Cystic Fibrosis

Durable transgene expression and efficient re-administration after rAAV2.5T-mediated fCFTRΔR gene delivery to adult ferret lungs

Fri, 2024-04-19 06:00

Mol Ther Methods Clin Dev. 2024 Mar 28;32(2):101244. doi: 10.1016/j.omtm.2024.101244. eCollection 2024 Jun 13.

ABSTRACT

The dosing interval for effective recombinant adeno-associated virus (rAAV)-mediated gene therapy of cystic fibrosis lung disease remains unknown. Here, we assessed the durability of rAAV2.5T-fCFTRΔR-mediated transgene expression and neutralizing antibody (NAb) responses in lungs of adult wild-type ferrets. Within the first 3 months following rAAV2.5T-fCFTRΔR delivery to the lung, CFTRΔR transgene expression declined ∼5.6-fold and then remained stable to 5 months at ∼26% the level of endogenous CFTR. rAAV NAbs in the plasma and bronchoalveolar lavage fluid (BALF) peaked at 21 days, coinciding with peak ELISpot T cell responses to AAV capsid peptides, after which both responses declined and remained stable at 4-5 months post dosing. Administration of reporter vector rAAV2.5T-gLuc (gaussia luciferase) at 5 months following rAAV2.5T-fCFTRΔR dosing gave rise to similar levels of gLuc expression in the BALF as observed in age-matched reporter-only controls, demonstrating that residual BALF NAbs were functionally insignificant. Notably, the second vector administration led to a 2.6-fold greater ELISpot T cell response and ∼2.3-fold decline in fCFTRΔR mRNA and vector genomes derived from the initial rAAV2.5T-fCFTRΔR administration, suggesting selective destruction of transduced cells from the first vector dose. These findings provide insights into humoral and cellular immune response to rAAV that may be useful for optimizing gene therapy to the cystic fibrosis lung.

PMID:38638546 | PMC:PMC11024656 | DOI:10.1016/j.omtm.2024.101244

Categories: Literature Watch

"We'll deal with it as it comes": A Qualitative Analysis of Romantic Partners' Dyadic Coping in Cystic Fibrosis

Fri, 2024-04-19 06:00

J Soc Pers Relat. 2024 Apr;41(4):689-705. doi: 10.1177/02654075231190617. Epub 2023 Jul 21.

ABSTRACT

BACKGROUND: Although cystic fibrosis (CF) is a progressive, life-limiting, genetic disease, recent advances have extended survival, allowing persons with CF the time and physical and mental health to form romantic relationships. Previous studies have shown the importance of dyadic coping to positive psychosocial functioning and relationship satisfaction for people with serious chronic illness and their romantic partners, but little work has been done with persons with CF and their partners. The present study examines dyadic coping processes in persons with CF and their romantic partners.

METHODS: Sixteen adults with moderate to severe CF (Mage=42.3, 43.8% identified as cisgender male, 56.2% identified as cisgender female) and their romantic partners (Mage=43.8, 56.3% identified as cisgender male, 43.7% identified as cisgender female) participated in individual semi-structured interviews focused on topics related to quality of life, communication, and palliative care. We conducted a directed content analysis utilizing Berg and Upchurch's (2007) developmental-contextual theoretical model to examine dyadic coping processes in persons with CF and their romantic partners.

RESULTS: Consistent with the developmental-contextual model of dyadic coping, couples described adapting to health and functional declines that occurred over time. Dyads were aligned in their appraisals of illness representation, illness ownership, and perspectives of illness as a shared stressor; they used shared coping mechanisms that included supportive and collaborative actions rather than uninvolved or controlling strategies.

CONCLUSIONS: We recommend family-based approaches to medical decision-making and goals of care conversations with persons with CF and their partners, aligning those approaches with supportive and collaborative coping configurations. This may improve psychosocial outcomes for patients and their partners.

PMID:38638205 | PMC:PMC11025702 | DOI:10.1177/02654075231190617

Categories: Literature Watch

Newborn screening in France: news and perspectives

Fri, 2024-04-19 06:00

Ann Biol Clin (Paris). 2024 Feb 1;82(1):24-31. doi: 10.1684/abc.2024.1869.

ABSTRACT

Newborn screening is a major public health concern. In France, it was established in 1972 with systematic screening for phenylketonuria. Subsequently, other screenings, including congenital hypothyroidism, congenital adrenal hyperplasia, cystic fibrosis, and sickle cell disease, were added. The introduction of tandem mass spectrometry in screening laboratories in 2020 enabled the inclusion of eight additional inherited metabolic diseases: aminoacidopathies (tyrosinemia type I, maple syrup urine disease, and homocystinuria), organic acidurias (isovaleric and glutaric type I acidurias), and disorders of fatty acid metabolism (MCADD, long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD), and primary carnitine deficiency). We briefly present these newly added diseases, of which public awareness is still incomplete.

PMID:38638016 | DOI:10.1684/abc.2024.1869

Categories: Literature Watch

Short-term azithromycin use is associated with QTc interval prolongation in children with cystic fibrosis

Thu, 2024-04-18 06:00

Arch Pediatr. 2024 Apr 17:S0929-693X(24)00060-5. doi: 10.1016/j.arcped.2024.02.004. Online ahead of print.

ABSTRACT

BACKGROUND: Azithromycin is used for children with cystic fibrosis (CF) for its immunomodulatory and anti-inflammatory action. This study investigated the short-term alterations in QTc interval associated with azithromycin prophylaxis in pediatric patients with CF.

METHODS: This study included 121 patients with mild CF, of whom 76 received azithromycin (patient group) and 45 did not receive azithromycin (control group). The patient and control groups were categorized according to age as under 12 years of age and over 12 years of age. The first presentation measured all the patient and control groups at basic QTc time intervals. The QTc intervals of all patients were then remeasured systemically at 1, 3, and 6 months. Age categories and QTc intervals that were calculated at each month in the patient and control groups were compared statistically.

RESULTS: A statistically significant difference was detected in the patient group between the initial QTc interval time and the electrocardiogram (ECG) findings in the first and third months after prophylaxis treatment (p < 0.001; p = 0.01). However, no statistically significant difference was detected in the sixth month (p > 0.05) in all groups. Almost all of the children's QTc intervals were within normal range and within the safety zone (under 0.44 s). No statistically significant difference was detected in the control group between the initial ECG and the QTc intervals measured at 1, 3, and 6 months.

CONCLUSION: Short-term use of azithromycin prophylaxis in pediatric patients with mild CF slightly increased the QTc interval in the first and third months of follow-up. Nevertheless, all QTc interval changes fell within the safety zone. Notably, 1 month of follow-up treatment should be performed to check for any alteration in the QTc interval. If increased QTc interval duration is not detected in the first month, azithromycin prophylaxis can be safely prescribed.

PMID:38637249 | DOI:10.1016/j.arcped.2024.02.004

Categories: Literature Watch

Bronchiectasis not due to cystic fibrosis

Thu, 2024-04-18 06:00

Med Clin (Barc). 2024 Apr 17:S0025-7753(24)00145-3. doi: 10.1016/j.medcli.2024.01.023. Online ahead of print.

ABSTRACT

Bronchiectasis is a clinical-radiological condition composed of irreversible bronchial dilation due to inflammation and infection of the airways, which causes respiratory symptoms, usually productive cough and infectious exacerbations. Bronchiectasis can have multiple causes, both pulmonary and extrapulmonary, and its clinical presentation is very heterogenous. Its prevalence is unknown, although up to 35-50% of severe COPD and 25% of severe asthma present them, so their underdiagnosis is evident. Chronic bacterial bronchial infection is common, and Pseudomonas aeruginosa is the pathogen that has been found to imply a worse prognosis. Treatment of bronchiectasis has three fundamental characteristics: it must be multidisciplinary (involvement of several specialties), pyramidal (from primary care to the most specialized units) and multidimensional (management of all aspects that make up the disease).

PMID:38637217 | DOI:10.1016/j.medcli.2024.01.023

Categories: Literature Watch

"Therapeutic improvement of CFTR function and reversibility of bronchiectasis in cystic fibrosis." M.O. Wielputz and M.A. Mall. Eur Respir J 2024; 63: 2400234

Thu, 2024-04-18 06:00

Eur Respir J. 2024 Apr 18;63(4):2450234. doi: 10.1183/13993003.50234-2024. Print 2024 Apr.

NO ABSTRACT

PMID:38636974 | DOI:10.1183/13993003.50234-2024

Categories: Literature Watch

Septin-dependent defense mechanisms against Pseudomonas aeruginosa are stalled in cystic fibrosis bronchial epithelial cells

Thu, 2024-04-18 06:00

Eur J Cell Biol. 2024 Apr 15;103(2):151416. doi: 10.1016/j.ejcb.2024.151416. Online ahead of print.

ABSTRACT

Airway epithelial cells form a physical barrier against inhaled pathogens and coordinate innate immune responses in the lungs. Bronchial cells in people with cystic fibrosis (pwCF) are colonized by Pseudomonas aeruginosa because of the accumulation of mucus in the lower airways and an altered immune response. This leads to chronic inflammation, lung tissue damage, and accelerated decline in lung function. Thus, identifying the molecular factors involved in the host response in the airways is crucial for developing new therapeutic strategies. The septin (SEPT) cytoskeleton is involved in tissue barrier integrity and anti-infective responses. SEPT7 is critical for maintaining SEPT complexes and for sensing pathogenic microbes. In the lungs, SEPT7 may be involved in the epithelial barrier resistance to infection; however, its role in cystic fibrosis (CF) P. aeruginosa infection is unknown. This study aimed to investigate the role of SEPT7 in controlling P. aeruginosa infection in bronchial epithelial cells, particularly in CF. The study findings showed that SEPT7 encages P. aeruginosa in bronchial epithelial cells and its inhibition downregulates the expression of other SEPTs. In addition, P. aeruginosa does not regulate SEPT7 expression. Finally, we found that inhibiting SEPT7 expression in bronchial epithelial cells (BEAS-2B 16HBE14o- and primary cells) resulted in higher levels of internalized P. aeruginosa and decreased IL-6 production during infection, suggesting a crucial role of SEPT7 in the host response against this bacterium. However, these effects were not observed in the CF cells (16HBE14o-/F508del and primary cells) which may explain the persistence of infection in pwCF. The study findings suggest the modification of SEPT7 expression as a potential approach for the anti-infective control of P. aeruginosa, particularly in CF.

PMID:38636185 | DOI:10.1016/j.ejcb.2024.151416

Categories: Literature Watch

Pathophysiology of non-cystic fibrosis bronchiectasis in children and adolescents with asthma: A protocol for systematic review and meta-analysis

Thu, 2024-04-18 06:00

PLoS One. 2024 Apr 18;19(4):e0294921. doi: 10.1371/journal.pone.0294921. eCollection 2024.

ABSTRACT

BACKGROUND: The pathophysiological mechanisms by which asthma and bronchiectasis are associated are still unclear. The association of these two diseases can result in more severe symptoms and a greater number of exacerbations.

OBJECTIVE: The aim of this systematic review is to collect evidence of the pathophysiology of non-cystic fibrosis bronchiectasis with associated asthma in children and adolescents, aged 6-18 years old.

METHODS: A systematic and comprehensive search will be performed using eight main databases, PubMed, PubMed PMC, BVS/BIREME, Scopus, EMBASE, Cochrane Library, Scielo and Web of Science. Articles will be searched from the earliest available time to July 2023. The studied population will be composed of children and adolescents with asthma and non-cystic fibrosis bronchiectasis. From the data obtained, all articles found will be transferred to the Rayyan platform. Study selection will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols Checklist (PRISMA P-2015). In addition, if sufficient data are available, a meta-analysis will be conducted. Two independent reviewers will conduct the studies selection, data extraction, and risk of bias assessment. The outcome measures will be to analyze if non-cystic fibrosis bronchiectasis is related to a specific inflammatory profile.

DISCUSSION: A systematic review will provide better knowledge about the etiopathogenesis and causes of the association between asthma and bronchiectasis and its role in the severity and control of asthma. Identifying, selecting and critically evaluating studies on asthma and bronchiectasis, would be possible to illuminate the characteristics of children and adolescents with associated diagnoses and provide information to help individualized treatments in order to control and prevent complications. The findings of this study will be published in a peer-reviewed journal.

SYSTEMATIC REVIEW REGISTRATION: The systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) in July 2023 (registration number CRD42023440355).

PMID:38635522 | DOI:10.1371/journal.pone.0294921

Categories: Literature Watch

Predictors of Sinonasal Improvement After Highly Effective Modulator Therapy in Adults with Cystic Fibrosis

Thu, 2024-04-18 06:00

Laryngoscope. 2024 Apr 18. doi: 10.1002/lary.31438. Online ahead of print.

ABSTRACT

OBJECTIVES: The 22-question SinoNasal Outcome Test (SNOT-22) assesses chronic rhinosinusitis (CRS) severity. We aimed to identify predictors of SNOT-22 score improvement following highly effective modulator therapy (HEMT) initiation and to corroborate the SNOT-22 minimal clinically important difference (MCID) in adults with cystic fibrosis (CF).

METHODS: Prospective observational data was pooled from four studies across 10 US centers investigating people with CF (PwCF) and CRS. Three studies evaluated HEMT's impact on CRS. For participants enrolled prior to HEMT initiation, SNOT-22 scores were obtained at baseline and after 3-6 months of HEMT. Multivariate regression identified predictors of improvement. Cronbach's alpha and four distribution-based methods were used to assess internal consistency and calculate the MCID of the SNOT-22.

RESULTS: A total of 184 PwCF participated with mean baseline SNOT-22 scores ranging from 18.1 to 56.7. Cronbach's alpha was ≥0.90 across sites. Participants at sites with pre- and post-HEMT data reported improvement in SNOT-22 scores after initiating HEMT (all p < 0.05). Worse baseline SNOT-22 score (odds ratio (OR): 1.05, p < 0.001, 95% CI: 1.02-1.08), F508del homozygosity (OR: 4.30, p = 0.040, 95% CI: 1.14-18.99), and absence of prior modulator therapy (OR: 4.99, p = 0.017, 95% CI: 1.39-20.11) were associated with greater SNOT-22 improvement. The mean MCID calculated via distribution-based methods was 8.5.

CONCLUSION: Worse baseline sinonasal symptoms, F508del homozygosity, and absence of prior modulator therapy predicted greater improvement after HEMT initiation. The mean MCID for SNOT-22 in PwCF is 8.5 points, similar to non-CF individuals with CRS, and provides a threshold specifically for PwCF. The SNOT-22 has strong internal consistency in PwCF.

LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

PMID:38634358 | DOI:10.1002/lary.31438

Categories: Literature Watch

Recommended Tool Compounds for Modifying the Cystic Fibrosis Transmembrane Conductance Regulator Channel Variants

Thu, 2024-04-18 06:00

ACS Pharmacol Transl Sci. 2024 Mar 14;7(4):933-950. doi: 10.1021/acsptsci.3c00362. eCollection 2024 Apr 12.

ABSTRACT

Cystic fibrosis (CF) is a genetic disorder arising from variations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, leading to multiple organ system defects. CFTR tool compounds are molecules that can modify the activity of the CFTR channel. Especially, patients that are currently not able to benefit from approved CFTR modulators, such as patients with rare CFTR variants, benefit from further research in discovering novel tools to modulate CFTR. This Review explores the development and classification of CFTR tool compounds, including CFTR blockers (CFTRinh-172, GlyH-101), potentiators (VRT-532, Genistein), correctors (VRT-325, Corr-4a), and other approved and unapproved modulators, with detailed descriptions and discussions for each compound. The challenges and future directions in targeting rare variants and optimizing drug delivery, and the potential synergistic effects in combination therapies are outlined. CFTR modulation holds promise not only for CF treatment but also for generating CF models that contribute to CF research and potentially treating other diseases such as secretory diarrhea. Therefore, continued research on CFTR tool compounds is critical.

PMID:38633590 | PMC:PMC11019735 | DOI:10.1021/acsptsci.3c00362

Categories: Literature Watch

The role of volatile organic compounds for assessing characteristics and severity of non-cystic fibrosis bronchiectasis: an observational study

Thu, 2024-04-18 06:00

Front Med (Lausanne). 2024 Apr 3;11:1345165. doi: 10.3389/fmed.2024.1345165. eCollection 2024.

ABSTRACT

BACKGROUND: Hypoxic conditions and Pseudomonas aeruginosa (P. aeruginosa) infection are significant factors influencing the prognosis and treatment of patients with bronchiectasis. This study aimed to explore the potential for breath analysis to detect hypoxic conditions and P. aeruginosa infection in bronchiectasis patients by analyzing of volatile organic compounds (VOCs) in exhaled breath condensate (EBC).

METHODS: EBC samples were collected from stable bronchiectasis patients and analyzed using solid phase microextraction-gas chromatography-mass spectrometry (SPME-GCMS). The association of VOCs with bronchiectasis patients' phenotypes including hypoxic conditions and P. aeruginosa isolation was analyzed, which may relate to the severity of bronchiectasis disease.

RESULTS: Levels of 10-heptadecenoic acid, heptadecanoic acid, longifolene, and decanol in the hypoxia group were higher compared to the normoxia group. Additionally, the levels of 13-octadecenoic acid, octadecenoic acid, phenol, pentadecanoic acid, and myristic acid were increased in P. aeruginosa (+) group compared to the P. aeruginosa (-) group. Subgroup analysis based on the bronchiectasis severity index (BSI)reveled that the levels of 10-heptadecenoic acid, heptadecanoic acid, decanol, 13-octadecenoic acid, myristic acid, and pentadecanoic acid were higher in the severe group compared to the moderate group. Multivariate linear regression showed that 10-heptadecenoic acid and age were independent prognostic factors for bronchiectasis patients with hypoxia. Furthermore, octadecenoic acid, phenol and gender were identified as independent prognostic factors for bronchiectasis patients with P. aeruginosa isolation.

CONCLUSION: The study provides evidence that specific VOCs in EBC are correlated with the severity of bronchiectasis, and 10-heptadecenoic acid is shown to be a predictive marker for hypoxia condition in bronchiectasis patients.

PMID:38633315 | PMC:PMC11022847 | DOI:10.3389/fmed.2024.1345165

Categories: Literature Watch

Radiographic Outcomes in Paediatric Bronchiectasis and Factors Associated with Reversibility

Wed, 2024-04-17 06:00

Am J Respir Crit Care Med. 2024 Apr 17. doi: 10.1164/rccm.202402-0411OC. Online ahead of print.

ABSTRACT

RATIONALE: Conventionally considered irreversible, bronchiectasis reversibility in children has been demonstrated in small studies. However, the factors associated with radiographic reversibility in bronchiectasis have yet to be defined.

OBJECTIVES: In a large cohort of children with bronchiectasis, we aimed to determine (a) if and to what extent bronchiectasis is reversible and (b) factors associated with radiographic chest high resolution computed tomography (cHRCT) resolution.

METHODS: We identified children with bronchiectasis who had a repeat multidetector HRCT between 2010-2021. We excluded those with cystic fibrosis, surgical pulmonary resection, traction bronchiectasis only, or lobar opacification.

MAIN RESULTS: cHRCT scans were scored using the modified Reiff-score (MRS) with a paediatric correction. Resolution was defined as absence of abnormal broncho-arterial ratio (>0.8) on the second cHRCT. We included 142 children (median age=5years: IQR 2.6-7.4), Inter- and intra-rater agreement in MRSs was excellent (weighted kappa=0.83-0.86 and 0.95 respectively). Radiographically resolution was documented in 57/142 (40.1%), improved in 56/142 (39.4%), unchanged/worse in 29/142 (20.4%). Pseudomonas aeruginosa (PsA) was absolutely associated with non-resolution. On multivariable regression, in those without PsA cultured, younger age-at-diagnosis (risk ratio (RR)=0.94, 95%CI 0.88-0.99) lower MRS (RR=0.89, 95% CI 0.82-0.97) and lower annual exacerbation rate requiring intravenous antibiotics (RR=0.60, 95%CI 0.37-0.98) increased the likelihood of radiographic resolution.

CONCLUSIONS: This first large cohort confirms bronchiectasis in children is often reversible with appropriate management. Younger aged children and those with lesser radiographic severity at diagnosis were most likely to achieve radiographic reversibility whilst those with PsA infection were least likely.

PMID:38631023 | DOI:10.1164/rccm.202402-0411OC

Categories: Literature Watch

Lipoarabinomannan modification as a source of phenotypic heterogeneity in host-adapted <em>Mycobacterium abscessus</em> isolates

Wed, 2024-04-17 06:00

Proc Natl Acad Sci U S A. 2024 Apr 23;121(17):e2403206121. doi: 10.1073/pnas.2403206121. Epub 2024 Apr 17.

ABSTRACT

Mycobacterium abscessus is increasingly recognized as the causative agent of chronic pulmonary infections in humans. One of the genes found to be under strong evolutionary pressure during adaptation of M. abscessus to the human lung is embC which encodes an arabinosyltransferase required for the biosynthesis of the cell envelope lipoglycan, lipoarabinomannan (LAM). To assess the impact of patient-derived embC mutations on the physiology and virulence of M. abscessus, mutations were introduced in the isogenic background of M. abscessus ATCC 19977 and the resulting strains probed for phenotypic changes in a variety of in vitro and host cell-based assays relevant to infection. We show that patient-derived mutational variations in EmbC result in an unexpectedly large number of changes in the physiology of M. abscessus, and its interactions with innate immune cells. Not only did the mutants produce previously unknown forms of LAM with a truncated arabinan domain and 3-linked oligomannoside chains, they also displayed significantly altered cording, sliding motility, and biofilm-forming capacities. The mutants further differed from wild-type M. abscessus in their ability to replicate and induce inflammatory responses in human monocyte-derived macrophages and epithelial cells. The fact that different embC mutations were associated with distinct physiologic and pathogenic outcomes indicates that structural alterations in LAM caused by nonsynonymous nucleotide polymorphisms in embC may be a rapid, one-step, way for M. abscessus to generate broad-spectrum diversity beneficial to survival within the heterogeneous and constantly evolving environment of the infected human airway.

PMID:38630725 | DOI:10.1073/pnas.2403206121

Categories: Literature Watch

Reply to Kebui R and Emiroglu HH

Wed, 2024-04-17 06:00

J Pediatr Gastroenterol Nutr. 2024 Apr 17. doi: 10.1002/jpn3.12214. Online ahead of print.

NO ABSTRACT

PMID:38629474 | DOI:10.1002/jpn3.12214

Categories: Literature Watch

Cystic fibrosis in Iceland and the high prevalence of the N1303K variant

Wed, 2024-04-17 06:00

Pediatr Pulmonol. 2024 Apr 17. doi: 10.1002/ppul.27019. Online ahead of print.

ABSTRACT

BACKGROUND: Cystic fibrosis (CF) is most common in populations of Northern European ancestry where the F508del variant predominates. In 2020, Iceland became a member of the European Cystic Fibrosis Society Patient Registry, and we launched an epidemiological study of CF in Iceland. The study aimed to determine the prevalence and the genetic variants present in the country. Furthermore, we aimed to describe the previous and the current situation regarding lung function, infections, complications, treatment, and follow-up to understand the strengths and weaknesses of CF care in Iceland.

METHODS: This retrospective study included all individuals in Iceland with a confirmed CF diagnosis between 1955 and 2021. We conducted a medical records search for CF diagnosis codes and found 30 people with CF who were included in the study. Two hundred sixteen clinical variables were registered. A descriptive analysis of these was performed.

RESULTS: The prevalence of CF in Iceland is 0.372:10,000 inhabitants. The F508del is the most common CF transmembrane conductance regulator (CFTR) variant (46.4%), closely followed by N1303K (44.6%). Staphylococcus aureus was the most common airway pathogen, followed by Pseudomonas aeruginosa. Nasal polyps and CF-related diabetes were the most common complications. Modern CF medications, including the recent CFTR modulators, are available.

CONCLUSION: Even though Iceland has a relatively low prevalence of CF, it holds the highest known prevalence of the N1303K variant in Europe. Access to necessary treatment is satisfactory, but improvements are advisable for some aspects of the routine assessments by best practice guidelines.

PMID:38629430 | DOI:10.1002/ppul.27019

Categories: Literature Watch

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

Tue, 2024-04-16 06:00

Adv Drug Deliv Rev. 2024 Apr 14:115305. doi: 10.1016/j.addr.2024.115305. Online ahead of print.

ABSTRACT

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.

PMID:38626860 | DOI:10.1016/j.addr.2024.115305

Categories: Literature Watch

Recessively Inherited Deficiency of Secreted WFDC2 (HE4) Causes Nasal Polyposis and Bronchiectasis

Tue, 2024-04-16 06:00

Am J Respir Crit Care Med. 2024 Apr 16. doi: 10.1164/rccm.202308-1370OC. Online ahead of print.

ABSTRACT

RATIONALE: Bronchiectasis is a pathological dilatation of the bronchi in the respiratory airways associated with environmental or genetic causes (e.g., cystic fibrosis, primary ciliary dyskinesia and primary immunodeficiency disorders), but most cases remain idiopathic.

OBJECTIVES: To identify novel genetic defects in unsolved cases of bronchiectasis presenting with severe rhinosinusitis, nasal polyposis, and pulmonary Pseudomonas aeruginosa infection.

METHODS: DNA was analyzed by next-generation or targeted Sanger sequencing. RNA was analyzed by quantitative PCR and single-cell RNA sequencing. Patient-derived, cells, cell cultures and secretions (mucus, saliva, seminal fluid) were analyzed by Western blotting and immunofluorescence microscopy, and mucociliary activity was measured. Blood serum was analyzed by electrochemiluminescence immunoassay. Protein structure and proteomic analyses were used to assess the impact of a disease-causing founder variant.

MEASUREMENTS AND MAIN RESULTS: We identified bi-allelic pathogenic variants in WFDC2 in 11 individuals from 10 unrelated families originating from the United States, Europe, Asia, and Africa. Expression of WFDC2 was detected predominantly in secretory cells of control airway epithelium and also in submucosal glands. We demonstrate that WFDC2 is below the limit of detection in blood serum and hardly detectable in samples of saliva, seminal fluid, and airway surface liquid from WFDC2-deficient individuals. Computer simulations and deglycosylation assays indicate that the disease-causing founder variant p.Cys49Arg structurally hampers glycosylation and thus secretion of mature WFDC2.

CONCLUSIONS: WFDC2 dysfunction defines a novel molecular etiology of bronchiectasis characterized by the deficiency of a secreted component of the airways. A commercially available blood test combined with genetic testing allows its diagnosis. This article is open access and distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).

PMID:38626355 | DOI:10.1164/rccm.202308-1370OC

Categories: Literature Watch

Molecular analysis of CFTR gene mutations among Iraqi cystic fibrosis patients

Tue, 2024-04-16 06:00

Egypt J Med Hum Genet. 2021;22(1):45. doi: 10.1186/s43042-021-00164-x. Epub 2021 May 11.

ABSTRACT

BACKGROUND: Cystic fibrosis (CF) is an autosomal recessive multisystem disease that results from mutation(s) of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. More than 2100 mutations and polymorphisms have been reported in this gene so far. Incidence and genotyping of CF are under-identified in Iraq. This study aims to determine the types and frequencies of certain CFTR mutations among a sample of Iraqi CF patients. Two groups of patients were included: 31 clinically confirmed CF patients in addition to 47 clinically suspected patients of CF. All confirmed patients had typical, moderate-severe clinical presentation and course of the disease. Molecular analysis was performed on the majority of enrolled patients using the CF-stripAssay® kit supplied by ViennaLab diagnostics, GmbH, Austria.

RESULTS: The mutation-detection rate from the tested 34 mutations in this study was 19.5% and the 8 detected mutations were as follows: 3120+1G>A and W1282X were found in 3 (4.17%) patients each; F508del and R1162X were found in 2 (2.78%) patients each; 3272-26A>G, R347P, I507del, and 2183AA>G were found in 1 (1.38%) patient each. Polymorphic variants of IVS8, namely 5T, 7T, and 9T, were detected in ~ 70%. These results were nearly similar to what was reported in regional countries.

CONCLUSION: Cystic fibrosis seems to be not rare as previously thought. 3120+1G>A and W1282X are the two most commonly detected mutations. F508del needs to be included in all future tests, while the I507del mutation was uniquely reported in this study but not in regional studies.

PMID:38624701 | PMC:PMC8110311 | DOI:10.1186/s43042-021-00164-x

Categories: Literature Watch

Porcine-derived pancreatic enzyme replacement therapy may be linked to chronic hepatitis E virus infection in cystic fibrosis lung transplant recipients

Mon, 2024-04-15 06:00

Gut. 2024 Apr 15:gutjnl-2023-330602. doi: 10.1136/gutjnl-2023-330602. Online ahead of print.

ABSTRACT

OBJECTIVES: In high-income countries hepatitis E virus (HEV) is an uncommonly diagnosed porcine-derived zoonoses. After identifying disproportionate chronic HEV infections in persons with cystic fibrosis (pwCF) postlung transplant, we sought to understand its epidemiology and potential drivers.

DESIGN: All pwCF post-transplant attending our regional CF centre were screened for HEV. HEV prevalence was compared against non-transplanted pwCF and with all persons screened for suspected HEV infection from 2016 to 2022 in Alberta, Canada. Those with chronic HEV infection underwent genomic sequencing and phylogenetic analysis. Owing to their swine derivation, independently sourced pancreatic enzyme replacement therapy (PERT) capsules were screened for HEV.

RESULTS: HEV seropositivity was similar between transplanted and non-transplanted pwCF (6/29 (21%) vs 16/83 (19%); p=0.89). Relative to all other Albertans investigated for HEV as a cause of hepatitis (n=115/1079, 10.7%), pwCF had a twofold higher seropositivity relative risk and this was four times higher than the Canadian average. Only three chronic HEV infection cases were identified in all of Alberta, all in CF lung transplant recipients (n=3/29, 10.3%). Phylogenetics confirmed cases were unrelated porcine-derived HEV genotype 3a. Ninety-one per cent of pwCF were taking PERT (median 8760 capsules/person/year). HEV RNA was detected by RT-qPCR in 44% (47/107) of PERT capsules, and sequences clustered with chronic HEV cases.

CONCLUSION: PwCF had disproportionate rates of HEV seropositivity, regardless of transplant status. Chronic HEV infection was evident only in CF transplant recipients. HEV may represent a significant risk for pwCF, particularly post-transplant. Studies to assess HEV incidence and prevalence in pwCF, and potential role of PERT are required.

PMID:38621922 | DOI:10.1136/gutjnl-2023-330602

Categories: Literature Watch

Parental perceptions of body weight and appetite in infants and toddlers with cystic fibrosis

Mon, 2024-04-15 06:00

Appetite. 2024 Apr 13:107357. doi: 10.1016/j.appet.2024.107357. Online ahead of print.

ABSTRACT

Nutritional status has clinical relevance and is a target of guidance to parents of children with cystic fibrosis (CF). Growth is routinely monitored in CF clinics but there is no standardized way of assessing appetitive behaviors or parents' perceptions of their children's appetite. Greater understanding of these factors could improve clinical guidance regarding parent feeding behaviors. We therefore aimed to assess parent perceptions of child weight, and parent reports of child appetite using the Baby Eating Behavior Questionnaire (BEBQ), in a sample of infants and toddlers with CF, compared with a community sample. We additionally assessed relationships of parent perceptions of child weight with parent feeding behaviors in the sample with CF. Anthropometric and questionnaire data were collected for 32 infants and toddlers with CF, as well as 193 infants and toddlers drawn from RESONANCE, a community cohort study. Parents perceived children with CF to be lower in weight than their actual weight, to a greater extent than was evident in the community sample. Parents who perceived their children with CF to be underweight vs. right weight reported greater slowness in eating on the BEBQ. Parents perceived children with CF to have greater slowness in eating and lower enjoyment of food, compared to parents of children in the community sample, independent of sample differences in child weight, age, and sex. Our results demonstrate the potential utility of the BEBQ in a clinical sample and suggest it may be helpful for clinicians to assess parents' perceptions of their child's weight and appetite to promote a fuller understanding of the child's nutritional status, facilitate appropriate feeding behaviors and alleviate unnecessary concerns.

PMID:38621592 | DOI:10.1016/j.appet.2024.107357

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