Cystic Fibrosis Research Research Articles

Cystic fibrosis in the year 2020: A disease with a new face.

The autosomal recessive disease cystic fibrosis (CF) was once untreatable and deadly in childhood, but now most patients survive to adulthood. Many countries have instituted CF newborn screening because early diagnosis improves outcome. CF research has greatly intensified following the discovery of the CF transmembrane conductance regulator (CFTR) gene, which has more than 2000 different mutations. For patients with common mutations like F508del, CFTR modulators are life transforming and may even prevent major complications if started early in childhood. For some patients with rare CFTR mutations, a treatment path still needs to be developed. Conclusion: This review provides a general update on CF, including screening and current and future treatment.

$500 million set for cystic fibrosis research

With the launch of the cystic fibrosis drug Trikafta, about 90% of people with the disease have a treatment. The Cystic Fibrosis Foundation has an ambitious plan to close the gap and go beyond trea...

Approaching two decades of cystic fibrosis research in Qatar: a historical perspective and future directions

Cystic fibrosis (CF) is a genetic disease caused by a defect of CF transmembrane conductance regulator (CFTR) gene. CF affects multiple systems, predominantly with respiratory involvement. In Qatar, researchers have been exploring various aspects of the disease for almost 20 years. PubMed and Google Scholar were reviewed for articles related to CF in Qatar. The first publication appeared in the year 2000. Since then, several studies have been conducted on CF patients in Qatar considering a variety of topics. The presence of the CFTR I1234V mutation in a certain Arab tribe stands out as a distinguishing characteristic of CF patients in Qatar when compared to the larger Arab region or even worldwide. We aim here to summarize the existing CF research conducted in Qatar over the years as well as to introduce topics for future research.

Assessing cell-specific effects of genetic variations using tRNA microarrays

BackgroundBy definition, effect of synonymous single-nucleotide variants (SNVs) on protein folding and function are neutral, as they alter the codon and not the encoded amino acid. Recent examples indicate tissue-specific and transfer RNA (tRNA)-dependent effects of some genetic variations arguing against neutrality of synonymous SNVs for protein biogenesis.ResultsWe performed systematic analysis of tRNA abunandance across in various models used in cystic fibrosis (CF) research and drug development, including Fischer rat thyroid (FRT) cells, patient-derived primary human bronchial epithelia (HBE) from lung biopsies, primary human nasal epithelia (HNE) from nasal curettage, intestinal organoids, and airway progenitor-directed differentiation of human induced pluripotent stem cells (iPSCs). These were compared to an immortalized CF bronchial cell model (CFBE41o−) and two widely used laboratory cell lines, HeLa and HEK293. We discovered that specific synonymous SNVs exhibited differential effects which correlated with variable concentrations of cognate tRNAs.ConclusionsOur results highlight ways in which the presence of synonymous SNVs may alter local kinetics of mRNA translation; and thus, impact protein biogenesis and function. This effect is likely to influence results from mechansistic analysis and/or drug screeining efforts, and establishes importance of cereful model system selection based on genetic variation profile.

WS18-1 Multi-professional expertise and high performance informatics infrastructure supports innovative health technology research and clinical care in cystic fibrosis: Project Fizzyo

WS18-1 Multi-professional expertise and high performance informatics infrastructure supports innovative health technology research and clinical care in cystic fibrosis: Project Fizzyo

Cystic fibrosis year in review 2018, part 2.

Cystic fibrosis (CF) research and case reports were robust in the year 2018. This report summarizes publications related the multisystem effects of CF, pulmonary exacerbations, new and expanded therapies other than cystic fibrosis transmembrane conductance regulator modulator studies, and patient-reported priorities and outcomes.

Cystic fibrosis year in review 2018, part 1.

Cystic fibrosis research and case reports were robust in the year 2018. This report summarizes research and cases related to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) modulator therapies, inflammation and infection, epidemiology and the physiologic, and imaging assessment of disease.

Health State Utility Data in Cystic Fibrosis: A Systematic Review.

IntroductionCystic fibrosis (CF) is a life-limiting, hereditable condition, with the highest prevalence in Europe. CF treatments have led to improvements in clinical symptoms, disease management and decelerated disease progression. However, little is known about the health state utility (HSU) associated with CF disease states, adverse events, and changes in disease severity. Although HSU data have contributed to existing health economic modelling studies, a lack of such data have been highlighted. This systematic review aims to provide a summary of HSU-related research in CF and highlight related research gaps.MethodsOnline searches were performed in six databases and studies in any of the following categories were included: (1) estimation of HSUs in CF; (2) mapping studies between patient-reported outcome measures (PROMs) and HSUs; (3) economic evaluations on the management of CF that report primary HSU data; and (4) any CF clinical trial that reported HSU as an outcome.ResultsA total of 17 studies were reviewed, of which 12 provided HSU values for specific CF populations. The remaining five articles provided HSU data that were broken down by CF relevant health states, including lung transplantations, pulmonary exacerbation (PEx) events and forced expiratory volume in 1 s (FEV1).ConclusionCurrent HSU data in CF are limited and there is considerable scope for further research, both in providing HSU values for CF and in investigating methods for HSU elicitation/evaluation in CF populations.Electronic supplementary materialThe online version of this article (10.1007/s41669-019-0144-1) contains supplementary material, which is available to authorized users.

Results from an online survey of adults with cystic fibrosis: Accessing and using life expectancy information.

Cystic fibrosis (CF) is the one of the most common inherited diseases. It affects around 10,000 people in the UK, and the median survival age is 47. Recent developments making use of longitudinal patient registry data are producing more detailed and relevant information about predicted life expectancy in CF based on current age and clinical measurements. The objective of this study was toconduct an online survey of adults with CF living in the UK using a web-based questionnaire to investigate: (i) if and how they access information on life expectancy; (ii) what they use it for; (iii) if they want more personalised information on life expectancy or the time until other milestones. The survey was advertised through the Cystic Fibrosis Trust using social media. There were 85 respondents, covering men (39%) and women (61%) aged 16–65. 75% had received information on life expectancy either from their CF care team (34%) or other sources (71%), the most common being the Cystic Fibrosis Trust website and research literature. Most people who received information found it to be beneficial and reported using it in a variety of ways, including to plan strategies for maintaining as best health as possible and to psychologically manage current health status. 82% of respondents were interested in more personalised information about their life expectancy, and participants also noted interest in other outcomes, including time to needing transplant or reaching a low level of lung function. Themes arising in text responses included the importance of good communication of information, the difficulty of relating general information to one’s own circumstances, and a desire for increased information on factors that impact on survival in CF. As an outcome from this work, research is underway to establish how information on life expectancy can be presented to people with CF in an accessible way.

The Proceedings of the 16th Italian Convention of Investigators in Cystic Fibrosis

Every year, the Italian Cystic Fibrosis Research Foundation (FFC) brings together all its funded researchers from across Italy and beyond, in a Convention where results from FFC projects are shared and debated. These projects are either newly funded, on-going or recently concluded research. The Proceedings of the 16th Convention of Italian Investigators in Cystic Fibrosis is a supplement of Multidisciplinary Respiratory Medicine reporting results of completed projects which were presented at the FFC 2018 Convention.

The Proceedings of the 16th Italian Convention of Investigators in Cystic Fibrosis

Verona, Italy. 22-24 November 2018Every year, the Italian Cystic Fibrosis Research Foundation (FFC) brings together all its funded researchers from across Italy and beyond, in a Convention where results from FFC projects are shared and debated. These projects are either newly funded, on-going or recently concluded research. The Proceedings of the 16th Convention of Italian Investigators in Cystic Fibrosis is a supplement of Multidisciplinary Respiratory Medicine reporting results of completed projects which were presented at the FFC 2018 Convention.

Animal Models in the Pathophysiology of Cystic Fibrosis.

Our understanding of the multiorgan pathology of cystic fibrosis (CF) has improved impressively during the last decades, but we still lack a full comprehension of the disease progression. Animal models have greatly contributed to the elucidation of specific mechanisms involved in CF pathophysiology and the development of new therapies. Soon after the cloning of the CF transmembrane conductance regulator (CFTR) gene in 1989, the first mouse model was generated and this model has dominated in vivo CF research ever since. Nonetheless, the failure of murine models to mirror human disease severity in the pancreas and lung has led to the generation of larger animal models such as pigs and ferrets. The following review presents and discusses data from the current animal models used in CF research.

The effect of premature termination codon mutations on CFTR mRNA abundance in human nasal epithelium and intestinal organoids: a basis for read‐through therapies in cystic fibrosis

A major challenge in cystic fibrosis (CF) research is applying mutation-specific therapy to individual patients with diverse and rare CF transmembrane conductance regulator (CFTR) genotypes. Read-through agents are currently the most promising approach for Class I mutations that introduce premature termination codons (PTCs) into CFTR mRNA. However, variations in degradation of PTC containing transcripts by nonsense mediated decay (NMD) might lower read-through efficacy. Allele specific quantitative real time (qRT)-PCR was used to measure variations in CFTR mRNA abundance for several PTC mutations in respiratory cells and intestinal organoids. The majority of PTC mutations were associated with reduced levels of relative mRNA transcript abundance (∼33% and 26% of total CFTR mRNA in respiratory cells and intestinal organoids, respectively, compared to >50% for non-PTC causing mutations). These levels were generally not affected by PTC mutation type or position, but there could be twofold variations between individuals bearing the same genotype. Most PTC mutations in CFTR are subject to similar levels of NMD, which reduce but do not abolish PTC bearing mRNAs. Measurement of individual NMD levels in intestinal organoids and HNE cells might, therefore, be useful in predicting efficacy of PTC read-through in the context of personalized CFTR modulator therapy.

SWATH label-free proteomics for cystic fibrosis research

BackgroundLabel-free proteomics is a powerful tool for biological investigation. The SWATH protocol, relying on the Pan Human ion library, currently represents the state-of-the-art methodology for this kind of analysis. We recently discovered that this tool is not perfectly suitable for proteomics research in the CF field, as it lacks assays for several proteins crucial for the CF biology, including CFTR. MethodsWe extensively investigated the proteome of a very popular model for in vitro research on CF, CFBE41o-, and we used the corresponding data to improve the power of SWATH proteomics for CF investigation. We then used this improved tool to explore in depth the proteome of primary bronchial epithelial (BE) cells deriving from four CF individuals compared with that of four corresponding non-CF controls. By means of advanced bioinformatics tools, we outlined the presence of a number of protein networks being significantly altered by CF. ResultsOur analysis on patients' BE cells identified 154 proteins dysregulated by the CF pathology (94 upregulated and 60 downregulated). Some known CFTR interactors are present among them, but our analysis also revealed the alteration of other proteins not previously known to be related with CF. ConclusionsThe present work outlines the power of SWATH label free proteomics applied to CF research.

Cystic Fibrosis: Translating Molecular Mechanisms into Effective Therapies.

Cystic fibrosis is a genetic disease that affects approximately 75,000 individuals around the world. Long regarded as a lethal and life-limiting disease, with the most severe manifestations expressed in the progressive decline of lung function, treatment advances focusing on airway clearance and management of chronic lung infection have resulted in improved outcomes for individuals with cystic fibrosis. These advances have been realized in conjunction with an improved understanding of the genetic basis of this disease, dating back to the discovery of the cystic fibrosis gene in 1989. The identification of the cystic fibrosis gene and the advancement of our understanding of the resultant cystic fibrosis transmembrane conductance regulator protein have led to the development of a new class of cystic fibrosis therapies designed to directly impact the function of this protein. These therapeutic developments have progressed, targeting the various mutations that can cause cystic fibrosis. These new medications, known as cystic fibrosis transmembrane conductance regulator modulators, have changed the landscape of cystic fibrosis care and cystic fibrosis research. Their demonstrated effect in patients with specific cystic fibrosis mutations has ignited the hope that such therapies will soon be available to more individuals with this disease, moving the cystic fibrosis community significantly closer to the ultimate goal of curing this disease.

Establishment of a ΔF508-CF promyelocytic cell line for cystic fibrosis research and drug screening

Cystic fibrosis (CF), one of the most common genetic disorders, is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. In spite of significant improvement in patient life expectancy, the disease remains lethal and incurable. Clinically, CF lung disease claims the most morbidity and mortality, characterized by chronic bacterial infection, persistent neutrophilic inflammation, and purulent small airway obstruction. Although all these manifestations are highly associated with neutrophils, the actual role of this phagocyte in the disease pathogenesis has not been fully appreciated. One of the major obstacles impeding such progress is the lack of CF neutrophil cell lines. Taking advantage of the new CRISPR/Cas9 gene-editing technology, we have generated a homozygous ΔF508-CF promyelocytic cell line from HL-60 cells, from which unlimited CF neutrophil cells can be differentiated. The derived cells showed defective CFTR presentation, deficient phagosomal hypochlorous acid (HOCl) production, and compromised microbial killing. Such a phenotype recapitulates that of primary neutrophils from CF patients. Thus, the established human CF promyelocytic cell line should be a useful tool for future CF basic research and drug screening.

Expression and function of Anoctamin 1/TMEM16A calcium-activated chloride channels in airways of in vivo mouse models for cystic fibrosis research.

Physiological processes of vital importance are often safeguarded by compensatory systems that substitute for primary processes in case these are damaged by gene mutation. Ca2+-dependent Cl- secretion in airway epithelial cells may provide such a compensatory mechanism for impaired Cl- secretion via cystic fibrosis transmembrane conductance regulator (CFTR) channels in cystic fibrosis (CF). Anoctamin 1 (ANO1) Ca2+-gated Cl- channels are known to contribute to calcium-dependent Cl- secretion in tracheal and bronchial epithelia. In the present study, two mouse models of CF were examined to assess a potential protective function of Ca2+-dependent Cl- secretion, a CFTR deletion model (cftr-/-), and a CF pathology model that overexpresses the epithelial Na+ channel β-subunit (βENaC), which is encoded by the Scnn1b gene, specifically in airway epithelia (Scnn1b-Tg). The expression levels of ANO1 were examined by mRNA and protein content, and the channel protein distribution between ciliated and non-ciliated epithelial cells was analyzed. Moreover, Ussing chamber experiments were conducted to compare Ca2+-dependent Cl- secretion between wild-type animals and the two mouse models. Our results demonstrate that CFTR and ANO1 channels were co-expressed with ENaC in non-ciliated cells of mouse tracheal and bronchial epithelia. Ciliated cells did not express these proteins. Despite co-localization of CFTR and ANO1 in the same cell type, cells in cftr-/- mice displayed no altered expression of ANO1. Similarly, ANO1 expression was unaffected by βENaC overexpression in the Scnn1b-Tg line. These results suggest that the CF-related environment in the two mouse models did not induce ANO1 overexpression as a compensatory system.

Challenges and Promises for Planning Future Clinical Research Into Bacteriophage Therapy Against Pseudomonas aeruginosa in Cystic Fibrosis. An Argumentative Review.

Although early aggressive and prolonged treatment with specific antibiotics can extend survival in patients with cystic fibrosis (CF) colonized by opportunistic Pseudomonas aeruginosa (PA), antibiotics fail to eradicate the infecting multidrug-resistant (MDR) PA strains in CF. Century-long research has suggested treating patients with bacteriophages (phages, prokaryotic viruses) naturally hosted by bacteria. Although the only phage types used in therapy, lytic phages, lyse PA aggregated in biofilm matrix by depolymerase degrading enzymes, how they can effectively, safely, and persistently do so in patients with CF is unclear. Even though advanced techniques for formulating phage cocktails, training phages and collecting phage libraries have improved efficacy in vitro, whether personalized or ready-to-use therapeutic approaches or phages and antibiotics combined are effective and safe in vivo, and can reduce PA biofilms, remains debatable. Hence, to advance clinical research on phage therapy in clinical trials, also involving mucoid and non-mucoid multidrug-resistant PA in CF, and overcome problems in Western international regulations, we need reliable and repeatable information from experiments in vitro and in vivo on phage characterization, cocktail selection, personalized approaches, and phages combined with antibiotics. These findings, challenges, and promises prompted us to undertake this argumentative review to seek up-to-date information from papers describing lytic phage activity tested in vitro on PA laboratory strains, and PA strains from chronic infections including CF. We also reviewed in vivo studies on phage activity on pulmonary and non-pulmonary animal host models infected by laboratory or CF PA strains. Our argumentative review provides essential information showing that future phage clinical research in CF should use well-characterized and selected phages isolated against CF PA, tested in vitro under dynamic conditions in cocktails or combined with antibiotics, and in vivo on non-pulmonary and pulmonary host models infected with mucoid and non-mucoid CF MDR PA. Our findings should encourage pharmaceutical industries to conduct clinical trials in vitro and in vivo testing patented genomic engineered phages from phage libraries combined with antibiotics to treat or even prevent multidrug-resistant PA in CF, thus helping international regulatory agencies to plan future clinical research on phage therapy in CF.

Highlights from the 2017 North American Cystic Fibrosis Conference.

The 31st annual North American Cystic Fibrosis Conference (NACFC) was held in Indianapolis, IN on November 2-4, 2017. Abstracts of presentations from the conference were published in a supplement to Pediatric Pulmonology [2017; Pediatr Pulmonol Suppl. 52: S1-S776]. The current review summarizes several major topic areas addressed at the conference: the pathophysiology and basic science of cystic fibrosis (CF) lung disease, clinical trials, clinical management issues, and quality improvement (QI). In this review, we describe emerging concepts in several areas of CF research and care.

Concurrent Airway Surface Liquid Absorption and Secretion in Human Bronchioles

Characterization of epithelial fluid and electrolyte transport in native small airway epithelia has been largely neglected due to the complex tissue architecture as well as by its inaccessibility and lack of applicable assays, especially in human tissues. To better understand how airway surface liquid (ASL) is maintained as a balance between absorbing and secreting functions, we measure ion transport properties of bronchioles with diameters of 1–2 mm isolated from freshly resected specimens of human lungs with a “mini”‐Ussing chamber (area≈1 mm2). We determined the effects of inhibiting absorption by applying amiloride to inhibit Na+ conductance through ENaC and secretion by applying bumetanide to inhibit the Na+‐K+‐2Cl− cotransporter to block Cldependent secretion demonstrated spontaneous absorptive as well as secretory short circuit currents in bilateral 150 mM NaCl‐Ringer solution. We also tested for the presence of the Clchannels, CFTR stimulating with Fsk/IBMX and CaCC with UTP. Both agonists independently stimulated additive equivalent short circuit current in the same specimen of small airway tissue, but evoked distinctly opposite effects on the transepithelial potential (Vt). While Fsk/IBMX (cAMP) activation depolarized Vt, UTP (Ca2+) stimulation hyperpolarized the Vt. The depolarization of Vt induced by cAMP suggests that activating CFTR may stimulate fluid absorption, while hyperpolarization of Vt by Ca2+ (UTP) suggest that activating CaCC may stimulate fluid secretion. Independent regulation of these fluid movements may be critical to regulation of ASL volume during conditions of stress. Human small airways constitutively and concurrently secrete and absorb fluid, structurally separated and independent epithelial cells for liquid secretion and absorption. Our results present new evidence for how the delicate layer of fluid lining the small airways is physiologically maintained in a steady state and appropriate airway hydration.Support or Funding InformationThe Nancy Olmsted Trust and the Cystic Fibrosis Research Inc. (CFRI).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.