Lung transplantation for cystic fibrosis: an update

Disease-related blood-based differential methylation in cystic fibrosis and its representation in lung cancer revealed a regulatory locus in PKP3 in lung epithelial cells

Cystic fibrosis (CF) is a monogenic disease, characterized by massive chronic lung inflammation. The observed variability in clinical phenotypes in monozygotic CF twins is likely associated with the extent of inflammation. This study sought to investigate inflammation-related aberrant DNA methylation in CF twins and to determine to what extent acquired methylation changes may be associated with lung cancer.

Blood-based genome-wide DNA methylation analysis was performed to compare the DNA methylomes of monozygotic twins, from the European CF Twin and Sibling Study with various degrees of disease severity. Putatively inflammation-related and differentially methylated positions were selected from a large lung cancer case-control study and investigated in blood by targeted bisulphite next-generation-sequencing. An inflammation-related locus located in the Plakophilin-3 (PKP3) gene was functionally analysed regarding promoter and enhancer activity in presence and absence of methylation using luciferase reporter assays.

We confirmed in a unique cohort that monozygotic twins, even if clinically discordant, have only minor differences in global DNA methylation patterns and blood cell composition. Further, we determined the most differentially methylated positions, a high proportion of which are blood cell-type-specific, whereas others may be acquired and thus have potential relevance in the context of inflammation as lung cancer risk factors. We identified a sequence in the gene body of PKP3 which is hypermethylated in blood from CF twins with severe phenotype and highly variably methylated in lung cancer patients and controls, independent of known clinical parameters, and showed that this region exhibits methylation-dependent promoter activity in lung epithelial cells.

[Functional endoscopic sinus surgery in a patient with cystic fibrosis after lung transplantation]

Cystic fibrosis is genetic multisystem disorder with a predominant lesion of the respiratory tract. The duration and quality of life of these patients depends on the state of respiratory function. Progressive lung dysfunction is still the leading cause of mortality patients with cystic fibrosis. End-stage lung diseases in patients with cystic fibrosis, lung transplantation is a viable method of treatment. It has the ability to prolong life of these patients. Survival in cystic fibrosis has steadily increased medical treatment and post-transplant. Chronic rhinosinusitis (with nasal polys and without) impacts almost all cystic fibrosis patients, leading to significant reductions in quality of life. Chronic rhinosinusitis with nasal polyps is prevalent in the cystic fibrosis patients, and it is often a recalcitrant infection with multidrug resistant organisms. Medical therapies such as nasal irrigations, nasal steroids, and antibiotics are critical for managing symptoms, but functional endoscopic sinus surgery is necessary for refractory cases. The unified airway hypothesis suggests that sanitation bacterial infection in the upper airway can also decrease bacterial burden in the lungs. The article presents a clinical case of successful endoscopic sinus surgery in a 15-year-old patient with chronic rhinosinusitis with nasal polyps and cystic fibrosis after lung transplantation. The intervention was performed under General anesthesia and controlled hypotension. Bilateral antrostomy, ethmoidectomy and Draf IIb frontal sinusotomy were performed by endoscopic endonasal approach. There were no intra - and post-operative rhinosurgical or lung complications. The follow-up period was 18 months. At present, there is no relapse of chronic polypous rhinosinusitis, and there are no indications for revision intervention.

Cryptides Identified in Human Apolipoprotein B as New Weapons to Fight Antibiotic Resistance in Cystic Fibrosis Disease

Chronic respiratory infections are the main cause of morbidity and mortality in cystic fibrosis (CF) patients, and are characterized by the development of multidrug resistance (MDR) phenotype and biofilm formation, generally recalcitrant to treatment with conventional antibiotics. Hence, novel effective strategies are urgently needed. Antimicrobial peptides represent new promising therapeutic agents. Here, we analyze for the first time the efficacy of three versions of a cryptide identified in human apolipoprotein B (ApoB, residues 887-922) towards bacterial strains clinically isolated from CF patients. Antimicrobial and anti-biofilm properties of ApoB-derived cryptides have been analyzed by broth microdilution assays, crystal violet assays, confocal laser scanning microscopy and scanning electron microscopy. Cell proliferation assays have been performed to test cryptide effects on human host cells. ApoB-derived cryptides have been found to be endowed with significant antimicrobial and anti-biofilm properties towards Pseudomonas and Burkholderia strains clinically isolated from CF patients. Peptides have been also found to be able to act in combination with the antibiotic ciprofloxacin, and they are harmless when tested on human bronchial epithelial mesothelial cells. These findings open interesting perspectives to cryptide applicability in the treatment of chronic lung infections associated with CF disease.

Lung transplantation for cystic fibrosis

BACKGROUND

The contribution of lung transplantation to the treatment of patients with end-stage cystic fibrosis (CF) has been debated. We aimed to describe achievable outcomes from high-volume CF and lung transplant programs. This study reports on the largest single-center experience of lung transplantation for adult and pediatric patients with CF. It also highlights the evolution of practice and outcomes over time.

METHODS

A retrospective analysis of the prospectively collected Toronto Lung Transplant database was carried out. Post-transplant survival in CF was calculated using the Kaplan-Meier method and analyzed with log-rank tests.

RESULTS

From 1983 to 2016, a total of 1,885 transplants were performed at our institution, where 364 (19.3%) were CF recipients and another 39 (2.1%) were CF retransplants. The mean age at first transplant was 29.5 ± 9.7 years where 56.6% were males and 91.5% were adults. Pre-transplantation, 88 patients (24.2%) were Burkholderia cepacia complex (BCC)-positive, 143 (39.3%) had diabetes mellitus, and the mean forced expiratory volume in one second was 26.0 ± 7.2%, as predicted at listing. The 1-, 5-, and 10-year probabilities of survival in adults who were BCC-negative were 94%, 70%, and 53%, respectively. Pediatric, BCC-positive, and retransplant recipients had worse survival than adult patients who were BCC-negative. Strategies to improve the donor pool did not affect survival but possibly reduced waitlist mortality. For the entire cohort, the most common causes of death after lung transplant were infection and chronic lung allograft dysfunction.

CONCLUSIONS

Lung transplantation for CF provides excellent short- and long-term outcomes. These results strongly support lung transplantation as the standard of care for patients with CF having advanced lung disease.

Ex Vivo Lung Perfusion: A Review of Research and Clinical Practices

End-stage lung disease is ultimately treated with lung transplantation. However, there is a paucity of organs with an increasing number of patients being diagnosed with end-stage lung disease. Ex vivo lung perfusion has emerged as a potential tool to assess the quality and to recondition marginal donor lungs prior to transplantation with the goal of increasing the donor pool. This technology has shown promise with similar results compared with the conventional technique of cold static preservation in terms of primary graft dysfunction and overall outcomes. This review provides an update on the results and uses of this technology. The review will also summarize clinical studies and techniques in reconditioning and assessing lungs on ex vivo lung perfusion. Last, we discuss how this technology can be applied to fields outside of transplantation such as thoracic oncology and bioengineering.

Innovative Therapies for Cystic Fibrosis: The Road from Treatment to Cure

Cystic fibrosis (CF), a life-threatening multiorgan genetic disease, is facing a new era of research and development using innovative gene-directed personalized therapies. The priority organ to cure is the lung, which suffers recurrent and chronic bacterial infection and inflammation since infancy, representing the main cause of morbidity and precocious mortality of these individuals. After the disappointing failure of gene-replacement approaches using gene therapy vectors, no single drug is presently available to repair all the CF gene defects. The impressive number of different CF gene mutations is now tackled with different chemical and biotechnological tools tailored to the specific molecular derangements, thanks to the extensive knowledge acquired over many years on the mechanisms of CF cell and organ pathology. This review provides an overview and recalls both the successes and limitations of the different experimental approaches, such as high-throughput screening on chemical libraries to discover CF gene correctors and potentiators, dual-acting compounds, read-through molecules, splicing defect repairing tools, cystic fibrosis transmembrane conductance regulator (CFTR) "amplifiers," CFTR interactome modulators and the first gene editing attempts.

Mortality Due to Cystic Fibrosis over a 36-Year Period in Spain: Time Trends and Geographic Variations

The aim of this study is to analyze population-based mortality attributed to cystic fibrosis (CF) over 36 years in Spain. CF deaths were obtained from the National Statistics Institute, using codes 277.0 from the International Classification of Diseases (ICD) ninth revision (ICD9-CM) and E84 from the tenth revision (ICD10) to determine the underlying cause of death. We calculated age-specific and age-adjusted mortality rates, and time trends were assessed using joinpoint regression. The geographic analysis by district was performed by standardized mortality ratios (SMRs) and smoothed-SMRs. A total of 1002 deaths due to CF were identified (50.5% women). Age-adjusted mortality rates fell by −0.95% per year between 1981 and 2016. The average age of death from CF increased due to the annual fall in the mortality of under-25s (−3.77% males, −2.37% females) and an increase in over-75s (3.49%). We identified districts with higher than expected death risks in the south (Andalusia), the Mediterranean coast (Murcia, Valencia, Catalonia), the West (Extremadura), and the Canary Islands. In conclusion, in this study we monitored the population-based mortality attributed to CF over a long period and found geographic differences in the risk of dying from this disease. These findings complement the information provided in other studies and registries and will be useful for health planning.

Molecular basis of cystic fibrosis: from bench to bedside

Cystic fibrosis (CF), is an autosomal recessive disease affecting different organs. The lung disease, characterized by recurrent and chronic bacterial infection and inflammation since infancy, is the main cause of morbidity and precocious mortality of these individuals. The innovative therapies directed to repair the defective CF gene should account for the presence of more than 200 disease-causing mutations of the CF transmembrane conductance regulator (CFTR) gene. The review will recall the different experimental approaches in discovering CFTR protein targeted molecules, such as the high throughput screening on chemical libraries to discover correctors and potentiators of CFTR protein, dual-acting compounds, read-through molecules, splicing defects repairing tools, CFTR "amplifiers".

Pediatric lung transplantation and end of life care in cystic fibrosis: Barriers and successful strategies

Pediatric lung transplantation has advanced over the years, providing a potential life-prolonging therapy to patients with cystic fibrosis. Despite this, many challenges in lung transplantation remain and result in worse outcomes than other solid organ transplants. As CF lung disease progresses, children and their caregivers are often simultaneously preparing for lung transplantation and end of life. In this article, we will discuss the current barriers to success in pediatric CF lung transplantation as well as approaches to end of life care in this population.

Burkholderia cenocepacia Infections in Cystic Fibrosis Patients: Drug Resistance and Therapeutic Approaches

Burkholderia cenocepacia is an opportunistic pathogen particularly dangerous for cystic fibrosis (CF) patients. It can cause a severe decline in CF lung function possibly developing into a life-threatening systemic infection known as cepacia syndrome. Antibiotic resistance and presence of numerous virulence determinants in the genome make B. cenocepacia extremely difficult to treat. Better understanding of its resistance profiles and mechanisms is crucial to improve management of these infections. Here, we present the clinical distribution of B. cenocepacia described in the last 6 years and methods for identification and classification of epidemic strains. We also detail new antibiotics, clinical trials, and alternative approaches reported in the literature in the last 5 years to tackle B. cenocepacia resistance issue. All together these findings point out the urgent need of new and alternative therapies to improve CF patients’ life expectancy.