Frequency of cytokine gene promoter polymorphisms in the Northern Ireland Cystic Fibrosis population

It has been postulated that cytokine allele frequencies are gender and perhaps geographically-specific. Cytokine release is crucial in the regulation of the type and magnitude of the immune response. This study observed no differences in the frequency of cytokine promoter polymorphisms associated with variant levels of expression in patients with CIF and a non-CF population of Northern Ireland. (c) 2007 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Molecular characterization and phylogenetic analysis of quinolone resistance-determining regions (QRDRs) of gyrA, gyrB, parC and parE gene loci in viridans group streptococci isolated from adult patients with cystic fibrosis

This study demonstrated key resistance genes to fluroquinilones in Streptococcci isolated from sputum of people with CF. This suggests that other bacteria which are sometimes considered commensal may be a resovoir for resistance. Jse designed the study with Moore.

Cystic fibrosis research in allied health and nursing professions

This report is the result of the "Allied Health and Nursing Professions Working Group" meeting which took place in Verona, Italy, November 2009, which was organised by the European Cystic Fibrosis Society, and involved 32 experts. The meeting was designed to provide a "roadmap" of high priority research questions that can be addressed by Allied Health Professionals (AHP) and nursing. The other goal was to identify research skills that would be beneficial to AHP and nursing researchers and would ultimately improve the research capacity and capability of these professions. The following tasks were accomplished: 1) a Delphi survey was used to identify high priority research areas and themes, 2) common research designs used in AHP and nursing research were evaluated in terms of their strengths and weaknesses, 3) methods for assessing the clinimetric and psychometric properties, as well as feasibility, of relevant outcome measures were reviewed, and 4) a common skill set for AHPs and nurses undertaking clinical research was agreed on and will guide the planning of future research opportunities. This report has identified important areas and themes for future research which include: adherence; physical activity/exercise; nutritional interventions; interventions for the newborn with CF and evaluation of outcome measures for use in AHP and nursing research. It has highlighted the significant challenges AHPs and nurses experience in conducting clinical research, and proposes strategies to overcome these challenges. It is hoped that this report will encourage research initiatives that assess the efficacy/effectiveness of AHP and nursing interventions in order to improve the evidence base. This should increase the quality of research conducted by these professions, justify services they currently provide, and expand their skills in new areas, with the ultimate goal of improving care for patients with CF.

EXPRESSION OF THE INFLAMMATORY REGULATOR A20 CORRELATES WITH LUNG FUNCTION IN PATIENTS WITH CYSTIC FIBROSIS

Abstract: Background: A20 and TAX1BP1 interact to negatively regulate NF-
-driven inflammation. A20 expression is altered in F508del/F508del
patients. Here we explore the effect of CFTR and CFTR genotype on A20 and
TAX1BP1expression. The relationship with lung function is also assessed.
Methods: Primary Nasal Epithelial cells (NECs) from CF patients
(F508del/F508del, n=8, R117H/F508del, n=6) and Controls (age-matched,
n=8), and 16HBE14o- cells were investigated. A20 and TAX1BP1 gene
expression was determined by qPCR.
Results: Silencing of CFTR reduced basal A20 expression. Following LPS
stimulation A20 and TAX1BP1 expression was induced in control NECs and
reduced in CF NECs, broadly reflecting the CF genotype: F508del/F508del
had lower expression than R117H/F508del. A20, but not TAX1BP1 expression,
was proportional to FEV1 in all CF patients (r=0.968, p<0.001).
Conclusions: A20 expression is reduced in CF and is proportional to FEV1.
Pending confirmation in a larger study, A20 may prove a novel predictor
of CF inflammation/disease severity.

Multicentre trial of weekly risedronate on bone density in adults with cystic fibrosis

Background: The aim of this study was to assess the efficacy, tolerability and safety of risedronate in adults with CF. Methods: Patients with a lumbar spine (LS), total hip (TH) or femoral neck (FN) bone mineral density (BMD) Z-score of -1 or less were randomised to receive risedronate 35mg weekly or placebo, and calcium (1g)+vitamin D (800IU). Results: At baseline, BMD Z-scores in the risedronate (n = 17) and placebo (n = 19) groups were similar. By 24. months, 7/17 risedronate patients vs 0/19 placebo patients stopped the study medication due to bone pain. After 24. months treatment, the mean difference (95% CI) in change in LS, TH and FN BMD between the risedronate vs placebo groups was 4.3% (0.4, 8.2) p = 0.03; 4.0% (-0.5, 8.6) p = 0.08; and 2.4% (-3.5, 8.2) p =0.41. Conclusions: After two years treatment there was a significant increase in LS BMD with weekly risedronate compared to placebo. © 2011 European Cystic Fibrosis Society.

Lung clearance index: Evidence for use in clinical trials in cystic fibrosis

The ECFS-CTN Standardisation Committee has undertaken this review of lung clearance index as part of the group's work on evaluation of clinical endpoints with regard to their use in multicentre clinical trials in CF. The aims were 1) to review the literature on reliability, validity and responsiveness of LCI in patients with CF, 2) to gain consensus of the group on feasibility of LCI and 3) to gain consensus on answers to key questions regarding the promotion of LCI to surrogate endpoint status. It was concluded that LCI has an attractive feasibility and clinimetric properties profile and is particularly indicated for multicentre trials in young children with CF and patients with early or mild CF lung disease. This is the first article to collate the literature in this manner and support the use of LCI in clinical trials in CF.

Burkholderia cepacia complex epidemiology in persons with cystic fibrosis from Australia and New Zealand

The Burkholderia cepacia complex (Bcc) is a group of significant opportunistic respiratory pathogens which affect people with cystic fibrosis. In this study, we sought to ascertain the epidemiology and geographic species distribution of 116 Bcc isolates collected from people with CF in Australia and New Zealand. We performed a combination of recA-based PCR, amplified rDNA restriction analysis (ARDRA), pulsed-field gel electrophoresis and repetitive extragenic palindromic PCR on each isolate. Each Burkholderia cenocepacia isolate was also screened by PCR for the presence of the B. cepacia epidemic strain marker. One hundred and fourteen isolates were assigned to a species using recA-based PCR and ARDRA. B. cenocepacia, B. multivorans and B. cepacia accounted for 45.7%, 29.3% and 11.2% of the isolates, respectively. Strain analysis of B. cenocepacia revealed that 85.3% of the isolates were unrelated. One related B. cenocepacia strain was identified amongst 15 people. Whilst full details of person-to-person contact was not available, all patients attended CF centres in Queensland (Qld) and New South Wales (NSW). Although person-to-person transmission of B. cenocepacia strains has occurred in Australia, the majority of CF-related Bcc infections in Australia and New Zealand are most likely acquired from the environment.

Targeting Trypsin-Like Proteases: A Mechanism to Restore Mucociliary Function in Cystic Fibrosis Airways

Dehydration of the airway surface liquid (ASL) and the resultant decline in function of the mucociliary escalator in cystic fibrosis airways is largely underpinned by the excessive flux of Na+ and water though ENaC. Proteolysis of the endogenous  and  subunits of epithelial sodium channels (ENaC) by channel activating proteases (CAPS) is the key regulatory mechanism for channel activation. Recent reports highlight that (1) CFTR (cystic fibrosis transmembrane conductance regulator) normally protects ENaC from the action of proteases and (2) a stark imbalance in proteases/protease inhibitor levels in CF airway cultures favour activation of normally inactive ENaC. The current study examines the potential therapeutic benefit of CAPS/ENaC inhibition in CF airways.
Our group has developed a panel of active-site directed affinity-based probes which target and inhibit trypsin-like proteases (potential CAPS); including the broad-spectrum inhibitor QUB-TL1. We have utilised this compound to interrogate the impact of trypsin-like protease inhibition on ENaC activity in differentiated primary airway epithelial cell cultures.
Electrophysiological data demonstrate QUB-TL1 selectively and irreversibly binds to extracellularly located trypsin-like proteases resulting in impaired ENaC-mediated Na+ transport. Visualisation of ENaC at the apical surface compartment of primary airway epithelial cells shows a large reduction in a low molecular weight (processed and active) form of ENaC, which was found to be abundant in untreated CF cultures. Consistent with the reduction in ENaC activity observed, QUB-TL1 treatment was subsequently shown to increase ASL height (performed in collaboration with Royal College of Surgeons in Ireland).
Our results are consistent with the hypothesis that targeting the CAPS-ENaC signalling axis may restore the depleted ASL seen in CF airways.

Short-chain fatty acids cause an IL-8 response in cystic fibrosis airways via increased GPR41

RATIONALE: Anaerobic bacteria are present in large numbers in the airways of people with cystic fibrosis (PWCF). In the gut, anaerobes produce short-chain fatty acids (SCFAs) that modulate immune/inflammatory processes.

OBJECTIVES: To investigate the capacity of anaerobes to contribute to CF airway pathogenesis via SCFAs.

METHODS: Samples from 109 PWCF were processed using anaerobic microbiological culture with bacteria present identified by 16S RNA sequencing. SCFAs levels in anaerobe supernatants and bronchoalveolar lavage (BAL) were determined by gas chromatography. The mRNA and/or protein expression of SCFAs receptors, GPR41 and GPR43, in CF and non-CF bronchial brushings, and 16HBE14o- and CFBE41o- cells were evaluated using RT-PCR, western blot, laser scanning cytometry and confocal microscopy. SCFAs-induced IL-8 secretion was monitored by ELISA.

MEASUREMENTS AND MAIN RESULTS: Fifty seven of 109 (52.3%) PWCF were anaerobe-positive. Prevalence increased with age, from 33.3% to 57.7% in PWCF under (n=24) and over 6 years (n=85). All evaluated anaerobes produced millimolar concentrations of SCFAs, including acetic, propionic and butyric acid. SCFAs levels were higher in BAL samples from adults than children. GPR41 levels were elevated in; CFBE41o- versus 16HBE14o- cells; CF versus non-CF bronchial brushings; 16HBE14o- cells after treatment with CFTR inhibitor CFTR(inh)-172, CF BAL, or inducers of endoplasmic reticulum stress. SCFAs induced a dose-dependent and pertussis toxin-sensitive IL-8 response in bronchial epithelial cells with a higher production of IL-8 in CFBE41o- than 16HBE14o- cells.

CONCLUSIONS: This study illustrates that SCFAs contribute to excessive production of IL-8 in CF airways colonized with anaerobes via upregulated GPR41.

WS02.7 Initial and chronic MRSA infection in cystic fibrosis

Objectives Chronic MRSA infection, which affects approximately 26% of CF patients in the USA, is associated with declining lung function and poor outcomes (Dasenbrook, 2010). Anaerobic niches have been described within the CF lung, potentially influencing the virulence of MRSA. This study aims to compare initial and chronic CF MRSA isolates, following aerobic and anaerobic culture. Methods Isolates, obtained from CF sputum at first isolation [“early” (n = 10)] or up to 5 years later, during chronic infection [“late” (n = 15)] were cultured in aerobic and anaerobic conditions. Differences in virulence were compared using the Galleria mellonella infection model. Biofilm formation of each isolate was assessed following staining with crystal violet. Production of Δ-haemolysin (Δ-hly), a surrogate marker for expression of the virulence regulator agr, was determined by haemolysis assay. Results MRSA grown in anaerobic conditions had significantly increased virulence in the G. mellonella model (p = 0.007), increased biofilm formation (p = 0.006) and increased Δ-hly production (p<0.0001). No significant difference between Δ-hly production or biofilm formation were observed between early and late isolates; however late isolates were found to be more virulent in the G. mellonella model (p = 0.0002). Conclusion These results suggest that an anaerobic environment, as found in the CF lung, may increase virulence of MRSA and aid in the establishment of chronic infection. Further clinical studies are required to determine how these phenotypic changes are associated with transition to chronic infection and patient outcome.

Frequency of deletion 508 among Irish cystic fibrosis patients

We estimate the incidence of cystic fibrosis in Ireland to be at least 1 case per 1838 live births. We have analysed DNA from 44 Irish CF patients for the presence of deletion 508, using the polymerase chain reaction. The deletion was found in 76% of their chromosomes, and approximately 58% of the patients are homozygous for this deletion. Our results are not significantly different from those found in Canadian or UK patient populations, in which frequencies are higher than those found in Southern European countries.

Physical activity assessment in cystic fibrosis: A position statement

Background

The aim of this position statement was to inform the choice of physical activity tools for use within CF research and clinical settings.

Methods

A systematic review of physical activity tools to explore evidence for reliability, validity, and responsiveness. Narrative answers to “four key questions” on motion sensors, questionnaires and diaries were drafted by the core writing team and then discussed at the Exercise Working Group in ECFS Lisbon 2013.

Results and summary

Our current position is that activity monitors such as SenseWear or ActiGraph offer informed choices to facilitate a comprehensive assessment of physical activity, and should as a minimum report on dimensions of physical activity including energy expenditure, step count and time spent in different intensities and sedentary time. The DigiWalker pedometer offers an informed choice of a comparatively inexpensive method of obtaining some measurement of physical activity. The HAES represents an informed choice of questionnaire to assess physical activity. There is insufficient data to recommend the use of one diary over another. Future research should focus on providing additional evidence of clinimetric properties of these and new physical activity assessment tools, as well as further exploring the added value of physical activity assessment in CF.