Search

In previous studies we developed and introduced a method to examine the transport mechanisms of ions in primary cell cultures of human nasal epithelium. In the current study, substances, especially nicotine, that influence these mechanisms are investigated. Specimens of nasal and paranasal epithelium of patients treated by endonasal surgery because of chronic sinusitis (n=217) were used as primary cell cultures. Cell cultures of smokers (n=83) and non-smokers (n=134) were differentiated. Transepithelial Ussing chamber measurements were performed to examine sodium channel functions and to evaluate the influence of nicotine. These examinations were accompanied by simultaneous continuous capacitance measurements. Whereas transepithelial parameters, such as short-circuit current, (I[sub sc]), potential (V[sub t]) and resistance (R[sub t]), in tissues derived from smokers and non-smokers showed no difference, the transepithelial conductance was reduced immediately in cell cultures with apical application of nicotine (2 mM). This decrease was accompanied by a marked reduction of epithelial surface area. In the presence of nicotine, amiloride (100 μM) completely lost its inhibitory capacity. Amiloride-insensitive sodium channels were unaffected by nicotine, as proved by Na[sup +] substitution. Furthermore, the Na[sup +] channel blocker was accompanied by an increase in intracellular Ca[sup 2+]. We conclude that the nicotine-induced increase in intracellular calcium (Ca[sup 2+]) has stimulated Ca[sup 2+] -dependent protein kinase (PKC). PKC promotes endocytosis removing amiloride-sensitive Na[sup +] channels from the cell membrane into the cell by means of vesicular transport. [ABSTRACT FROM AUTHOR]

Background: We recently demonstrated that elexacaftor/tezacaftor/ivacaftor (ETI) improves the lung clearance index (LCI) and abnormalities in lung morphology detected by magnetic resonance imaging (MRI) in adolescent and adult patients with cystic fibrosis (CF). However, real-world data on the effect of ETI on these sensitive outcomes of lung structure and function in school-age children with CF have not been reported. The aim of this study was therefore to examine the effect of ETI on the LCI and the lung MRI score in children aged 6-11 years with CF and one or two F508del alleles., Methods: This prospective, observational, multicentre, post-approval study assessed the longitudinal LCI up to 12 months and the lung MRI score before and 3 months after initiation of ETI., Results: A total of 107 children with CF including 40 heterozygous for F508del and a minimal function mutation (F/MF) and 67 homozygous for F508del (F/F) were enrolled in this study. Treatment with ETI improved the median (interquartile range (IQR)) LCI in F/MF (-1.0 (-2.0- -0.1); p<0.01) and F/F children (-0.8 (-1.9- -0.2); p<0.001) from 3 months onwards. Further, ETI improved the median (IQR) MRI global score in F/MF (-4.0 (-9.0-0.0); p<0.01) and F/F children (-3.5 (-7.3- -0.8); p<0.001)., Conclusions: ETI improves early abnormalities in lung ventilation and morphology in school-age children with CF and at least one F508del allele in a real-world setting. Our results support early initiation of ETI to reduce or even prevent lung disease progression in school-age children with CF., Competing Interests: Conflicts of interest: M. Stahl, S.Y. Graeber and S. Thee are participants of the Berlin Institute of Health (BIH)-Charité Clinician Scientist Program, and J. Röhmel is participant of the Case Analysis and Decision Support (CADS) program funded by Charité – Universitätsmedizin Berlin and the BIH. M. Stahl reports an Independent Research Innovation Award and honoraria for lectures and participation in advisory boards, all by Vertex Pharmaceuticals Incorporated, outside of the submitted work; she is Chairman of the German CF Research Council (FGM), Treasurer of the German Society of Paediatric Pulmonology (GPP) and was Secretary of the Group CF of the Paediatric Assembly of the ERS. M. Dohna is a participant of the Ellen-Schmidt Habilitationsförderung funded by the Hannover Medical School. S.Y. Graeber reports grants from the German CF Foundation and Vertex Pharmaceuticals Incorporated, and honoraria from Chiesi GmbH and Vertex Pharmaceuticals Incorporated for lectures and participation in advisory boards, outside of the submitted work. O. Sommerburg reports grants and honoraria from Vertex Pharmaceuticals Incorporated for lectures, outside of the submitted work. S.T. Pallenberg is a member of the Else-Kröner Forschungskolleg TITUS. A. Voskrebenzev reports a grant and honoraria for lectures from Siemens Healthineers, outside of the submitted work, holds a patent for a method of quantitative magnetic resonance lung imaging (Voskrebenzev, Gutberlet, Vogel-Claussen; number EP3107066, US-2016-0367200-Al 22.12.2016), and is a stockholder and CEO of BioVisioneers GmbH. K. Schütz reports payments for attending meetings and/or travel from Vertex Pharmaceuticals Incorporated, outside of the submitted work. G. Hansen reports receipt of consultation fees from Sanofi GmbH, outside of the submitted work. F. Doellinger reports payment or honoraria for lectures, presentations, manuscript writing or educational events from Bayer, Bayer Vital, Berlin-Chemie Menarini, Boehringer Ingelheim and Chiesi GmbH, payment for expert testimony from Calyx, and support for attending meetings from Bayer. E. Steinke reports grants from Berlin Institute of Health at Charité Berlin, and payment or honoraria for lectures, presentations, manuscript writing or educational events from Vertex Pharmaceuticals Incorporated. S. Thee reports honoraria for lectures and payment for attending meetings and/or travel from Vertex Pharmaceuticals Incorporated and Viatris, outside of the submitted work. J. Röhmel reports honoraria for lectures from Vertex Pharmaceuticals Incorporated, outside the submitted work; additionally, he is work package leader in BEAT-PCD (ERS-CRC). M.O. Wielpütz reports a grant from Vertex Pharmaceuticals Incorporated, and receipt of consulting fees and honoraria for lectures from Vertex Pharmaceuticals Incorporated and Boehringer Ingelheim, outside of the submitted work. L. Naehrlich reports receipt of fees for a data quality project of the German CF Registry. He is the medical lead of the German CF Registry, the pharmacovigilance study manager of the European Cystic Fibrosis Society Patient Registry and part of the Trial Steering Committee for CF STORM. He also reports grants from the German Center for Lung Research, Vertex Pharmaceuticals and Mukoviszidose Institute, and receipt of medical writing services from Articulate Science. J. Vogel-Claussen reports grants from BMBF, Siemens Healthineers, AstraZeneca, Boehringer Ingelheim and GSK, royalties or licenses from Siemens Healthineers, receipt of consulting fees from AstraZeneca, honoraria for lectures from Siemens Healthineers, AstraZeneca, Boehringer Ingelheim, GSK, Roche, Coreline Soft and Bayer, payments for attending meetings and/or travel from Vertex Pharmaceuticals Incorporated, Bayer, GSK and AstraZeneca, and holds a patent for a method of quantitative magnetic resonance lung imaging (Voskrebenzev, Gutberlet, Vogel-Claussen; number EP3107066, US-2016-0367200-Al 22.12.2016). B. Tümmler reports support for the present study from Bundesministerium für Forschung und Technologie, grants from the German Research Foundation (DFG; CRC 900; Excellence cluster “RESIST”), consultancy fees from Helmholtz Institut für Infektionsforschung, payment or honoraria for lectures, presentations, manuscript writing or educational events from Vertex Pharmaceutical (Germany) Incorporated, participation on a data and safety monitoring board or advisory board with Vertex Pharmaceuticals Incorporated, and leadership roles with Christiane Herzog Stiftung and the Microbiome/Metagenome Group of the German Center for Lung Research (DZL). M.A. Mall reports grants from the German Research Foundation (DFG; SFB-TR 84, and project 450557679) and the German Innovation Fund (01NVF19008), outside of the submitted work. Additionally, he reports receipt of consulting fees from AbbVie, Antabio, Arrowhead, Boehringer Ingelheim, Enterprise Therapeutics, Kither Biotec, Prieris, Recode, Santhera, Splisense and Vertex Pharmaceuticals Incorporated, of honoraria for lectures from Vertex Pharmaceuticals Incorporated and participation in advisory boards from AbbVie, Antabio, Arrowhead, Boehringer Ingelheim, Enterprise Therapeutics, Kither Biotec, Pari and Vertex Pharmaceuticals Incorporated, and of payment for travel from Vertex Pharmaceuticals Incorporated and Boehringer Ingelheim, all outside of the submitted work. He is a Fellow of ERS (FERS). A-M. Dittrich reports support for the present study from the German Center for Lung Research (DZL), Vertex Pharmaceuticals Incorporated and European Cystic Fibrosis Society Clinical Trial Network (ECFS-CTN), grants from Vertex Pharmaceuticals Incorporated, ECFS-CTN, DFG and Christiane Herzog Stiftung, consultancy fees from the c4c consortium, GSK and European Cystic Fibrosis Society. The remaining authors have no potential conflicts of interest to disclose., (Copyright ©The authors 2024.)

Rationale: We recently demonstrated that triple-combination CFTR (cystic fibrosis transmembrane conductance regulator) modulator therapy with elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) improves CFTR function in airway and intestinal epithelia to 40-50% of normal in patients with cystic fibrosis (CF) with one or two F508del alleles. In previous studies, this improvement of CFTR function was shown to improve clinical outcomes; however, effects on the lung clearance index (LCI) determined by multiple-breath washout and abnormalities in lung morphology and perfusion detected by magnetic resonance imaging (MRI) have not been studied. Objectives: To examine the effect of ELX/TEZ/IVA on LCI and lung MRI scores in patients with CF and one or two F508del alleles aged ⩾12 years. Methods: This prospective, observational, multicenter, postapproval study assessed LCI and lung MRI scores before and 8-16 weeks after initiation of ELX/TEZ/IVA. Measurements and Main Results: A total of 91 patients with CF, including 45 heterozygous for F508del and a minimal function mutation (MF) and 46 homozygous for F508del , were enrolled in this study. Treatment with ELX/TEZ/IVA improved LCI in F508del /MF (-2.4; interquartile range [IQR], -3.7 to -1.1; P  < 0.001) and F508del homozygous (-1.4; IQR, -2.4 to -0.4; P  < 0.001) patients. Furthermore, ELX/TEZ/IVA improved the MRI global score in F508del /MF (-6.0; IQR, -11.0 to -1.3; P  < 0.001) and F508del homozygous (-6.5; IQR, -11.0 to -1.3; P  < 0.001) patients. Conclusions: Our data demonstrate that improvement of CFTR function by ELX/TEZ/IVA improves lung ventilation and abnormalities in lung morphology, including airway mucus plugging and wall thickening, in adolescent and adult patients with CF and one or two F508del alleles in a real-world, postapproval setting. Clinical trial registered with www.clinicaltrials.gov (NCT04732910).

Background: Multiple-breath washout (MBW)-derived lung clearance index (LCI) detects early cystic fibrosis (CF) lung disease. LCI was used as an end-point in single- and multicentre settings at highly experienced MBW centres in preschool children. However, multicentre feasibility of MBW in children aged 2-6 years, including centres naïve to this technique, has not been determined systematically., Methods: Following central training, 91 standardised nitrogen MBW investigations were performed in 74 awake preschool children (15 controls, 46 with CF, and 13 with other lung diseases), mean age 4.6±0.9 years at investigation, using a commercially available device across five centres in Germany (three experienced, two naïve to the performance in awake preschool children) with central data analysis. Each MBW investigation consisted of several measurements., Results: Overall success rate of MBW investigations was 82.4% ranging from 70.6% to 94.1% across study sites. The number of measurements per investigation was significantly different between sites ranging from 3.7 to 6.2 (p<0.01), while the mean number of successful measurements per investigation was comparable with 2.1 (range, 1.9 to 2.5; p=0.46). In children with CF, the LCI was increased (median 8.2, range, 6.7-15.5) compared to controls (median 7.3, range 6.5-8.3; p<0.01), and comparable to children with other lung diseases (median 7.9, range, 6.6-13.9; p=0.95)., Conclusion: This study demonstrates that multicentre MBW in awake preschool children is feasible, even in centres previously naïve, with central coordination to assure standardised training, quality control and supervision. Our results support the use of LCI as multicentre end-point in clinical trials in awake preschoolers with CF., Competing Interests: Conflict of interest: M. Stahl reports grants from Mukoviszidose eV, personal fees from Vertex Pharmaceuticals and grants from Christiane Herzog Foundation, during the conduct of the study. Conflict of interest: C. Joachim has nothing to disclose. Conflict of interest: I. Kirsch has nothing to disclose. Conflict of interest: T. Uselmann has nothing to disclose. Conflict of interest: Y. Yu has nothing to disclose. Conflict of interest: N. Alfeis has nothing to disclose. Conflict of interest: C. Berger has nothing to disclose. Conflict of interest: R. Minso has nothing to disclose. Conflict of interest: I. Rudolf has nothing to disclose. Conflict of interest: C. Stolpe has nothing to disclose. Conflict of interest: X. Bovermann has nothing to disclose. Conflict of interest: L. Liboschik has nothing to disclose. Conflict of interest: A. Steinmetz has nothing to disclose. Conflict of interest: D. Tennhardt has nothing to disclose. Conflict of interest: F. Dörfler has nothing to disclose. Conflict of interest: J. Röhmel has nothing to disclose. Conflict of interest: K. Unorji-Frank has nothing to disclose. Conflict of interest: C. Rückes-Nilges has nothing to disclose. Conflict of interest: B. von Stoutz has nothing to disclose. Conflict of interest: L. Naehrlich reports that he has received institutional fees for site participation in clinical trials from Vertex Pharmaceuticals. Conflict of interest: M.V. Kopp has nothing to disclose. Conflict of interest: A-M. Dittrich has nothing to disclose. Conflict of interest: O. Sommerburg has nothing to disclose. Conflict of interest: M.A. Mall reports grants from the German Federal Ministry of Education and Research and the Einstein Foundation Berlin during the conduct of the study; advisory board, consultancy, lecture and clinical trial fees from Boehringer Ingelheim, advisory board and consultancy fees from Arrowhead Pharmaceuticals, advisory board, consultancy, lecture and clinical trial fees from Vertex Pharmaceuticals, advisory board and consultancy fees from Santhera, consultancy fees from Galapagos and Sterna Biologicals, advisory board and consultancy fees from Enterprise Therapeutics, and consultancy fees from Antabio, outside the submitted work., (Copyright ©ERS 2020.)

Chronic airway inflammation in children with asthma might be present even in the absence of pathological lung function tests and is known to increase the risk of permanent pulmonary damage. Thus, we aimed at investigating to what extent inflammatory markers such as leukotrienes (LTs) in exhaled breath condensate (EBC) or fractional exhaled nitric oxide (FE(NO)) reflect therapeutic effects in these patients. Fifty steroid-naive patients (aged 8.8 +/- 2.7 years) were included in the study. EBC was collected before and 6 months after therapy with inhaled corticosteroids. LTs were determined by using commercially available ELISA. In addition, FE(NO) was measured by means of a chemiluminescence analyzer. Conventional lung function testing was performed revealing vital capacity, forced expiratory volume, maximum expiratory flow, and specific resistance. In EBC, LTE(4) but not LTB(4) levels significantly decreased after steroid therapy from 45.3 +/- 36.0 pg/mL to 17.2 +/- 11.4 pg/mL (p < 0.0001) concomitant with a slight, but significant improvement of lung function parameters. Mean FE(NO) also indicated therapeutic success; however, in 20 of 50 patients, exhaled NO concentrations were higher after therapy. These findings suggest that LTE(4) in breath condensate may be helpful in latent inflammatory activity in the bronchial mucosa in children with asthma.

Nitric oxide (NO) has been reported to activate Cl- secretion via the cystic fibrosis transmembrane conductance regulator (CFTR) and inhibit epithelial Na+ absorption mediated by amiloride-sensitive epithelial Na+ channels (ENaC). These ion transport systems are defective in cystic fibrosis (CF): Cl- secretion by CFTR is impaired and Na+ absorption by ENaC is dramatically increased. By activating CFTR and depressing ENaC, NO is a potentially beneficial therapeutic agent for ion transport defects in human CF respiratory epithelia. To assess the effects of NO on human respiratory epithelial cells, the NO donors sodium nitroprusside (SNP) and spermine NONOate were applied to primary cultured nasal cells, surgically obtained from non-CF and CF patients. Measurements of transepithelial short-circuit current (ISC) showed that NO has no inhibitory potency against amiloride-sensitive nasal ENaC (nENaC) or amiloride-insensitive Na+-absorbing mechanisms in non-CF and CF epithelia. Furthermore, NO had no stimulatory effect on Cl- secretion by CFTR or any other Cl- conductance pathway in either tissue. Although NO elevated the intracellular Ca2+ concentration, we did not detect any activation of Ca2+-dependent Cl- channels. These results demonstrate that NO has no beneficial effect on CF epithelial cells of the upper airways.

Na+ and Cl- currents were studied in primary cultures of human nasal epithelium derived from non-cystic fibrosis (non-CF) and cystic fibrosis (CF) patients. We found that Na+ absorption dominates transepithelial transport and the Na+ current contains an amiloride-sensitive and amiloride-insensitive component. In non-CF tissue both components contribute about equally to the entire short-circuit current (ISC), whereas in CF tissues the major part of the current is amiloride-sensitive. Na+ removal reduced ISC to values close to zero. Several Cl- channel blockers were used to identify the remaining tiny Na+-independent current. Under unstimulated, physiological conditions in the presence of Cl- on both sides and amiloride on the apical side of the epithelium diphenylamine-2-carboxic acid (DPC), 4,4'-diisothiocyanatostilbene-2, 2'- disulfonic acid (DIDS) and 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) failed to induce clearcut inhibition of ISC. cAMP as well as ATP did not affect ISC either in CF or in non-CF epithelia. Reduction of apical Cl- increased ISC and depolarized transepithelial potential; however, the observed increase was insensitive to DIDS, DPC and NPPB. From these data we conclude that Cl- conductances in primary cultures of human nasal epithelium derived from CF patients as well as from non-CF patients are present only in low numbers or do not contribute significantly to transepithelial ion transport.