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"Janssens, Hettie M."
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A functional CFTR assay using primary cystic fibrosis intestinal organoids
by
Bronsveld, Inez
,
Brandsma, Arianne M
,
Clevers, Hans
in
1678/631/45/269
,
1877/631/532/2437
,
347/631/1647/1407/652
2013
Building on earlier work, Dekkers
et al
. describe the first application of their intestinal organoid culture technology to the study of human disease, in this case cystic fibrosis. These so called 'mini-guts', which recapitulate the essential
in vivo
intestinal tissue architecture
in vitro
, are used to develop a rapid and quantitative assay to measure mutant cystic fibrosis transmembrane conductance regulator (CFTR) function, as well as test the efficacy of correctors and potentiators of mutant CFTR.
We recently established conditions allowing for long-term expansion of epithelial organoids from intestine, recapitulating essential features of the
in vivo
tissue architecture. Here we apply this technology to study primary intestinal organoids of people suffering from cystic fibrosis, a disease caused by mutations in
CFTR
, encoding cystic fibrosis transmembrane conductance regulator. Forskolin induces rapid swelling of organoids derived from healthy controls or wild-type mice, but this effect is strongly reduced in organoids of subjects with cystic fibrosis or in mice carrying the Cftr F508del mutation and is absent in
Cftr
-deficient organoids. This pattern is phenocopied by CFTR-specific inhibitors. Forskolin-induced swelling of
in vitro
–expanded human control and cystic fibrosis organoids corresponds quantitatively with forskolin-induced anion currents in freshly excised
ex vivo
rectal biopsies. Function of the CFTR F508del mutant protein is restored by incubation at low temperature, as well as by CFTR-restoring compounds. This relatively simple and robust assay will facilitate diagnosis, functional studies, drug development and personalized medicine approaches in cystic fibrosis.
Journal Article
Patient-Specific Modeling of Regional Antibiotic Concentration Levels in Airways of Patients with Cystic Fibrosis: Are We Dosing High Enough?
by
van Holsbeke, Cedric
,
Janssens, Hettie M.
,
Tiddens, Harm A. W. M.
in
Abnormalities
,
Administration, Inhalation
,
Adolescent
2015
Pseudomonas aeruginosa (Pa) infection is an important contributor to the progression of cystic fibrosis (CF) lung disease. The cornerstone treatment for Pa infection is the use of inhaled antibiotics. However, there is substantial lung disease heterogeneity within and between patients that likely impacts deposition patterns of inhaled antibiotics. Therefore, this may result in airways below the minimal inhibitory concentration of the inhaled agent. Very little is known about antibiotic concentrations in small airways, in particular the effect of structural lung abnormalities. We therefore aimed to develop a patient-specific airway model to predict concentrations of inhaled antibiotics and to study the impact of structural lung changes and breathing profile on local concentrations in airways of patients with CF.
In- and expiratory CT-scans of children with CF (5-17 years) were scored (CF-CT score), segmented and reconstructed into 3D airway models. Computational fluid dynamic (CFD) simulations were performed on 40 airway models to predict local Aztreonam lysine for inhalation (AZLI) concentrations. Patient-specific lobar flow distribution and nebulization of 75 mg AZLI through a digital Pari eFlow model with mass median aerodynamic diameter range were used at the inlet of the airway model. AZLI concentrations for central and small airways were computed for different breathing patterns and airway surface liquid thicknesses.
In most simulated conditions, concentrations in both central and small airways were well above the minimal inhibitory concentration. However, small airways in more diseased lobes were likely to receive suboptimal AZLI. Structural lung disease and increased tidal volumes, respiratory rates and larger particle sizes greatly reduced small airway concentrations.
CFD modeling showed that concentrations of inhaled antibiotic delivered to the small airways are highly patient specific and vary throughout the bronchial tree. These results suggest that anti-Pa treatment of especially the small airways can be improved.
Journal Article
Protecting clinical trials in cystic fibrosis during the SARS-CoV-2 pandemic: risks and mitigation measures
by
Dufeu, Nadine
,
Hayes, Kate
,
Janssens, Hettie M.
in
Biomedicine
,
Care and treatment
,
Clinical trials
2021
The SARS-CoV-2 pandemic has disrupted clinical trials worldwide. The European Cystic Fibrosis Society-Clinical Trials Network (ECFS-CTN) has tracked clinical trial disruption by surveying its 58 trial sites across 17 European countries and collated information on measures to mitigate the impact of the pandemic and ensure trial continuity. Here, we present recommendations on how to reduce the risk of SARS-CoV-2 exposure to patients and trial staff by implementing remote trial visits where possible, using home assessments, video and phone calls, electronic consent, and home delivery of study drugs. We discuss the practicalities of remote source data verification, protocol amendments, changing trial site location, and staff absences and home working. We outline recommendations on how to protect trial outcomes, including home assessments, safety reporting, protocol deviations, and recruitment challenges. Finally, we discuss the importance of continued access to study drugs via extension trials for some patients. This guidance was co-created from the shared knowledge and experience of sites in our network and was re-distributed directly to all ECFS-CTN sites to help mitigate the impact of further waves of the SARS-CoV-2 pandemic. We will also use this guidance to assist companies, academia, and consortia with future protocol design and risk mitigation plans. This guidance can be applied to clinical trials in other diseases and could help sites that are not supported by clinical trial networks.
Journal Article
Exploratory Study of Signals for Asthma Drugs in Children, Using the EudraVigilance Database of Spontaneous Reports
by
Sturkenboom, Miriam C. J. M.
,
Janssens, Hettie M.
,
Baan, Esmé J.
in
Asthma
,
Budesonide
,
Children
2020
Introduction
As asthma medications are frequently prescribed for children, knowledge of the safety of these drugs in the paediatric population is important. Although spontaneous reports cannot be used to prove causality of adverse events, they are important in the detection of safety signals.
Objective
Our objective was to provide an overview of adverse drug events associated with asthma medications in children from a spontaneous reports database and to identify new signals.
Methods
Spontaneous reports concerning asthma drugs were obtained from EudraVigilance, the European Medicine Agency’s database for suspected adverse drug reactions. For each drug–event combination, we calculated the proportional reporting ratio (PRR) in the study period 2011–2017. Signals in children (aged 0–17 years) were compared with signals in the whole population. Analyses were repeated for different age categories, by sex and by therapeutic area.
Results
In total, 372,345 reports in children resulted in 385 different signals concerning asthma therapy. The largest group consisted of psychiatric events (65 signals). Only 30 signals were new, with seven, including herpes viral infections, associated with omalizumab. Stratification by age, sex and therapeutic area provided additional new signals, such as hypertrichoses with budesonide and encephalopathies with theophylline. Of all signals in children, 60 (16%) did not appear in the whole population.
Conclusions
The majority of signals regarding asthma therapy in children were already known, but we also identified new signals. We showed that signals can be masked if age stratification is not conducted. Further exploration is needed to investigate the risk and causality of the newly found signals.
Journal Article
Characterization of the SPIRITAS: A Disposable Sampling Setup for Volatile Organic Compound Collection and Analysis
by
Vijverberg, Susanne J. H.
,
Terheggen-Lagro, Suzanne W. J.
,
Janssens, Hettie M.
in
Biomarkers
,
Breath tests
,
Carbon
2024
Analyzing exhaled breath for volatile organic compounds (VOCs) using thermal desorption–gas chromatography–mass spectrometry (TD-GC-MS) offers a non-invasive diagnostic approach for various diseases. Despite its promise, the method faces challenges like sampling heterogeneity and high costs. Following the European Respiratory Society’s advocacy for methodological standardization, we developed the SPIRITAS (Standardized Product for Inexpensive Respiratory InvesTigation: A breath Sampler), a low-cost, disposable breath sampler. This study evaluates the SPIRITAS’s effectiveness in detecting targeted VOCs. We tested the SPIRITAS using the Peppermint Experiment, a standardized protocol that allows for comparison between different breath sampling and analytical practices by assessing the ability to detect five peppermint-specific VOCs after ingestion of a 200-milligram peppermint oil capsule. We included ten subjects and performed six breath samples per participant, including a baseline measurement taken before ingestion. We used the Wilcoxon signed-rank test to evaluate whether baseline values were significantly lower than the peak values of the targeted VOCs. Additionally, we conducted an experiment utilizing humidified medical-grade air to identify any VOCs attributable to the SPIRITAS setup itself. Results showed successful detection of four out of five targeted “peppermint-associated” VOCs: alpha-pinene (p ≤ 0.01), beta-pinene (p ≤ 0.01), menthone (p = 0.01), and menthol (p = 0.02), indicating significant differences between the baseline and peak values in the volunteers’ breath. However, detection of eucalyptol was inconsistent. In addition, we identified 16 VOCs that were released by the SPIRITAS, one of which remains unidentified. Our findings underscore the SPIRITAS’s potential for clinical applications, paving the way for broader biomarker research. The combination of ease of use, low cost, reduced risk of contamination, and standardization makes SPIRITAS very suitable for large-scale international studies. Furthermore, we have demonstrated the SPIRITAS’s effectiveness in detecting specific VOCs and identified 16 compounds originating from the SPIRITAS, ensuring that these compounds would not be mis-qualified as potential biomarkers in future clinical studies.
Journal Article
The Omega‐6 Lipid pathway shift is associated with neutrophil influx and structural lung damage in early cystic fibrosis lung disease
by
Slimmen, Lisa JM
,
Broos, Jelle Y
,
Kooij, Gijs
in
alveolar macrophages
,
Arachidonic acid
,
Bronchus
2024
Objectives
In cystic fibrosis (CF), an imbalanced lipid metabolism is associated with lung inflammation. Little is known about the role that specific lipid mediators (LMs) exert in CF lung inflammation, and whether their levels change during early disease progression. Therefore, we measured airway LM profiles of young CF patients, correlating these with disease‐associated parameters.
Methods
Levels of omega (ω)‐3/6 PUFAs and their LM derivatives were determined in bronchoalveolar lavage fluid (BALF) of children with CF ages 1–5 using a targeted high‐performance liquid chromatography–tandem mass spectrometry approach. Hierarchical clustering analysis was performed on relative LM levels. Individual relative LM levels were correlated with neutrophilic inflammation (BALF %Neu) and structural lung damage (PRAGMA‐CF %Disease). Significant correlations were included in a backward multivariate linear regression model to identify the LMs that are best related to disease progression.
Results
A total of 65 BALF samples were analysed for ω‐3/6 lipid content. LM profiles clustered into an arachidonic acid (AA)‐enriched and a linoleic acid (LA)‐enriched sample cluster. AA derivatives like 17‐OH‐DH‐HETE, 5‐HETE, 5,15‐diHETE, 15‐HETE, 15‐KETE, LTB4 and 6‐trans‐LTB4 positively correlated with BALF %Neu and/or PRAGMA %Dis. Contrastingly, 9‐HoTrE and the LA derivatives 9‐HoDE, 9(10)‐EpOME, 9(10)‐DiHOME, 13‐HoDE, 13‐oxoODE and 12(13)‐EpOME negatively correlated with BALF %Neu and/or PRAGMA %Dis. 6‐trans‐LTB4 was the strongest predictor for BALF %Neu. 5‐HETE and 15‐KETE contributed most to PRAGMA %Dis prediction.
Conclusions
Our data provide more insight into the lung lipidome of infants with CF, and show that a shift from LA derivatives to AA derivatives in BALF associates with early CF lung disease progression.
In early cystic fibrosis lung disease, a switch in the ω‐6 lipid pathway towards arachidonic acid derivatives associates with increased neutrophilic influx and structural lung damage, highlighting the need for timely intervention that mitigates lung inflammation.
Journal Article
Antigen-Presenting Cells in the Airways: Moderating Asymptomatic Bacterial Carriage
by
Slimmen, Lisa J. M.
,
Unger, Wendy W. J.
,
Janssens, Hettie M.
in
Antigen-presenting cells
,
Antigens
,
Asymptomatic
2021
Bacterial respiratory tract infections (RTIs) are a major global health burden, and the role of antigen-presenting cells (APCs) in mounting an immune response to contain and clear invading pathogens is well-described. However, most encounters between a host and a bacterial pathogen do not result in symptomatic infection, but in asymptomatic carriage instead. The fact that a pathogen will cause infection in one individual, but not in another does not appear to be directly related to bacterial density, but rather depend on qualitative differences in the host response. Understanding the interactions between respiratory pathogens and airway APCs that result in asymptomatic carriage, will provide better insight into the factors that can skew this interaction towards infection. This review will discuss the currently available knowledge on airway APCs in the context of asymptomatic bacterial carriage along the entire respiratory tract. Furthermore, in order to interpret past and futures studies into this topic, we propose a standardized nomenclature of the different stages of carriage and infection, based on the pathogen’s position with regard to the epithelium and the amount of inflammation present.
Journal Article
Elastase Exocytosis by Airway Neutrophils Is Associated with Early Lung Damage in Children with Cystic Fibrosis
by
Margaroli, Camilla
,
Mall, Marcus A.
,
Kicic, Anthony
in
Biomarkers
,
Child, Preschool
,
Cystic fibrosis
2019
Neutrophils are recruited to the airways of individuals with cystic fibrosis (CF). In adolescents and adults with CF, airway neutrophils actively exocytose the primary granule protease elastase (NE), whose extracellular activity correlates with lung damage. During childhood, free extracellular NE activity is measurable only in a subset of patients, and the exocytic function of airway neutrophils is unknown.
To measure NE exocytosis by airway neutrophils in relation to free extracellular NE activity and lung damage in children with CF.
We measured lung damage using chest computed tomography coupled with the Perth-Rotterdam Annotated Grid Morphometric Analysis for Cystic Fibrosis scoring system. Concomitantly, we phenotyped blood and BAL fluid leukocytes by flow and image cytometry, and measured free extracellular NE activity using spectrophotometric and Förster resonance energy transfer assays. Children with airway inflammation linked to aerodigestive disorder were enrolled as control subjects.
Children with CF but not disease control children harbored BAL fluid neutrophils with high exocytosis of primary granules, before the detection of bronchiectasis. This measure of NE exocytosis correlated with lung damage (R = 0.55; P = 0.0008), whereas the molecular measure of free extracellular NE activity did not. This discrepancy may be caused by the inhibition of extracellular NE by BAL fluid antiproteases and its binding to leukocytes.
NE exocytosis by airway neutrophils occurs in all children with CF, and its cellular measure correlates with early lung damage. These findings implicate live airway neutrophils in early CF pathogenesis, which should instruct biomarker development and antiinflammatory therapy in children with CF.
Journal Article
Development of the Nasopharyngeal Microbiota in Infants with Cystic Fibrosis
by
de Winter-de Groot, Karin M.
,
de Steenhuijsen Piters, Wouter A. A.
,
van der Ent, Cornelis K.
in
Anti-Bacterial Agents - therapeutic use
,
Burkholderia - genetics
,
Burkholderia Infections - drug therapy
2016
Cystic fibrosis (CF) is characterized by early structural lung disease caused by pulmonary infections. The nasopharynx of infants is a major ecological reservoir of potential respiratory pathogens.
To investigate the development of nasopharyngeal microbiota profiles in infants with CF compared with those of healthy control subjects during the first 6 months of life.
We conducted a prospective cohort study, from the time of diagnosis onward, in which we collected questionnaires and 324 nasopharynx samples from 20 infants with CF and 45 age-matched healthy control subjects. Microbiota profiles were characterized by 16S ribosomal RNA-based sequencing.
We observed significant differences in microbial community composition (P < 0.0002 by permutational multivariate analysis of variance) and development between groups. In infants with CF, early Staphylococcus aureus and, to a lesser extent, Corynebacterium spp. and Moraxella spp. dominance were followed by a switch to Streptococcus mitis predominance after 3 months of age. In control subjects, Moraxella spp. enrichment occurred throughout the first 6 months of life. In a multivariate analysis, S. aureus, S. mitis, Corynebacterium accolens, and bacilli were significantly more abundant in infants with CF, whereas Moraxella spp., Corynebacterium pseudodiphtericum and Corynebacterium propinquum and Haemophilus influenzae were significantly more abundant in control subjects, after correction for age, antibiotic use, and respiratory symptoms. Antibiotic use was independently associated with increased colonization of gram-negative bacteria such as Burkholderia spp. and members of the Enterobacteriaceae bacteria family and reduced colonization of potential beneficial commensals.
From diagnosis onward, we observed distinct patterns of nasopharyngeal microbiota development in infants with CF under 6 months of age compared with control subjects and a marked effect of antibiotic therapy leading toward a gram-negative microbial composition.
Journal Article
CFTR Function Restoration upon Elexacaftor/Tezacaftor/Ivacaftor Treatment in Patient-Derived Intestinal Organoids with Rare CFTR Genotypes
by
Muilwijk, Danya
,
van der Ent, Cornelis K.
,
Bierlaagh, Marlou C.
in
Benzodioxoles - pharmacology
,
Benzodioxoles - therapeutic use
,
Cystic fibrosis
2023
Cystic fibrosis (CF) is caused by mutations in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene. The combination of the CFTR modulators elexacaftor, tezacaftor, and ivacaftor (ETI) enables the effective rescue of CFTR function in people with the most prevalent F508del mutation. However, the functional restoration of rare CFTR variants remains unclear. Here, we use patient-derived intestinal organoids (PDIOs) to identify rare CFTR variants and potentially individuals with CF that might benefit from ETI. First, steady-state lumen area (SLA) measurements were taken to assess CFTR function and compare it to the level observed in healthy controls. Secondly, the forskolin-induced swelling (FIS) assay was performed to measure CFTR rescue within a lower function range, and to further compare it to ETI-mediated CFTR rescue in CFTR genotypes that have received market approval. ETI responses in 30 PDIOs harboring the F508del mutation served as reference for ETI responses of 22 PDIOs with genotypes that are not currently eligible for CFTR modulator treatment, following European Medicine Agency (EMA) and/or U.S. Food and Drug Administration (FDA) regulations. Our data expand previous datasets showing a correlation between in vitro CFTR rescue in organoids and corresponding in vivo ppFEV1 improvement upon a CFTR modulator treatment in published clinical trials, and suggests that the majority of individuals with rare CFTR variants could benefit from ETI. CFTR restoration was further confirmed on protein levels using Western blot. Our data support that CFTR function measurements in PDIOs with rare CFTR genotypes can help to select potential responders to ETI, and suggest that regulatory authorities need to consider providing access to treatment based on the principle of equality for people with CF who do not have access to treatment.
Journal Article