in human hepatic cells. These results, thus, underscore the involvement of murine Cftr in the pathogenesis of NASH and raise the intriguing possibility of its pharmacological inhibition in human NASH.

PMID:36754244 | DOI:10.1016/j.bbadis.2023.166662

J Pediatr Gastroenterol Nutr. 2023 Feb 8. doi: 10.1097/MPG.0000000000003730. Online ahead of print.

ABSTRACT

OBJECTIVES: Data on the phenotypes and disease outcomes of very early-onset inflammatory bowel disease (VEO-IBD) are limited. The aims of this study were to describe the clinical features, outcomes, and treatment response of VEO-IBD patients and to compare them with later-onset pediatric inflammatory bowel disease (P-IBD) patients.

METHODS: All consecutive patients aged 0 to 6 years who were diagnosed with Crohn's disease (CD), ulcerative colitis (UC), or IBD unclassified (IBD-U) at two academic hospitals from 2010 to March 2021 were included. They were compared to sex-matched IBD patients aged 6-17 years.

RESULTS: Two hundred thirty-two patients were included, 78 (34%) with VEO-IBD and 154 (66%) with P-IBD. IBD-U was the most common diagnosis in the VEO-IBD group compared to P-IBD (28% vs. 3%, p<0.001), while CD was predominant in older children (27% vs. 52%, p<0.001). The VEO-IBD group showed lower rates of clinical remission after induction with steroids compared to older children (82% vs. 93%, p=0.01), higher rates of steroid resistance (14% vs. 5%, p=0.02) and steroid dependence (27% vs. 8%, p<0.001). The number of patients who started anti-tumor necrosis factor (TNF)-α agents was similar between the groups. Anti-TNF-α retention was lower in the VEO-IBD group at 1 and 2 years (59% vs. 85%, p=0.003; 16% vs. 55%, p<0.001, respectively). Surgical risk appeared to be higher for VEO-IBD (32% vs. 14%, p<0.001).

CONCLUSIONS: When compared to P-IBD patients, patients with VEO-IBD may have a more severe disease course, a poorer response to steroids and anti-TNF-α agents and require more frequent surgical procedures.

PMID:36754082 | DOI:10.1097/MPG.0000000000003730

J Bras Pneumol. 2023 Feb 6;49(1):e20220306. doi: 10.36416/1806-3756/e20220306. eCollection 2023.

ABSTRACT

OBJECTIVE: To analyze the characteristics of cystic fibrosis (CF) care centers (CFCCs) in Brazil.

METHODS: A questionnaire was sent to the coordinators of all 51 registered CFCCs between May and September of 2021.

RESULTS: The response rate was 100%. Southeastern Brazil is the region where most of the CFCCs in the country are located (21 centers; 41%), followed by the southern and northeastern regions (11 centers each; 21.5%), the central-western region (6; 12%), and the northern region (2; 4%). A total of 4,371 patients with CF were cared for in Brazil during the study period, ranging from 7 to 240 patients per center (mean, 86 patients/center; median, 75 patients/center); 2,197 patients (50%) were cared for in centers in the southeastern region of the country, particularly in the state of São Paulo (33%), the remaining patients being treated in southern Brazil (1,014 patients, 23%), northeastern Brazil (665 patients, 15%), central-western Brazil (354 patients, 8%), and northern Brazil (141 patients, 4%). Overall, 47 centers (92%) reported having an incomplete multidisciplinary team; 4 (8%) lacked essential team members; 6 (12%) lacked a physical therapist; 5 (10%) lacked a dietitian; 17 (33%) lacked outpatient nursing care; 13 (25%) lacked outpatient social work services; 14 (27%) lacked a psychologist; and 32 (63%) lacked a clinical pharmacist. Seven CFCCs (14%) in the northern and northeastern regions of Brazil reported that the quality of newborn screening for CF was poor. All centers reported having difficulties in accessing CF medications.

CONCLUSIONS: Brazilian CFCCs experience multiple problems, including inadequate staffing, infrastructure, testing, and medication supply. There is an urgent need to regulate the implementation of CF referral centers and an appropriate network structure for the diagnosis and follow-up of CF patients using optimal treatment recommendations.

PMID:36753213 | DOI:10.36416/1806-3756/e20220306

Curr Opin Lipidol. 2023 Feb 2. doi: 10.1097/MOL.0000000000000866. Online ahead of print.

ABSTRACT

PURPOSE OF REVIEW: Not all patients with severe hypertriglyceridemia develop acute pancreatitis. We surveyed recent literature on inter-individual genetic variation in susceptibility to pancreatitis.

RECENT FINDINGS: Genetic determinants of pancreatitis include: rare Mendelian disorders caused by highly penetrant pathogenic variants in genes involved in trypsinogen activation; uncommon susceptibility variants in genes involved in trypsinogen activation, protein misfolding as well as calcium metabolism and cystic fibrosis, that have variable penetrance and show a range of odds ratios for pancreatitis; and common polymorphisms in many of the same genes that have only a small effect on risk. The role of these genetic variants in modulating pancreatitis risk in hypertriglyceridemia is unclear. However, among genetic determinants of plasma triglycerides, those predisposing to more severe hypertriglyceridemia associated with chylomicronemia appear to have higher pancreatitis risk.

SUMMARY: Currently, among patients with severe hypertriglyceridemia, the most consistent predictor of pancreatitis risk is the triglyceride level. Furthermore, pancreatitis risk appears to be modulated by a higher genetic burden of factors associated with greater magnitude of triglyceride elevation. The role of common and rare genetic determinants of pancreatitis itself in this metabolic context is unclear.

PMID:36752614 | DOI:10.1097/MOL.0000000000000866

Br J Radiol. 2023 Feb 8:20220630. doi: 10.1259/bjr.20220630. Online ahead of print.

ABSTRACT

The need for airway imaging is defined by the limited sensitivity of common clinical tests like spirometry, lung diffusion (DLCO) and blood gas analysis to early changes of peripheral airways and to inhomogeneous regional distribution of lung function deficits. Therefore, X-ray and computed tomography (CT) are frequently used to complement the standard tests.As an alternative, magnetic resonance imaging (MRI) offers radiation free lung imaging, but at lower spatial resolution. Non-contrast enhanced MRI shows healthy airways down to the first sub segmental level/4th order (CT: eighth). Bronchiectasis can be identified by wall thickening and fluid accumulation. Smaller airways become visible, when altered by peribronchiolar inflammation or mucus retention (tree-in-bud sign).The strength of MRI is functional imaging. Dynamic, time-resolvedMRI directly visualizesexpiratory airway collapse down to the lobar level (CT: segmental level). Obstruction of even smaller airways becomes visible as air trapping on the expiratory scans. MRI with hyperpolarized noble gases (3He, 129Xe) directly shows the large airways and peripheral lung ventilation. Dynamic contrast enhanced MRI (DCE MRI) indirectly shows airway dysfunction as perfusion deficits resulting from hypoxic vasoconstriction of the dependent lung volumes. Further promising scientific approaches such as non-contrast enhanced, ventilation-/perfusion-weighted MRI from periodic signal changes of respiration and blood flow are in development.In summary, MRI of the lungs and airways excels with its unique combination of morphologic and functional imaging capacities for research (e.g., in chronic obstructive lung disease or asthma) as well as for clinical imaging (e.g., in cystic fibrosis).

PMID:36752590 | DOI:10.1259/bjr.20220630

Org Biomol Chem. 2023 Feb 8. doi: 10.1039/d3ob00023k. Online ahead of print.

ABSTRACT

The pseudo-multicomponent reaction between propargyl amine, an aldehyde and an electron-deficient alkene is described. The C-H activation takes place thermally and allows the obtaining of cycloadducts in very good yields with high diastereoselectivities. The relative configuration is determined by X-ray diffraction analysis of the chiral molecule, obtained as a single diastereoisomer, using a chiral maleimide. A brief study of the stability of the possible ylides involved in the process is also mentioned, confirming the high diastereoselectivity observed. The high functional group density of these cycloadducts permits the synthesis of complex heterocycles. After allylation or propargylation of the pyrrolidine nitrogen atom, RCM-DA cycloaddition or cyclotrimerization with an alkyne is studied, respectively. In this last example, the resulting tetracyclic structures are of potential interest as drugs for the treatment of cystic fibrosis.

PMID:36752549 | DOI:10.1039/d3ob00023k

Pediatr Pulmonol. 2023 Feb 8. doi: 10.1002/ppul.26350. Online ahead of print.

ABSTRACT

To address health-inequalities, it is essential to consider CF in patients of non-European heritage when symptoms are suggestive. We recommend both sweat analysis and full CFTR gene analysis when initial/limited variant panels are negative. Mutation analysis is not only essential for accurate diagnosis but also impacts on the use of new modulator therapies that can reduce respiratory morbidity. The previous research focus on European/Caucasian populations has led to our current situation where knowledge on CFTR variants in African or Asian populations is scarce. This case has shown that the sequencing of the CFTR gene in patients of suspected CF of African origin can lead to the discovery of novel variants which will help expand our knowledge of variants in this genetically diverse population. This article is protected by copyright. All rights reserved.

PMID:36752109 | DOI:10.1002/ppul.26350

Skin Health Dis. 2022 Nov 25;3(1):e161. doi: 10.1002/ski2.161. eCollection 2023 Feb.

ABSTRACT

BACKGROUND: A high proportion of patients with Cystic Fibrosis (CF) also present the rare skin disease aquagenic palmoplantar keratoderma. A possible link between this condition and absence of a functional CF Transmembrane conductance Regulator protein in the sweat acinus and collecting duct remains unknown.

METHODS: In-depth characterization of sweat proteome profiles was performed in 25 CF patients compared to 12 healthy controls. A 20 μL sweat sample was collected after pilocarpine iontophoresis and liquid chromatography tandem mass spectrometry (LC-MS/MS) proteomic analysis was performed.

RESULTS: Sweat proteome profile of CF patients was significantly different from that of healthy subjects with 57 differentially expressed proteins. Cystic Fibrosis sweat proteome was characterized by an increase in 25 proteins including proteases (Kallikrein 7 and 13, Phospholipase B domain containing 1, Cathepsin A L2 and B, Lysosomal Pro-X carboxypeptidase); proinflammatory proteins (Annexin A2, Chitinase-3-like protein 1); cytochrome c and transglutaminases. Thirty-two proteins were downregulated in CF sweat including proteases (Elastase 2), antioxidative protein FAM129 B; membrane-bound transporter SLC6A14 and regulator protein Sodium-hydrogen antiporter 3 regulator 1.

CONCLUSION: This study is the first to report in-depth characterization of endogenous peptides in CF sweat and could help understand the complex physiology of the sweat gland. The proteome profile highlights the unbalanced proteolytic and proinflammatory activity of sweat in CF. These results also suggest a defect in pathways involved in skin barrier integrity in CF patients. Sweat proteome profile could prove to be a useful tool in the context of personalized medicine in CF.

PMID:36751320 | PMC:PMC9892418 | DOI:10.1002/ski2.161

Pediatr Pulmonol. 2023 Feb 7. doi: 10.1002/ppul.26346. Online ahead of print.

ABSTRACT

Nontuberculous mycobacteria (NTM) can cause severe chronic pulmonary infection, particularly in people with cystic fibrosis (CF). It is crucial for the laboratory to grow, identify to species and subspecies level, and report antimicrobial susceptibilities for the diagnosis and appropriate treatment of NTM. We suspected false negative acid-fast-bacilli (AFB) cultures or possibly reports of incorrect identification and/or antimicrobial susceptibility results from our local laboratories. We compared samples from our teaching hospital and commercial laboratories to a specialized NTM laboratory in 18 samples of sputum and/or bronchoalveolar lavage (BAL) fluid from patients with known or suspected NTM infection. We found discrepancies in all the samples that grew NTM at the specialized NTM laboratory compared to the local laboratories. These discrepancies are concerning. The commercial laboratories that are required to be used in the outpatient setting are mandated by insurance of the patient. We have no control over handling of samples in these laboratories. Our findings raise concerns about the accuracy of culture results in non-specialized laboratories, which is impacting patient care This article is protected by copyright. All rights reserved.

PMID:36751141 | DOI:10.1002/ppul.26346

Microbiology (Reading). 2022 Dec;168(12). doi: 10.1099/mic.0.001265.

ABSTRACT

Pseudomonas aeruginosa uses quorum sensing (QS) to coordinate the expression of multiple genes necessary for establishing and maintaining infection. It has previously been shown that lasR QS mutations frequently arise in cystic fibrosis (CF) lung infections, however, there has been far less emphasis on determining whether other QS system mutations arise during infection or in other environments. To test this, we utilized 852 publicly available sequenced P. aeruginosa genomes from the Pseudomonas International Consortium Database (IPCD) to study P. aeruginosa QS mutational signatures. To study isolates by source, we focused on a subset of 654 isolates collected from CF, wounds, and non-infection environmental isolates, where we could clearly identify their source. We also worked with a small collection of isolates in vitro to determine the impact of lasR and pqs mutations on isolate phenotypes. We found that lasR mutations are common across all environments and are not specific to infection nor a particular infection type. We also found that the pqs system proteins PqsA, PqsH, PqsL and MexT, a protein of increasing importance to the QS field, are highly variable. Conversely, RsaL, a negative transcriptional regulator of the las system, was found to be highly conserved, suggesting selective pressure to repress las system activity. Overall, our findings suggest that QS mutations in P. aeruginosa are common and not limited to the las system; however, LasR is unique in the frequency of putative loss-of-function mutations.

PMID:36748632 | DOI:10.1099/mic.0.001265

J Med Microbiol. 2022 Dec;71(12). doi: 10.1099/jmm.0.001611.

ABSTRACT

Introduction. Cystic fibrosis (CF) is a serious disease with multisystemic clinical signs that is easily and frequently complicated by bacterial infection. Recently, the prevalence of nontuberculous mycobacteria as secondary contaminants of CF has increased, with the Mycobacterium avium complex (MAC) and Mycobacterium abscessus complex (MABSC) being the most frequently identified. The MABSC includes subspecies of significant clinical importance, mainly due to their resistance to antibiotics.Gap statement. Sensitive method for early detection and differentiation of MABSC members and MAC complex for use in routine clinical laboratories is lacking. A method based on direct DNA isolation from sputum, using standard equipment in clinical laboratories and allowing uncovering of possible sample inhibition (false negative results) would be required. The availability of such a method would allow accurate and accelerated time detection of MABSC members and their timely and targeted treatment.Aim. To develop a real time multiplex assay for rapid and sensitive identification and discrimination of MABSC members and MAC complex.Methodology. The method of DNA isolation directly from the sputum of patients followed by quadruplex real-time quantitative PCR (qPCR) detection was developed and optimised. The sensitivity and limit of detection (LOD) of the qPCR was determined using human sputum samples artificially spiked with a known amount of M. abscessus subsp. massiliense (MAM).Results. The method can distinguish between MAC and MABSC members and, at the same time, to differentiate between M. abscessus subsp. abscessus/subsp. bolletii (MAAb/MAB) and MAM. The system was verified using 61 culture isolates and sputum samples from CF and non-CF patients showing 29.5 % MAAb/MAB, 14.7 % MAM and 26.2 % MAC. The LOD was determined to be 1 490 MAM cells in the sputum sample with the efficiency of DNA isolation being 95.4 %. Verification of the qPCR results with sequencing showed 100 % homology.Conclusions. The developed quadruplex qPCR assay, which is preceded by DNA extraction directly from patients' sputum without the need for culturing, significantly improves and speeds up the entire process of diagnosing CF patients and is therefore particularly suitable for use in routine laboratories.

PMID:36748608 | DOI:10.1099/jmm.0.001611

Microbiology (Reading). 2023 Jan;169(1). doi: 10.1099/mic.0.001271.

ABSTRACT

Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen frequently isolated from chronic infections of the cystic fibrosis lung and burn wounds, and is a major cause of antimicrobial-resistant nosocomial infections. P. aeruginosa is frequently co-isolated with the opportunistic fungal pathogen Candida albicans, with the presence of C. albicans in dual-species biofilms promoting tolerance to meropenem. Here, transcription profiling of mature P. aeruginosa single- or dual-species biofilms was carried out to understand the molecular mechanism(s) by which C. albicans enhances meropenem tolerance. C. albicans appeared to have a mild impact on the transcriptome of P. aeruginosa mature biofilms, with most differentially regulated genes being involved in interkingdom interactions (i.e. quorum sensing and phenazine biosynthesis). The addition of meropenem to mature single- or dual-species biofilms resulted in a significant bacterial transcriptional response, including the induction of the beta-lactamase, ampC, genes involved in biofilm formation. P. aeruginosa elicited a similar transcriptional response to meropenem in the presence of C. albicans, but C. albicans promoted the expression of additional efflux pumps, which could play roles in increasing the tolerance of P. aeruginosa to meropenem.

PMID:36748572 | DOI:10.1099/mic.0.001271

J Med Microbiol. 2022 Dec;72(12). doi: 10.1099/jmm.0.001617.

ABSTRACT

Introduction. Studying taxonomic and functional signatures of respiratory microbiomes provide a better understanding of airway diseases.Gap Statement. Several human airway metagenomics studies have identified taxonomic and functional features restricted to a single disease condition and the findings are not comparable across airway diseases due to use of different samples, NGS platforms, and bioinformatics databases and tools.Aim. To study the microbial taxonomic and functional components of sputum microbiome across airway diseases and healthy smokers.Methodology. Here, 57 whole metagenome shotgun sequencing (WMSS) runs coming from the sputum of five airway diseases: asthma, bronchiectasis, chronic obstructive pulmonary diseases (COPD), cystic fibrosis (CF), tuberculosis (TB), and healthy smokers as the control were reanalysed using a common WMSS analysis pipeline.Results. Shannon's index (alpha diversity) of the healthy smoker group was the highest among all. The beta diversity showed that the sputum microbiome is distinct in major airway diseases such as asthma, COPD and cystic fibrosis. The microbial composition based on differential analysis showed that there are specific markers for each airway disease like Acinetobacter bereziniae as a marker for COPD and Achromobacter xylosoxidans as a marker of cystic fibrosis. Pathways and metabolites identified from the sputum microbiome of these five diseases and healthy smokers also show specific markers. 'ppGpp biosynthesis' and 'purine ribonucleosides degradation' pathways were identified as differential markers for bronchiectasis and COPD. In this meta-analysis, besides bacteria kingdom, Aspergillus fumigatus was detected in asthma and COPD, and Roseolovirus human betaherpesvirus 7 was detected in COPD. Our analysis showed that the majority of the gene families specific to the drug-resistant associated genes were detected from opportunistic pathogens across all the groups.Conclusion. In summary, the specific species in the sputum of airway diseases along with the microbial features like specific gene families, pathways, and metabolites were identified which can be explored for better diagnosis and therapy.

PMID:36748565 | DOI:10.1099/jmm.0.001617

J Med Microbiol. 2022 Dec;71(12). doi: 10.1099/jmm.0.001643.

ABSTRACT

Chronic respiratory infection is the primary driver of mortality in individuals with cystic fibrosis (CF). Existing drug screening models utilised in preclinical antimicrobial development are unable to mimic the complex CF respiratory environment. Consequently, antimicrobials showing promising activity in preclinical models often fail to translate through to clinical efficacy in people with CF. Model systems used in CF anti-infective drug discovery and development range from antimicrobial susceptibility testing in nutrient broth, through to 2D and 3D in vitro tissue culture systems and in vivo models. No single model fully recapitulates every key aspect of the CF lung. To improve the outcomes of people with CF (PwCF) it is necessary to develop a set of preclinical models that collectively recapitulate the CF respiratory environment to a high degree of accuracy. Models must be validated for their ability to mimic aspects of the CF lung and associated lung infection, through evaluation of biomarkers that can also be assessed following treatment in the clinic. This will give preclinical models greater predictive power for identification of antimicrobials with clinical efficacy. The landscape of CF is changing, with the advent of modulator therapies that correct the function of the CFTR protein, while antivirulence drugs and phage therapy are emerging alternative treatments to chronic infection. This review discusses the challenges faced in current antimicrobial development pipelines, including the advantages and disadvantages of current preclinical models and the impact of emerging treatments.

PMID:36748497 | DOI:10.1099/jmm.0.001643

Microbiology (Reading). 2023 Jan;169(1). doi: 10.1099/mic.0.001290.

ABSTRACT

Cystic fibrosis (CF) is a genetic disorder affecting epithelial ion transport, which among other impacts results in defective mucociliary clearance and innate defenses in the respiratory tract. Consequently, people with CF experience lifelong infections of the respiratory mucosa that are chronic and polymicrobial in nature. Young children with CF are initially colonized by opportunists like nontypeable Haemophilus influenzae (NTHi), which normally resides within the microbiome of the nasopharynx and upper airways and can also cause infections of the respiratory mucosa that include bronchitis and otitis media. NTHi is typically supplanted by other microbes as patients age; for example, people with CF are often chronically infected with mucoid strains of Pseudomonas aeruginosa, which prior work in our laboratory has shown to promote colonization and persistence by other opportunists that include Stenotrophomonas maltophilia. Our previous work has shown that polymicrobial infection impacts host colonization and persistence of incoming microbes via diverse mechanisms that include priming of host immunity that can promote microbial clearance, and cooperativity within polymicrobial biofilms, which can promote persistence. In infection studies with BALB/c Cftrtm1UNC mice, results showed, as previously observed for WT BALB/c mice, preceding infection with NTHi decreased colonization and persistence by P. aeruginosa. Likewise, polymicrobial infection of BALB/c Cftrtm1UNC and C57BL/6 Cftrtm1UncTg(FABPhCFTR)1Jaw/J mice showed correlation between S. maltophilia and P. aeruginosa, with increased bacterial colonization and lung pathology. Based on these results, we conclude that our previous observations regarding polymicrobial infections with CF opportunists in WT mice are also validated using CF mice.

PMID:36748431 | DOI:10.1099/mic.0.001290

medRxiv. 2023 Jan 25:2023.01.22.23284619. doi: 10.1101/2023.01.22.23284619. Preprint.

ABSTRACT

Cystic fibrosis (CF) is a life-shortening genetic disorder, caused by mutations in the gene that encodes Cystic Fibrosis Transmembrane-conductance Regulator (CFTR), a cAMP-activated chloride and bicarbonate channel. Although multiple organ systems can be affected, CF lung disease claims the most morbidity and mortality due to chronic bacterial infection, persistent neutrophilic inflammation, and mucopurulent airway obstruction. Despite the clear predominance of neutrophils in these pathologies, how CFTR loss-of-function affects these cells per se remains incompletely understood. Here, we report the profiling and comparing of transcriptional signatures of peripheral blood neutrophils from CF participants and healthy human controls (HC) at the single-cell level. Circulating CF neutrophils had an aberrant basal state with significantly higher scores for activation, chemotaxis, immune signaling, and pattern recognition, suggesting that CF neutrophils in blood are prematurely primed. Such an abnormal basal state was also observed in neutrophils derived from an F508del-CF HL-60 cell line, indicating an innate characteristic of the phenotype. LPS stimulation drastically shifted the transcriptional landscape of HC circulating neutrophils towards a robust immune response, however, CF neutrophils were immune-exhausted. Moreover, CF blood neutrophils differed significantly from CF sputum neutrophils in gene programming with respect to neutrophil activation and aging, as well as inflammatory signaling, highlighting additional environmental influences on the neutrophils in CF lungs. Taken together, loss of CFTR function has intrinsic effects on neutrophil immune programming that leads to premature priming and dysregulated response to challenge.

PMID:36747678 | PMC:PMC9901053 | DOI:10.1101/2023.01.22.23284619

bioRxiv. 2023 Jan 27:2023.01.26.525796. doi: 10.1101/2023.01.26.525796. Preprint.

ABSTRACT

Multidrug-resistant Pseudomonas aeruginosa is a common nosocomial respiratory pathogen that continues to threaten the lives of mechanically-ventilated patients in intensive care units and those with underlying comorbidities such as cystic fibrosis or chronic obstructive pulmonary disease. For over 20 years, studies have repeatedly demonstrated that the major siderophore pyoverdine is an important virulence factor for P. aeruginosa in invertebrate and mammalian hosts in vivo . Despite its physiological significance, an in vitro , mammalian cell culture model to characterize the impact and the molecular mechanism of pyoverdine during infection has only recently been developed. In this study, we adapt a previously-established murine macrophage-based model for human bronchial epithelial cells. We demonstrate that pyoverdine-rich conditioned medium from P. aeruginosa disrupts epithelial integrity in a manner that depends on protease activity and the type II secretion system. Disrupting pyoverdine production, whether genetically or chemically, mitigates this damage. Interestingly, this damage did not require exotoxin A or PrpL (protease IV), two previously-characterized toxins regulated by pyoverdine. We also examined the effects of exposure to purified pyoverdine on lung epithelial cells. While pyoverdine accumulates within cells, the siderophore is largely sequestered inside early endosomes, showing little cytotoxicity. This is in contrast to other, more membrane-permeable iron chelators and siderophores such as pyochelin. However, pyoverdine may indirectly contribute to lung inflammation by potentiating these iron chelators in promoting the production of proinflammatory cytokines.

PMID:36747656 | PMC:PMC9901015 | DOI:10.1101/2023.01.26.525796

Pediatr Pulmonol. 2023 Feb 6. doi: 10.1002/ppul.26344. Online ahead of print.

ABSTRACT

BACKGROUND: A collaboration between the University of Michigan (UM) Cystic Fibrosis Center (CFC) and Marmara University (MU) CFC was initiated in MU through conducting Quality Improvement projects (QIP). The global aim was to improve nutritional status of children with CF (cwCF), with a specific aim to increase the mean BMI percentile (BMIp) for cwCF by 10 percentile points in 12 months.

METHODS: BMI percentiles of cwCF were categorized as: nutritionally adequate (BMIp ≥ 50%); at risk (BMIp 25-49%); urgently at risk (BMIp 10-25%); critically at risk (BMIp < 10%). Appropriate interventions were made according to BMIp category every three months. Forced expiratory volume in one second percent predicted (FEV1pp), and health-related quality of life (HRQoL) were evaluated.

RESULTS: 182 cwCF with a mean age of 9.1 ± 4.3 years were included in the project. Baseline BMIp increased from 25.6 to 37.2 at the 12th month (p<0.001). In the critically at risk group BMIp increased from 3.6 to 20.5 (p< 0.001), in the urgently at risk group from 15.9 to 30.8 (p< 0.001), in the at risk group from 37.0 to 44.2 (p< 0.079) and in the nutritionally adequate group the increase was from 66.8 to 69.5 (p< 0.301). FEV1pp also improved significantly, from 81.3±20.6 to 85.9±20.8 (p<0.001). Physical functioning, eating problems and respiratory symptoms domains of the HRQoL evaluation improved (p<0.05).

CONCLUSION: This project has led to significant improvements in BMIp, FEV1pp and HRQoL of cwCF; similar projects could easily be implemented by centers in other developing countries. This article is protected by copyright. All rights reserved.

PMID:36747482 | DOI:10.1002/ppul.26344