Vaccines (Basel). 2024 Mar 15;12(3):313. doi: 10.3390/vaccines12030313.

ABSTRACT

Burkholderia are a group of Gram-negative bacteria that can cause a variety of diseases in at-risk populations. B. pseudomallei and B. mallei, the etiological agents of melioidosis and glanders, respectively, are the two clinically relevant members of the B. pseudomallei complex (Bpc). The development of vaccines against Bpc species has been accelerated in recent years, resulting in numerous promising subunits and glycoconjugate vaccines incorporating a variety of antigens. However, a second group of pathogenic Burkholderia species exists known as the Burkholderia cepacia complex (Bcc), a group of opportunistic bacteria which tend to affect individuals with weakened immunity or cystic fibrosis. To date, there have been few attempts to develop vaccines to Bcc species. Therefore, the primary goal of this review is to provide a broad overview of the various subunit antigens that have been tested in Bpc species, their protective efficacy, study limitations, and known or suspected mechanisms of protection. Then, we assess the reviewed Bpc antigens for their amino acid sequence conservation to homologous proteins found in Bcc species. We propose that protective Bpc antigens with a high degree of Bpc-to-Bcc sequence conservation could serve as components of a pan-Burkholderia vaccine capable of protecting against both disease-causing groups.

PMID:38543947 | DOI:10.3390/vaccines12030313

Pharmaceutics. 2024 Mar 1;16(3):347. doi: 10.3390/pharmaceutics16030347.

ABSTRACT

Nowadays, the interest in research towards the local administration of drugs via the inhalation route is growing as it enables the direct targeting of the lung tissue, at the same time reducing systemic side effects. This is of great significance in the era of nucleic acid therapeutics and personalized medicine for the local treatment of severe lung diseases. However, the success of any inhalation therapy is driven by a delicate interplay of factors, such as the physiochemical profile of the payload, formulation, inhalation device, aerodynamic properties, and interaction with the lung fluids. The development of drug delivery systems tailored to the needs of this administration route is central to its success and to revolutionize the treatment of respiratory diseases. With this review, we aim to provide an up-to-date overview of advances in the development of nanoparticulate carriers for drug delivery to the lung tissue, with special regard concerning lipid and polymer-based nanocarriers (NCs). Starting from the biological barriers that the anatomical structure of the lung imposes, and that need to be overcome, the current strategies to achieve efficient lung delivery and the best support for the success of NCs for inhalation are highlighted.

PMID:38543241 | DOI:10.3390/pharmaceutics16030347

Pharmaceuticals (Basel). 2024 Mar 15;17(3):376. doi: 10.3390/ph17030376.

ABSTRACT

To meet the urgent need for new antibacterial molecules, a small library of pyrazolyl thioureas (PTUs) was designed, synthesized and tested against difficult-to-treat human pathogens. The prepared derivatives are characterized by a carboxyethyl functionality on C4 and different hydroxyalkyl chains on N1. Compounds 1a-o were first evaluated against a large panel of Gram-positive and Gram-negative pathogens. In particular, the majority of PTUs proved to be active against different species of the Staphylococcus genus, with MIC values ranging from 32 to 128 µg/mL on methicillin-resistant Staphylococcus strains, often responsible for severe pulmonary disease in cystic fibrosis patients. Time-killing experiments were also performed for the most active compounds, evidencing a bacteriostatic mechanism of action. For most active derivatives, cytotoxicity was evaluated in Vero cells, and at the tested concentrations and at the experimental exposure time of 24 h, none of the compounds analysed showed significant toxicity. In addition, favourable drug-like, pharmacokinetic and toxicity properties were predicted for all new synthesized derivatives. Overall, the collected data confirmed the PTU scaffold as a promising chemotype for the development of novel antibacterial agents active against Gram-positive multi-resistant strains frequently isolated from cystic fibrosis patients.

PMID:38543162 | DOI:10.3390/ph17030376

Pharmaceuticals (Basel). 2024 Mar 12;17(3):367. doi: 10.3390/ph17030367.

ABSTRACT

Patients with cystic fibrosis (PwCF) have recently experienced an unprecedented breakthrough with the adoption of modulator therapy in clinical practice. This remarkable achievement has led to the reconsideration of disease management as the increased life expectancy has gradually shifted the attention over a spectrum of extra-pulmonary manifestations that become prevalent in the aging population. It comes to be that complementary approaches that target patient co-morbidities are needed for the optimal clinical management of PwCF. A strategy would be to adjuvate the cystic fibrosis transmembrane conductance regulator (CFTR) in performing its functions in the different organs in which it is expressed. Solute carrier family 26 (SLC26) members appear ideal in this context. Indeed, they not only cooperate with CFTR in the organ-dependent regulation of ion fluxes but physically interact with it to reciprocally modulate their function. In this opinion, we summarize available evidence pointing to a physical and functional interaction between CFTR and SLC26 members, with a particular focus on SLC26A6 for its wider expression and broader anion selectivity, and then discuss how restoring the physical interaction between CFTR and SLC26A6 might be beneficial in the treatment of PwCF in the era of modulator therapy.

PMID:38543153 | DOI:10.3390/ph17030367

Int J Mol Sci. 2024 Mar 16;25(6):3384. doi: 10.3390/ijms25063384.

ABSTRACT

Cystic fibrosis (CF) is a fatal autosomal recessive disorder caused by the loss of function mutations within a single gene for the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). CFTR is a chloride channel that regulates ion and fluid transport across various epithelia. The discovery of CFTR as the CF gene and its cloning in 1989, coupled with extensive research that went into the understanding of the underlying biological mechanisms of CF, have led to the development of revolutionary therapies in CF that we see today. The highly effective modulator therapies have increased the survival rates of CF patients and shifted the epidemiological landscape and disease prognosis. However, the differential effect of modulators among CF patients and the presence of non-responders and ineligible patients underscore the need to develop specialized and customized therapies for a significant number of patients. Recent advances in the understanding of the CFTR structure, its expression, and defined cellular compositions will aid in developing more precise therapies. As the lifespan of CF patients continues to increase, it is becoming critical to clinically address the extra-pulmonary manifestations of CF disease to improve the quality of life of the patients. In-depth analysis of the molecular signature of different CF organs at the transcriptional and post-transcriptional levels is rapidly advancing and will help address the etiological causes and variability of CF among patients and develop precision medicine in CF. In this review, we will provide an overview of CF disease, leading to the discovery and characterization of CFTR and the development of CFTR modulators. The later sections of the review will delve into the key findings derived from single-molecule and single-cell-level analyses of CFTR, followed by an exploration of disease-relevant protein complexes of CFTR that may ultimately define the etiological course of CF disease.

PMID:38542363 | DOI:10.3390/ijms25063384

J Clin Med. 2024 Mar 16;13(6):1711. doi: 10.3390/jcm13061711.

ABSTRACT

The phenomenon of antimicrobial resistance (AMR) is a critical global health challenge, with prospects indicating its potential to become the leading cause of death worldwide in the coming years. Individuals with pre-existing conditions, such as neoplastic disease undergoing chemotherapy, those on immunosuppressive therapy, and individuals with rare diseases like cystic fibrosis (CF), face heightened challenges due to AMR. CF is a rare disease caused by a deficiency in the synthesis of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) channel protein, resulting in multi-organ clinical symptoms, particularly in the respiratory system. PwCF experience recurrent pulmonary exacerbations triggered by bacterial or viral infections, making them particularly vulnerable to the impact of AMR. This review delves into the complex relationship between AMR and climate dynamics, focusing on the unique challenges faced by individuals with CF. It discusses the methods employed to measure AMR, its global impact on antibiotic resistance, and the specific microbial communities present in the CF airway. The review also explores the intricacies of antimicrobial resistance within the context of cystic fibrosis, emphasizing the urgent need for research in this field.

PMID:38541936 | DOI:10.3390/jcm13061711

J Clin Med. 2024 Mar 13;13(6):1650. doi: 10.3390/jcm13061650.

ABSTRACT

(1) Background: The introduction of highly effective CFTR-modulating therapies (HEMT) has changed the course of the disease for many people with Cystic Fibrosis (pwCF). Attention previously focused on life-threatening conditions of the respiratory system has broadened, bringing the involvement of the digestive system into the clinical and scientific focus. This emphasized the need for sensitive tools to capture and quantify changes in abdominal symptoms (AS), ideally applying patient-reported outcome measures (PROMs). (2) Methods: The present review focuses on studies addressing AS assessment deriving from the multi-organic abdominal involvement in pwCF. Among 5224 publications retrieved until Nov. 2022, 88 were eligible, and 39 were finally included. (3) Results: The review reveals that for a long time, especially before HEMT availability, AS in pwCF were assessed by single questions on abdominal complaints or non-validated questionnaires. PROMs focusing on quality of life (QOL) including a few GI-related questions were applied. Likewise, PROMs developed and partially validated for other non-CF GI pathologies, such as chronic inflammatory bowel diseases, irritable bowel syndrome, gastroesophageal reflux, constipation, or pancreatitis, were implemented. (4) Conclusions: Only lately, CF-specific GI-PROMs have been developed and validated following FDA guidelines, showing high sensitivity to changes and capturing marked and statistically significant reductions in the burden of AS achieved with HEMT implementation.

PMID:38541878 | DOI:10.3390/jcm13061650

J Clin Med. 2024 Mar 12;13(6):1621. doi: 10.3390/jcm13061621.

ABSTRACT

Chronic obstructive pulmonary disease (COPD) is often part of a more complex cardiopulmonary disease, especially in older patients. The differential diagnosis of the acute exacerbation of COPD and/or heart failure (HF) in emergency settings is challenging due to their frequent coexistence and symptom overlap. Both conditions have a detrimental impact on each other's prognosis, leading to increased mortality rates. The timely diagnosis and treatment of COPD and coexisting factors like left ventricular overload or HF in inpatient and outpatient care can improve prognosis, quality of life, and long-term outcomes, helping to avoid exacerbations and hospitalization, which increase future exacerbation risk. This work aims to address existing gaps, providing management recommendations for COPD with/without HF, particularly when both conditions coexist. During virtual meetings, a panel of experts (the authors) discussed and reached a consensus on the differential and paired diagnosis of COPD and HF, providing suggestions for risk stratification, accurate diagnosis, and appropriate therapy for inpatients and outpatients. They emphasize that when COPD and HF are concomitant, both conditions should receive adequate treatment and that recommended HF treatments are not contraindicated in COPD and have favorable effects. Accurate diagnosis and therapy is crucial for effective treatment, reducing hospital readmissions and associated costs. The management considerations discussed in this study can potentially be extended to address other cardiopulmonary challenges frequently encountered by COPD patients.

PMID:38541845 | DOI:10.3390/jcm13061621

Medicina (Kaunas). 2024 Mar 14;60(3):477. doi: 10.3390/medicina60030477.

ABSTRACT

Cystic fibrosis-related diabetes (CFRD) is the most common comorbidity in patients with cystic fibrosis (CF). CFRD has been correlated with important clinical outcomes, including poor nutrition, reduced pulmonary function, and earlier mortality. However, clinical decline due to abnormalities of blood glucose (dysglycemia) begins early in CF, before the diagnosis of CFRD by the gold-standard oral glucose tolerance test (OGTT). Continuous glucose monitoring (CGM) has been validated in patients with CF and has been recognized as a valuable tool in detecting early glucose abnormalities in patients with CF. Several CGM parameters have been used to predict CFRD in some but not all studies, and there is no consensus regarding CGM use for diagnostic purposes. Thus, it remains a complementary test to OGTT in CFRD diagnosis. The aim of this review is to provide an update on the pathophysiological mechanisms of CFRD, recent advances in the use of CGM for CFRD screening, and the association between CGM measures and CF-related clinical outcomes.

PMID:38541202 | DOI:10.3390/medicina60030477

Antioxidants (Basel). 2024 Mar 18;13(3):368. doi: 10.3390/antiox13030368.

ABSTRACT

Progressive respiratory airway destruction due to unresolved inflammation induced by periodic infectious exacerbation episodes is a hallmark of cystic fibrosis (CF) lung pathology. To clear bacteria, neutrophils release high amounts of reactive oxygen species (ROS), which inflict collateral damage to the neighboring epithelial cells causing oxidative stress. A former genome-wide small interfering RNA (siRNA) screening in CF submucosal gland cells, instrumental for mucociliary clearance, proposed tumor necrosis factor receptor superfamily member 1B (TNFRSF1B; TNFR2) as a potential hit involved in oxidative stress susceptibility. Here, we demonstrate the relevance of TNFRSF1B transcript knock-down for epithelial cell protection under strong oxidative stress conditions. Moreover, a blockade of TNFR signaling through its ligand lymphotoxin-α (LTA), overexpressed in airway epithelial cells under oxidative stress conditions, using the anti-tumor necrosis factor (TNF) biologic etanercept significantly increased the viability of these cells from a toxic oxidizing agent. Furthermore, bioinformatic analyses considering our previous RNA interference (RNAi) screening output highlight the relevance of TNFRSF1B and of other genes within the TNF pathway leading to epithelial cell death. Thus, the inhibition of the LTα3-TNFR2 axis could represent a useful therapeutic strategy to protect the respiratory airway epithelial lining from the oxidative stress challenge because of recurrent infection/inflammation cycles faced by CF patients.

PMID:38539900 | DOI:10.3390/antiox13030368

Children (Basel). 2024 Mar 8;11(3):321. doi: 10.3390/children11030321.

ABSTRACT

The prevalence of scoliosis in people with cystic fibrosis (CF) seems to be greater than in the normal population. Over the last two years, a screening for spinal deformities was carried out in patients with CF aged 5 to 18 years, followed up at the CF regional Centre in Parma (Italy). Forty-three patients (twenty-seven males, mean age: 11.8 ± 4.5 years) were enrolled in the study. Nine patients (20.9%) were diagnosed with scoliosis, with a mean Cobb angle of 20.8 ± 9.4 (12-38°). Five patients (11.6%) were diagnosed with a postural kyphosis attitude and one with pathological fixed kyphosis. All patients with scoliosis and postural kyphosis started daily physiotherapeutic scoliosis-specific exercises (PSSE). Compared to people without CF, the prevalence of scoliosis in our paediatric CF population seems to be higher and more present in males; the curves were thoracic and mostly right-sided. CF disease, hyposthenic postural attitude and sedentary lifestyle can contribute to the pathogenesis of this musculoskeletal alteration. Spinal deformities may negatively affect pulmonary function, resulting in disability, pain and a decreased quality of life. Since the prevention of musculoskeletal deformities is easier than restoration, in CF population targeted screening during growth and interventions, including regular physical exercise, are mandatory.

PMID:38539357 | DOI:10.3390/children11030321

Paediatr Respir Rev. 2024 Feb 16:S1526-0542(24)00017-4. doi: 10.1016/j.prrv.2024.02.001. Online ahead of print.

ABSTRACT

The advent of next generation sequencing has rapidly challenged the paediatric respiratory physician's understanding of lung microbiology and the role of the lung microbiome in host health and disease. In particular, the role of "microbial key players" in paediatric respiratory disease is yet to be fully explained. Accurate profiling of the lung microbiome in children is challenging since the ability to obtain lower airway samples coupled with processing "low-biomass specimens" are both technically difficult. Many studies provide conflicting results. Early microbiota-host relationships may be predictive of the development of chronic respiratory disease but attempts to correlate lower airway microbiota in premature infants and risk of developing bronchopulmonary dysplasia (BPD) have produced mixed results. There are differences in lung microbiota in asthma and cystic fibrosis (CF). The increased abundance of oral taxa in the lungs may (or may not) promote disease processes in asthma and CF. In CF, correlation between microbiota diversity and respiratory decline is commonly observed. When one considers other pathogens beyond the bacterial kingdom, the contribution and interplay of fungi and viruses within the lung microbiome further increase complexity. Similarly, the interaction between microbial communities in different body sites, such as the gut-lung axis, and the influence of environmental factors, including diet, make the co-existence of host and microbes ever more complicated. Future, multi-omics approaches may help uncover novel microbiome-based biomarkers and therapeutic targets in respiratory disease and explain how we can live in harmony with our microbial companions.

PMID:38538377 | DOI:10.1016/j.prrv.2024.02.001

Auris Nasus Larynx. 2024 Mar 26;51(3):553-568. doi: 10.1016/j.anl.2024.02.001. Online ahead of print.

ABSTRACT

OBJECTIVE: Primary ciliary dyskinesia (PCD) is a relatively rare genetic disorder that affects approximately 1 in 20,000 people. Approximately 50 genes are currently known to cause PCD. In light of differences in causative genes and the medical system in Japan compared with other countries, a practical guide was needed for the diagnosis and management of Japanese PCD patients.

METHODS: An ad hoc academic committee was organized under the Japanese Rhinologic Society to produce a practical guide, with participation by committee members from several academic societies in Japan. The practical guide including diagnostic criteria for PCD was approved by the Japanese Rhinologic Society, Japanese Society of Otolaryngology-Head and Neck Surgery, Japanese Respiratory Society, and Japanese Society of Pediatric Pulmonology.

RESULTS: The diagnostic criteria for PCD consist of six clinical features, six laboratory findings, differential diagnosis, and genetic testing. The diagnosis of PCD is categorized as definite, probable, or possible PCD based on a combination of the four items above. Diagnosis of definite PCD requires exclusion of cystic fibrosis and primary immunodeficiency, at least one of the six clinical features, and a positive result for at least one of the following: (1) Class 1 defect on electron microscopy of cilia, (2) pathogenic or likely pathogenic variants in a PCD-related gene, or (3) impairment of ciliary motility that can be repaired by correcting the causative gene variants in iPS cells established from the patient's peripheral blood cells.

CONCLUSION: This practical guide provides clinicians with useful information for the diagnosis and management of PCD in Japan.

PMID:38537559 | DOI:10.1016/j.anl.2024.02.001

Hepatology. 2024 Mar 27. doi: 10.1097/HEP.0000000000000863. Online ahead of print.

ABSTRACT

BACKGROUND AND AIMS: It is not known why severe cystic fibrosis (CF) liver disease (CFLD) with portal hypertension occurs in only ~7% of people with CF (pwCF). We aimed to identify genetic modifiers for severe CFLD to improve understanding of disease mechanisms.

APPROACH AND RESULTS: Whole genome sequencing was available in 4,082 pwCF with pancreatic insufficiency (n=516 with severe CFLD; n=3,566 without CFLD). We tested ~15.9 million SNPs for association with severe CFLD versus no-CFLD, using pre-modulator clinical phenotypes including: 1) genetic variant (SERPINA1; Z-allele) previously associated with severe CFLD; 2) candidate SNPs (n=205) associated with non-CF liver diseases; 3) genome-wide association study (GWAS) of common/rare SNPs; 4) transcriptome-wide association (TWAS); and 5) gene-level and pathway analyses. The Z-allele was significantly associated with severe CFLD (p=1.1×10-4). No significant candidate SNPs were identified. GWAS identified genome-wide significant SNPs in 2 loci and 2 suggestive loci. These 4 loci contained genes [significant, PKD1 (p=8.05×10-10) and FNBP1 (p=4.74×10-9); suggestive, DUSP6 (p=1.51×10-7) and ANKUB1 (p=4.69×10-7)] relevant to severe CFLD pathophysiology. TWAS identified 3 genes [CXCR1 (p=1.01×10-6), AAMP (p=1.07×10-6), and TRBV24 (p=1.23×10-5)] involved in hepatic inflammation and innate immunity. Gene-ranked analyses identified pathways enriched in genes linked to multiple liver pathologies.

CONCLUSION: These results identify loci/genes associated with severe CFLD that point to disease mechanisms involving hepatic fibrosis, inflammation and innate immune function, vascular pathology, intracellular signaling, actin cytoskeleton and tight junction integrity, and mechanisms of hepatic steatosis and insulin resistance. These discoveries will facilitate mechanistic studies and the development of therapeutics for severe CFLD.

PMID:38536042 | DOI:10.1097/HEP.0000000000000863

Cells. 2024 Mar 16;13(6):524. doi: 10.3390/cells13060524.

ABSTRACT

We report a novel RPGR missense variant co-segregated with a familial X-linked retinitis pigmentosa (XLRP) case. The brothers were hemizygous for this variant, but only the proband presented with primary ciliary dyskinesia (PCD). Thus, we aimed to elucidate the role of the RPGR variant and other modifier genes in the phenotypic variability observed in the family and its impact on motile cilia. The pathogenicity of the variant on the RPGR protein was evaluated by in vitro studies transiently transfecting the mutated RPGR gene, and immunofluorescence analysis on nasal brushing samples. Whole-exome sequencing was conducted to identify potential modifier variants. In vitro studies showed that the mutated RPGR protein could not localise to the cilium and impaired cilium formation. Accordingly, RPGR was abnormally distributed in the siblings' nasal brushing samples. In addition, a missense variant in CEP290 was identified. The concurrent RPGR variant influenced ciliary mislocalisation of the protein. We provide a comprehensive characterisation of motile cilia in this XLRP family, with only the proband presenting PCD symptoms. The variant's pathogenicity was confirmed, although it alone does not explain the respiratory symptoms. Finally, the CEP290 gene may be a potential modifier for respiratory symptoms in patients with RPGR mutations.

PMID:38534367 | DOI:10.3390/cells13060524

Front Pharmacol. 2024 Mar 12;15:1386077. doi: 10.3389/fphar.2024.1386077. eCollection 2024.

NO ABSTRACT

PMID:38533259 | PMC:PMC10964944 | DOI:10.3389/fphar.2024.1386077

Lab Anim Res. 2024 Mar 26;40(1):10. doi: 10.1186/s42826-024-00197-4.

ABSTRACT

The ferret (Mustela putorius furo) is a small domesticated species of the family Mustelidae within the order Carnivora. The present article reviews and discusses the current state of knowledge about housing, care, breeding, and biomedical uses of ferrets. The management and breeding procedures of ferrets resemble those used for other carnivores. Understanding its behavior helps in the use of environmental enrichment and social housing, which promote behaviors typical of the species. Ferrets have been used in research since the beginning of the twentieth century. It is a suitable non-rodent model in biomedical research because of its hardy nature, social behavior, diet and other habits, small size, and thus the requirement of a relatively low amount of test compounds and early sexual maturity compared with dogs and non-human primates. Ferrets and humans have numerous similar anatomical, metabolic, and physiological characteristics, including the endocrine, respiratory, auditory, gastrointestinal, and immunological systems. It is one of the emerging animal models used in studies such as influenza and other infectious respiratory diseases, cystic fibrosis, lung cancer, cardiac research, gastrointestinal disorders, neuroscience, and toxicological studies. Ferrets are vulnerable to many human pathogenic organisms, like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), because air transmission of this virus between them has been observed in the laboratory. Ferrets draw the attention of the medical community compared to rodents because they occupy a distinct niche in biomedical studies, although they possess a small representation in laboratory research.

PMID:38532510 | DOI:10.1186/s42826-024-00197-4

Am J Respir Cell Mol Biol. 2024 Mar 26. doi: 10.1165/rcmb.2023-0408OC. Online ahead of print.

ABSTRACT

Epithelial polarity is fundamental in maintaining barrier integrity and tissue protection. In cystic fibrosis (CF), apicobasal polarity of the airway epithelium is altered, resulting in increased apical fibronectin deposition and enhanced susceptibility to bacterial infections. Here, we evaluated the effect of highly effective modulator treatment (HEMT) on fibronectin apical deposition and investigated the intracellular mechanisms triggering the defect in polarity of the CF airway epithelium. To this end, primary cultures of CF (F508del variant) human airway epithelial cells (HAECs) and a HAEC line, Calu-3, knocked-down (KD) for CFTR (CFTR KD) were compared to control counterparts, grown at an air-liquid interface (ALI). We show that CFTR mutation in primary HAECs and CFTR KD cells promote the overexpression and over-secretion of TGF-β1 and DKK1 when cultured at ALI. These dynamic changes result in hyperactivation of the TGF-β pathway and inhibition of the Wnt pathway through degradation of β-catenin leading to imbalanced proliferation and polarization. The abnormal interplay between TGF-β and Wnt signaling pathways is reinforced by aberrant Akt signaling. Pharmacological manipulation of TGF-β, Wnt, and Akt pathways restored polarization of the F508del CF epithelium, a correction that was not achieved by HEMT. Our data shed new insights into the signaling pathways that fine-tune apicobasal polarization in primary airway epithelial cells and may provide an explanation to the mitigated efficacy of HEMT on lung infection in people with CF.

PMID:38531016 | DOI:10.1165/rcmb.2023-0408OC

Rhinology. 2024 Mar 26. doi: 10.4193/Rhin23.487. Online ahead of print.

ABSTRACT

BACKGROUND: The introduction of CFTR modulators has changed the landscape in the treatment of cystic fibrosis (CF) and early case series have shown improvements in sinonasal outcomes in this patient population.

METHODOLOGY: A real-word data study was performed to evaluate the impact of dual therapy with tezacaftor/ivacaftor (TEZ/IVA) and triple therapy with elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) on CF-related chronic rhinosinusitis (CRS), by comparing subjective and objective outcome measures at baseline, 12 months after treatment with TEZ/IVA and six months after treatment with ELX/TEZ/IVA.

RESULTS: In total, 43 CF patients, with a mean age of 32 years, were included. After triple therapy, significant improvements in overall visual analogue scale, SNOT-22, Lund Kennedy, nasal polyps, and Lund-Mackay scores were observed, whereas no beneficial effect could be seen in patients treated with dual therapy. Bacterial upper airway colonization did not differ pre- and postmodulator therapy in the present study. The number of responders to dual and triple therapy is 23.8% and 63.2% of the patients, respectively.

CONCLUSIONS: Triple therapy with ELX/TEZ/IVA is superior to dual therapy with TEZ/IVA in the treatment of CF-CRS, as significantly reduced sinonasal complaints, nasal endoscopy and CT scores were observed after triple therapy, whereas this was not the case for dual therapy.

PMID:38530204 | DOI:10.4193/Rhin23.487

mSystems. 2024 Mar 26:e0116523. doi: 10.1128/msystems.01165-23. Online ahead of print.

ABSTRACT

To establish infections in human hosts, Pseudomonas aeruginosa must overcome innate immune-generated oxidative stress, such as the hypochlorous acid (HOCl) produced by neutrophils. We set out to find specific biomarkers of oxidative stress through the development of a protocol for the metabolic profiling of P. aeruginosa cultures grown in the presence of different oxidants using a novel ionization technique for mass spectrometry, laser desorption rapid evaporative ionization mass spectrometry (LD-REIMS). We demonstrated the ability of LD-REIMS to classify samples as untreated or treated with a specific oxidant with 100% accuracy and identified a panel of 54 metabolites with significantly altered concentrations after exposure to one or more of the oxidants. Key metabolic changes were conserved in P. aeruginosa clinical strains isolated from patients with cystic fibrosis lung infections. These data demonstrated that HOCl stress impacted the Pseudomonas quinolone signal (PQS) quorum sensing system. Ten 2-alkyl-4-quinolones (AHQs) associated with the PQS system were significantly lower in concentration in HOCl-stressed P. aeruginosa cultures, including 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS), the most active signal molecule of the PQS system. The PQS system regulates the production of virulence factors, including pyocyanin and elastase, and their levels were markedly affected by HOCl stress. No pyocyanin was detectable and elastase concentrations were reduced by more than 75% in cultures grown with sub-lethal concentrations of HOCl, suggesting that this neutrophil-derived oxidant may disrupt the ability of P. aeruginosa to establish infections through interference with production of PQS-associated virulence factors.

IMPORTANCE: This work demonstrates that a high-throughput ambient ionization mass spectrometry method can be used successfully to study a bacterial stress response. Its application to the opportunistic pathogen Pseudomonas aeruginosa led to the identification of specific oxidative stress biomarkers, and demonstrated that hypochlorous acid, an oxidant specifically produced by human neutrophils during infection, affects quorum sensing and reduces production of the virulence factors pyocyanin and elastase. No pyocyanin was detectable and elastase levels were reduced by more than 75% in bacteria grown in the presence of hypochlorous acid. This approach has the potential to be widely applicable to the characterization of the stress responses of bacteria.

PMID:38530056 | DOI:10.1128/msystems.01165-23