Factors associated with receiving CF care and use of telehealth in 2020 among persons with Cystic Fibrosis in the United States.

BACKGROUND: The COVID-19 pandemic resulted in the use of telehealth to deliver the cystic fibrosis (CF) care model, which recommends routine follow-up for monitoring of nutritional status, bacterial culture surveillance, pulmonary function testing, and screening for CF-related complications such as diabetes or osteoporosis. METHODS: The objective of this study was to use Cystic Fibrosis Foundation Patient Registry (CFFPR) data to quantify the extent to which persons with CF received the recommended components of the care model in 2019 versus 2020. A risk factor analysis was implemented to identify patient characteristics associated with attaining the recommended CF care and use of any telehealth using multivariable logistic regression. RESULTS: A total of 28,132 CFFPR participants were included in the study. The proportion of individuals meeting the recommendations for CF care was lower in 2020 for every indicator, and lower in adults compared to children. In adults, demographic, socioeconomic and CF-related disease covariates were significantly associated with both achieving an aggregate level of care and use of telehealth. In the pediatric population, minority race/ethnicity and markers of lower socioeconomic status were associated with a lower odds of telehealth use. In all analyses, having received the recommended level of care in 2019 was associated with a higher odds of both reported telehealth use and achieving the recommended elements of the CF care model in 2020. CONCLUSION: Fewer participants met recommendations for care in 2020 despite widespread use of telehealth, and use of telehealth did not equate to adherence to all aspects of CF care.

Furin as a therapeutic target in cystic fibrosis airways disease.

Clinical management of cystic fibrosis (CF) has been greatly improved by the development of small molecule modulators of the CF transmembrane conductance regulator (CFTR). These drugs help to address some of the basic genetic defects of CFTR; however, no suitable CFTR modulators exist for 10% of people with CF (PWCF). An alternative, mutation-agnostic therapeutic approach is therefore still required. In CF airways, elevated levels of the proprotein convertase furin contribute to the dysregulation of key processes that drive disease pathogenesis. Furin plays a critical role in the proteolytic activation of the epithelial sodium channel; hyperactivity of which causes airways dehydration and loss of effective mucociliary clearance. Furin is also responsible for the processing of transforming growth factor-ß, which is increased in bronchoalveolar lavage fluid from PWCF and is associated with neutrophilic inflammation and reduced pulmonary function. Pathogenic substrates of furin include Pseudomonas exotoxin A, a major toxic product associated with Pseudomonas aeruginosa infection and the spike glycoprotein of severe acute respiratory syndrome coronavirus 2, the causative pathogen for coronavirus disease 2019. In this review we discuss the importance of furin substrates in the progression of CF airways disease and highlight selective furin inhibition as a therapeutic strategy to provide clinical benefit to all PWCF.

Impact of elexacaftor/tezacaftor/ivacaftor on depression and anxiety in cystic fibrosis.

BACKGROUND: Cystic fibrosis (CF) is associated with worsening of depression and anxiety symptoms. Elexacaftor/tezacaftor/ivacaftor (Trikafta®), a cystic fibrosis transmembrane regulator (CFTR) modulator approved in 2019, significantly improves lung function, decreases pulmonary exacerbations, and improves quality of life. Studies are needed to evaluate the effects of Trikafta on symptoms of anxiety and depression. RESEARCH QUESTION: Do adults with CF report a change in depression and anxiety symptoms after Trikafta initiation? STUDY DESIGN AND METHODS: A retrospective chart review was conducted of patients with CF (n = 127) receiving care from January 2015 through February 2022. Data collected included demographics, annual PHQ-9 and GAD-7 scores, FEV1 percent predicted at each visit, BMI, consistency and timeline of Trikafta use, mental health diagnoses, counseling/psychotherapy use, psychiatric medication use, prescriber of psychiatric medications, number of psychiatric emergency department visits and psychiatric hospital admissions, and sleep disturbances. RESULTS: Of the 127 patients screened for eligibility, 100 patients were included. Data collected yielded 563 PHQ-9, 563 GAD-7, and 560 ppFEV1 data points. No significant changes in average PHQ-9 or GAD-7 scores were found after Trikafta initiation or due to the COVID-19 pandemic. However, 22% of patients initiated or had a change in psychiatric medications, and patients with changes in psychiatric medications had significantly higher PHQ-9 and GAD-7 scores than patients not prescribed psychiatric medications. Trikafta use improved lung function by an average of 5.23% (p = 8.56e-08). Around a quarter (23%) of all patients reported sleep issues after initiating Trikafta. INTERPRETATION: No significant changes in average PHQ-9 and GAD-7 scores were found after Trikafta initiation. A quarter of patients required a change in psychiatric medications, and significant differences in depression and anxiety scores were found between patients with a change in psychiatric medications and those not prescribed medication. Twenty-three percent of patients reported a prevalence of sleep issues after Trikafta initiation.

CFTR Inhibitors Display In Vitro Antiviral Activity against SARS-CoV-2.

Several reports have indicated that SARS-CoV-2 infection displays unexpected mild clinical manifestations in people with cystic fibrosis (pwCF), suggesting that CFTR expression and function may be involved in the SARS-CoV-2 life cycle. To evaluate the possible association of CFTR activity with SARS-CoV-2 replication, we tested the antiviral activity of two well-known CFTR inhibitors (IOWH-032 and PPQ-102) in wild type (WT)-CFTR bronchial cells. SARS-CoV-2 replication was inhibited by IOWH-032 treatment, with an IC50 of 4.52 µM, and by PPQ-102, with an IC50 of 15.92 µM. We confirmed this antiviral effect on primary cells (MucilAirTM wt-CFTR) using 10 µM IOWH-032. According to our results, CFTR inhibition can effectively tackle SARS-CoV-2 infection, suggesting that CFTR expression and function might play an important role in SARS-CoV-2 replication, revealing new perspectives on the mechanisms governing SARS-CoV-2 infection in both normal and CF individuals, as well as leading to potential novel treatments.

A survey assessing the impact of COVID-19 and elexacaftor/tezacaftor/ifavacaftor on both physical and mental health in adults with cystic fibrosis.

In this letter to the editor, we report 82 persons with CF (PwCF) self-reported changes in mental and physical health and potential attribution with either the COVID-19 pandemic and the initiation elexacaftor/tezacaftor/ivacaftor (ETI). Emerging evidence has shown an association with ETI and mental health adverse events. The close proximity of ETI FDA approval and prescribing in PwCF and the COVID-19 pandemic present a challenge in determining the cause of mental health decline. We report 33 (40%) of respondents felt that COVID-19 contributed to a worsening of either their anxiety, depression, or both and 7 (9%) of respondents felt that ETI contributed to a worsening in their anxiety, depression, or both. Eighteen (23%) of respondents felt that ETI had contributed to improvement their mental health. This letter highlights multiple factors that could be impacting mental health beyond ETI. As the COVID-19 pandemic is moving toward an endemic phase, future studies may have more success in deciphering ETI effects on mental health.

Impact of Digital Technologies on Clinical Care for Adults with Cystic Fibrosis.

The coronavirus disease 2019 pandemic accelerated the implementation of digital technologies, which have now become embedded as essential tools for the management of chronic disease, including cystic fibrosis (CF). Despite subsequent easing of restrictions and because of improved clinical stability resulting from the introduction of highly effective modulator therapy, digital technologies including video and telephone consultations and remote monitoring are likely to remain integral to the future delivery of CF health care. In this article, we explore some of the key developments in digital technologies, barriers to their adoption, and how the CF community is likely to embrace lessons learned from the recent pandemic to help modernize and reshape the future of CF care.

Advanced Cystic Fibrosis Lung Disease and Lung Transplantation in the Era of Cystic Fibrosis Transmembrane Conductance Regulator Modulators.

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have changed the clinical landscape of cystic fibrosis (CF) by improving clinically significant outcome measures and quality of life of people with CF (pwCF). There are now long-term data showing improved 5-year survival with the use of ivacaftor, and the field continues to evolve at a rapid pace with the continued development of highly effective CFTR modulators. While the randomized controlled trials of CFTR modulators excluded patients with severe lung disease (forced expiratory volume in 1 second <40% predicted), observational data based on case reports and registry data show similar benefits in those with advanced lung disease. This has altered clinical practice particularly as it pertains to the role of lung transplantation in CF. This article describes the impact of highly effective modulator therapy (HEMT) on the natural history of CF and the influence on the timing of referral and consideration of listing for lung transplantation. CF clinicians play a pivotal role to ensure that the impetus of the CF foundation consensus guidelines to facilitate timely referral for lung transplantation is not lost among the excitement of anticipated sustained benefit from HEMT. While the widespread availability of elexacaftor/tezacaftor/ivacaftor over the past 2 years has been associated with a sharp drop in the number of people referred for consideration for lung transplantation and the number of people wait-listed for lung transplantation, it is difficult to accurately determine the true impact due to the confounding effect of the coronavirus disease 2019 pandemic. It is expected that lung transplantation will remain an important treatment for a smaller number of pwCF. Lung transplantation offers survival benefits in CF, and there remains an imperative to ensure timely consideration of lung transplantation in patients with advanced disease to further reduce the number of pwCF dying without consideration of lung transplant.

Suicide attempts in adolescents with cystic fibrosis on Elexacaftor/Tezacaftor/Ivacaftor therapy.

Elexacaftor/Tezacaftor/Ivacaftor (ETI) is a recently approved cystic fibrosis (CF) transmembrane conductance regulator modulator therapy that has shown promising clinical and laboratory improvements on multiple organ systems in people with CF (pwCF). While original clinical trials found little to no effect on depression and anxiety, many post-marketing reports have suggested that ETI may be associated with adverse mental health effects. Here we report on two pwCF with adverse mental health effects shortly after starting ETI. Although many factors such as the burden of living with a chronic disease or widespread effects of the Covid-19 pandemic may have contributed to these events, similar reports have led to mounting concern that ETI may be the cause of such events. Regular mental health screening before the initiation of ETI and monitoring for signs and symptoms of mental diseases afterward should be a routine part of care, given the gravity of possible outcomes.

SARS-CoV-2 viral entry and replication is impaired in Cystic Fibrosis airways due to ACE2 downregulation.

As an inherited disorder characterized by severe pulmonary disease, cystic fibrosis could be considered a comorbidity for coronavirus disease 2019. Instead, current clinical evidence seems to be heading in the opposite direction. To clarify whether host factors expressed by the Cystic Fibrosis epithelia may influence coronavirus disease 2019 progression, here we describe the expression of SARS-CoV-2 receptors in primary airway epithelial cells. We show that angiotensin converting enzyme 2 (ACE2) expression and localization are regulated by Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) channel. Consistently, our results indicate that dysfunctional CFTR channels alter susceptibility to SARS-CoV-2 infection, resulting in reduced viral entry and replication in Cystic Fibrosis cells. Depending on the pattern of ACE2 expression, the SARS-CoV-2 spike (S) protein induced high levels of Interleukin 6 in healthy donor-derived primary airway epithelial cells, but a very weak response in primary Cystic Fibrosis cells. Collectively, these data support that Cystic Fibrosis condition may be at least partially protecting from SARS-CoV-2 infection.

SARS-CoV-2-Mediated Lung Edema and Replication Are Diminished by Cystic Fibrosis Transmembrane Conductance Regulator Modulators.

Coronaviruses (CoVs) of genera α, ß, γ, and δ encode proteins that have a PDZ-binding motif (PBM) consisting of the last four residues of the envelope (E) protein (PBM core). PBMs may bind over 400 cellular proteins containing PDZ domains (an acronym formed by the combination of the first letter of the names of the three first proteins where this domain was identified), making them relevant for the control of cell function. Three highly pathogenic human CoVs have been identified to date: severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), and SARS-CoV-2. The PBMs of the three CoVs were virulence factors. SARS-CoV mutants in which the E protein PBM core was replaced by the E protein PBM core from virulent or attenuated CoVs were constructed. These mutants showed a gradient of virulence, depending on whether the alternative PBM core introduced was derived from a virulent or an attenuated CoV. Gene expression patterns in the lungs of mice infected with SARS-CoVs encoding each of the different PBMs were analyzed by RNA sequencing of infected lung tissues. E protein PBM of SARS-CoV and SARS-CoV-2 dysregulated gene expression related to ion transport and cell homeostasis. Decreased expression of cystic fibrosis transmembrane conductance regulator (CFTR) mRNA, essential for alveolar edema resolution, was shown. Reduced CFTR mRNA levels were associated with edema accumulation in the alveoli of mice infected with SARS-CoV and SARS-CoV-2. Compounds that increased CFTR expression and activity, significantly reduced SARS-CoV-2 growth in cultured cells and protected against mouse infection, suggesting that E protein virulence is mediated by a decreased CFTR expression. IMPORTANCE Three highly pathogenic human CoVs have been identified: SARS-CoV, MERS-CoV, and SARS-CoV-2. The E protein PBMs of these three CoVs were virulence factors. Gene expression patterns associated with the different PBM motifs in the lungs of infected mice were analyzed by deep sequencing. E protein PBM motif of SARS-CoV and SARS-CoV-2 dysregulated the expression of genes related to ion transport and cell homeostasis. A decrease in the mRNA expression of the cystic fibrosis transmembrane conductance regulator (CFTR), which is essential for edema resolution, was observed. The reduction of CFTR mRNA levels was associated with edema accumulation in the lungs of mice infected with SARS-CoV-2. Compounds that increased the expression and activity of CFTR drastically reduced the production of SARS-CoV-2 and protected against its infection in a mice model. These results allowed the identification of cellular targets for the selection of antivirals.

Gain- and Loss-of-Function CFTR Alleles Are Associated with COVID-19 Clinical Outcomes.

Carriers of single pathogenic variants of the CFTR (cystic fibrosis transmembrane conductance regulator) gene have a higher risk of severe COVID-19 and 14-day death. The machine learning post-Mendelian model pinpointed CFTR as a bidirectional modulator of COVID-19 outcomes. Here, we demonstrate that the rare complex allele [G576V;R668C] is associated with a milder disease via a gain-of-function mechanism. Conversely, CFTR ultra-rare alleles with reduced function are associated with disease severity either alone (dominant disorder) or with another hypomorphic allele in the second chromosome (recessive disorder) with a global residual CFTR activity between 50 to 91%. Furthermore, we characterized novel CFTR complex alleles, including [A238V;F508del], [R74W;D1270N;V201M], [I1027T;F508del], [I506V;D1168G], and simple alleles, including R347C, F1052V, Y625N, I328V, K68E, A309D, A252T, G542*, V562I, R1066H, I506V, I807M, which lead to a reduced CFTR function and thus, to more severe COVID-19. In conclusion, CFTR genetic analysis is an important tool in identifying patients at risk of severe COVID-19.

CFTR pharmacological modulators: A great advance in cystic fibrosis management.

Cystic fibrosis is a severe monogenic disease that affects around 7400 patients in France. More than 2100 mutations in the cystic fibrosis conductance transmembrane regulator (CFTR), the gene encoding for an epithelial ion channel that normally transports chloride and bicarbonate, lead to mucus dehydration and impaired bronchial clearance. Systematic neonatal screening in France since 2002 has enabled early diagnosis of cystic fibrosis. Although highly demanding, supportive treatments including daily chest physiotherapy, inhaled aerosol therapy, frequent antibiotic courses, nutritional and pancreatic extracts have improved the prognosis. Median age at death is now beyond 30 years. Ivacaftor was the first CFTR modulator found to both reduce sweat chloride concentration and improve pulmonary function in the rare CFTR gating mutations. Combinations of modulators such as lumacaftor + ivacaftor or tezacaftor + ivacaftor were found to improve pulmonary function both in patients homozygous for the F508del mutation characterized by the lack of CFTR protein and those heterozygous for F508del with minimal CFTR activity. The triple combination of ivacaftor + tezacaftor + elexacaftor was recently shown to significantly improve pulmonary function and quality of life, to normalize sweat chloride concentration, and to reduce the need for antibiotic therapy in patients with at least one F508del mutation (83% in France). These impressive data, however, need to be confirmed in the long term. Nevertheless, it is encouraging to hear treated patients testify about their markedly improved quality of life and to observe that the number of lung transplants for cystic fibrosis decreased dramatically in France after 2020, despite the COVID pandemic, with no increase in deaths without lung transplant.

Effects of hypoxia on respiratory diseases: perspective view of epithelial ion transport.

The balance of gas exchange and lung ventilation is essential for the maintenance of body homeostasis. There are many ion channels and transporters in respiratory epithelial cells, including epithelial sodium channel, Na,K-ATPase, cystic fibrosis transmembrane conductance regulator, and some transporters. These ion channels/transporters maintain the capacity of liquid layer on the surface of respiratory epithelial cells and provide an immune barrier for the respiratory system to clear off foreign pathogens. However, in some harmful external environments and/or pathological conditions, the respiratory epithelium is prone to hypoxia, which would destroy the ion transport function of the epithelium and unbalance the homeostasis of internal environment, triggering a series of pathological reactions. Many respiratory diseases associated with hypoxia manifest an increased expression of hypoxia-inducible factor-1, which mediates the integrity of the epithelial barrier and affects epithelial ion transport function. It is important to study the relationship between hypoxia and ion transport function, whereas the mechanism of hypoxia-induced ion transport dysfunction in respiratory diseases is not clear. This review focuses on the relationship between hypoxia and respiratory diseases, as well as dysfunction of ion transport and tight junctions in respiratory epithelial cells under hypoxia.

Infection control in cystic fibrosis: evolving perspectives and challenges.

PURPOSE OF REVIEW: This article reviews the impact of some of the most recent changes in clinical care management in cystic fibrosis on infection prevention practice and advice for people with cystic fibrosis. RECENT FINDINGS: People with cystic fibrosis (CF) consistently highlight infection control as one of their major concerns. Infection prevention guidance and practice has facilitated successful decreases in rates of many transmissible CF pathogens. The coronavirus disease 2019 pandemic highlighted the clinical significance of respiratory viral infections and has accelerated the implementation of remote monitoring and telemedicine consultations as standard practice in CF. The continued improvement in health of the CF population is being further augmented by the introduction of new therapies, in particular cystic fibrosis transmembrane conductance regulator modulators. Infection prevention will remain pertinent to CF care, but these recent changes in clinical practice will have ongoing implications for infection prevention guidance in CF. SUMMARY: Recent changes in CF clinical care have implications that will lead to further evolution of infection control practice and advice.

Chloride channels in the lung: Challenges and perspectives for viral infections, pulmonary arterial hypertension, and cystic fibrosis.

Fine control over chloride homeostasis in the lung is required to maintain membrane excitability, transepithelial transport as well as intra- and extracellular ion and water homeostasis. Over the last decades, a growing number of chloride channels and transporters have been identified in the cells of the pulmonary vasculature and the respiratory tract. The importance of these proteins is underpinned by the fact that impairment of their physiological function is associated with functional dysregulation, structural remodeling, or hereditary diseases of the lung. This paper reviews the field of chloride channels and transporters in the lung and discusses chloride channels in disease processes such as viral infections including SARS-CoV- 2, pulmonary arterial hypertension, cystic fibrosis and asthma. Although chloride channels have become a hot research topic in recent years, remarkably few of them have been targeted by pharmacological agents. As such, we complement the putative pathophysiological role of chloride channels here with a summary of their therapeutic potential.

Ultrastructural Characterization of Human Bronchial Epithelial Cells during SARS-CoV-2 Infection: Morphological Comparison of Wild-Type and CFTR-Modified Cells.

SARS-CoV-2 replicates in host cell cytoplasm. People with cystic fibrosis, considered at risk of developing severe symptoms of COVID-19, instead, tend to show mild symptoms. We, thus, analyzed at the ultrastructural level the morphological effects of SARS-CoV-2 infection on wild-type (WT) and F508del (ΔF) CFTR-expressing CFBE41o- cells at early and late time points post infection. We also investigated ACE2 expression through immune-electron microscopy. At early times of infection, WT cells exhibited double-membrane vesicles, representing typical replicative structures, with granular and vesicular content, while at late time points, they contained vesicles with viral particles. ∆F cells exhibited double-membrane vesicles with an irregular shape and degenerative changes and at late time of infection, showed vesicles containing viruses lacking a regular structure and a well-organized distribution. ACE2 was expressed at the plasma membrane and present in the cytoplasm only at early times in WT, while it persisted even at late times of infection in ΔF cells. The autophagosome content also differed between the cells: in WT cells, it comprised vesicles associated with virus-containing structures, while in ΔF cells, it comprised ingested material for lysosomal digestion. Our data suggest that CFTR-modified cells infected with SARS-CoV-2 have impaired organization of normo-conformed replicative structures.

COVID-19 Lockdown Impacts Among Patients with Cystic Fibrosis: An Italian Regional Reference Centre Experience.

BACKGROUND: Coronavirus pandemic has influenced our society with social distancing and management of chronic disease such as cystic fibrosis (CF). During the Italian lockdown from March to May 2020, CF patients reduced the number of outpatient visits, limited social interactions and spent more time at home. The aim of this study is to evaluate the impact of the lockdown on body mass index (BMI) and lung function tests on CF patients. METHODS: We retrospectively reviewed clinical data about 111 CF patients followed in our Regional Cystic Fibrosis Reference Centre (Policlinico Umberto I, Rome) according to two periods: pre-lockdown (from October 2019-March 2020) and post-lockdown (from May 2020-October 2020). We collected data on nutritional (BMI and body weight) and lung function status; we chose the best values of the 'pre-lockdown' and 'post-lockdown' period for each patient. Patients were divided into 3 groups according to FEV1 value (Forced Expiratory Volume in the 1st second): group 1 (FEV1 <40%), group 2 (FEV1 40-70%), group 3 (FEV1 >70%). All patients received a telephone interview asking for the number of hours per week devoted to physical activity, number of pulmonary acute exacerbations and subjective evaluation of adherence to medical therapy, respiratory physiotherapy and diet, during the two periods. RESULTS: Comparing weight, BMI and respiratory function between pre and post lockdown periods, we noticed an increase in weight during among overall patients. Male patients improved weight, BMI, FEF 25-75% (Forced Expiratory flow between 25% and 75% of vital capacity) and Tiffenau index more than female patients. The most severely compromised patients (group 1), showed a significant loss of both weight and BMI. Instead, patients with moderate respiratory function (group 2) showed a significant increase of both weight and BMI and a slightly reduced CVF (Forced Vital capacity). We found no differences among patients with good respiratory function (group 3). Comparing each clinical sub-groups, we noticed a significative improvement of weight (p = 0.018) and BMI (p = 0.030) among patients with moderate respiratory function compared to patients with compromised respiratory function. During lockdown, patients reported less physical activity, no variation in food amount and composition, more adherence to therapy (43%) and more consistent daily respiratory physiotherapy (47.6%). CONCLUSIONS: Lockdown period had benefit among CF patients in terms of weight in particular in male patient. The greatest benefit on nutritional state was observed in patients with moderate reduction of respiratory function. In addition, we noted a stabilization and sometimes a slight improvement of lung function, instead of a continuous and steady decline that is normally observed in CF patients. These beneficial effects are slight but significative, bearing in mind the general worsening that CF patients experience annually.

TMED3 Complex Mediates ER Stress-Associated Secretion of CFTR, Pendrin, and SARS-CoV-2 Spike.

Under ER stress conditions, the ER form of transmembrane proteins can reach the plasma membrane via a Golgi-independent unconventional protein secretion (UPS) pathway. However, the targeting mechanisms of membrane proteins for UPS are unknown. Here, this study reports that TMED proteins play a critical role in the ER stress-associated UPS of transmembrane proteins. The gene silencing results reveal that TMED2, TMED3, TMED9 and TMED10 are involved in the UPS of transmembrane proteins, such as CFTR, pendrin and SARS-CoV-2 Spike. Subsequent mechanistic analyses indicate that TMED3 recognizes the ER core-glycosylated protein cargos and that the heteromeric TMED2/3/9/10 complex mediates their UPS. Co-expression of all four TMEDs improves, while each single expression reduces, the UPS and ion transport function of trafficking-deficient ΔF508-CFTR and p.H723R-pendrin, which cause cystic fibrosis and Pendred syndrome, respectively. In contrast, TMED2/3/9/10 silencing reduces SARS-CoV-2 viral release. These results provide evidence for a common role of TMED3 and related TMEDs in the ER stress-associated, Golgi-independent secretion of transmembrane proteins.