Is cellular senescence involved in cystic fibrosis?

Loss of CFTR Reverses Senescence Hallmarks in SARS-CoV-2 Infected Bronchial Epithelial Cells

SARS-CoV-2 infection has been recently shown to induce cellular senescence in vivo. A senescence-like phenotype has been reported in cystic fibrosis (CF) cellular models. Since the previously published data highlighted a low impact of SARS-CoV-2 on CFTR-defective cells, here we aimed to investigate the senescence hallmarks in SARS-CoV-2 infection in the context of a loss of CFTR expression/function. We infected WT and CFTR KO 16HBE14o-cells with SARS-CoV-2 and analyzed both the p21 and Ki67 expression using immunohistochemistry and viral and p21 gene expression using real-time PCR. Prior to SARS-CoV-2 infection, CFTR KO cells displayed a higher p21 and lower Ki67 expression than WT cells. We detected lipid accumulation in CFTR KO cells, identified as lipolysosomes and residual bodies at the subcellular/ultrastructure level. After SARS-CoV-2 infection, the situation reversed, with low p21 and high Ki67 expression, as well as reduced viral gene expression in CFTR KO cells. Thus, the activation of cellular senescence pathways in CFTR-defective cells was reversed by SARS-CoV-2 infection while they were activated in CFTR WT cells. These data uncover a different response of CF and non-CF bronchial epithelial cell models to SARS-CoV-2 infection and contribute to uncovering the molecular mechanisms behind the reduced clinical impact of COVID-19 in CF patients.

Cellular senescence in chronic lung diseases from newborns to the elderly: An update literature review

The role of cellular senescence in age-related diseases has been fully recognized. In various age-related-chronic lung diseases, the function of alveolar epithelial cells (AECs) is impaired and alveolar regeneration disorders, especially in bronchopulmonary dysplasia，pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD), cancer, etc. Except for age-related-chronic lung diseases, an increasing number of studies are exploring the role of cellular senescence in developmental chronic lung diseases, which typically originate in childhood and even in the neonatal period. This review provides an overview of cellular senescence and lung diseases from newborns to the elderly, attempting to draw attention to the relationship between cellular senescence and developmental lung diseases.

Endowing Polyetheretherketone with Anti-Infection and Immunomodulatory Properties through Guanidination Carbon Dots Modification to Promote Osseointegration in Diabetes with MRSA Infection

Methicillin-resistant Staphylococcus aureus (MRSA) infection and compromised immunity are the severe complications associated with implantation surgery in diabetes mellitus. Enhancing the antibacterial and immunomodulatory properties of implants represents an effective approach to improve the osseointegration of implant in diabetes mellitus. Herein, guanidination carbon dots (GCDs) with antibacterial and immunoregulatory functions are synthesized. The GCDs demonstrate killing effect on MRSA without detectable induced resistance. Additionally, they promote the polarization of macrophages from the M1 to M2 subtype, with the inhibiting pro-inflammatory cytokines and promoting anti-inflammatory factors. Correspondingly, GCDs are immobilized onto sulfonated polyether ether ketone (SP@GCDs) using a polyvinyl butyraldehyde (PVB) coating layer through soaking-drying technique. SP@GCDs maintain stable antibacterial efficacy against MRSA for six consecutive days and retain the immunomodulatory function, while also possessing the long-term storage stability and biocompatibility of more than 6 months. Moreover, SP@GCDs significantly promote the proliferation and mineralization of osteoblasts. SP@GCDs facilitate osteogenesis through immunoregulatory. Additionally, SP@GCDs exert stable antibacterial and immune regulatory functions in implantation site of a diabetes rat, effectively promoting implant osseointegration regardless of the MRSA infection. These findings provide valuable insights into implant modification through designing nanomaterials with multifunction for enhancing osseointegration of diabetes mellitus, suggesting the promising clinical application prospects.

Integrated metabolomic and lipidomic analysis revealed the protective mechanisms of Erzhi Wan on senescent NRK cells through BRL cells

ETHNOPHARMACOLOGICAL RELEVANCE

Erzhi Wan (EZW), as a prescription of traditional Chinese medicine, has been used for tonifying the liver and kidney. Although past studies have shown that EZW has potential anti-aging effect, the mechanisms associated with cellular metabolomics and lipidomics are not fully understood.

AIM OF THE STUDY

This study aimed to evaluate the anti-aging effect of EZW and investigate the mechanisms associated with cellular metabolomics and lipidomics.

MATERIALS AND METHODS

EZW solution at dosage of 3.6 g/kg in Sprague-Dawley rats was orally administered twice a day for 7 days and serum containing EZW was then collected. NRK cell senescence model induced by D-galactose was established in vitro, and non-contact co-culture cell assay was performed between senescent NRK cells and BRL cells intervened by serum containing EZW. The anti-aging effect of EZW on NRK cells was evaluated by metabolites identification, differential metabolites screening and metabolic pathways analysis through cellular metabolomics with GC-MS and lipidomics with UHPLC-Q-Exactive Orbitrap/MS.

RESULTS

Serum containing EZW indicated a protective effect through intervening BRL cells in non-contact co-culture system with D-gal-induced senescent NRK cells. For metabolic profiles, 71 endogenous metabolites were identified, among which 24 significantly differential metabolites were screened as metabolomics potential biomarkers. For lipidic profiles, 64 lipid components were identified in NRK cell samples under positive ion mode, among which 24 potential biomarkers of lipids were screened, mainly including PC and PE. 127 lipid components were identified in NRK cell samples under negative ion mode, among which 59 potential biomarkers of lipids were screened, including FA, PC, PE, PI and PS. Metabolic pathway analysis demonstrated that the identified differential metabolites found mainly involved in amino acids metabolism, energy metabolism and phospholipid biosynthesis pathways.

CONCLUSION

Serum containing EZW exhibited protective effect on D-gal-induced senescent NRK cells through intervening BRL cells by mainly regulating amino acids metabolism, energy metabolism and phospholipid biosynthesis pathways to possess its anti-aging function, providing a theoretical basis for clinical treatment of EZW.

Cellular Senescence Contributes to the Progression of Hyperoxic Bronchopulmonary Dysplasia

Oxidative stress, inflammation, and endoplasmic reticulum (ER) stress sequentially occur in bronchopulmonary dysplasia (BPD), and all result in DNA damage. When DNA damage becomes irreparable, tumor suppressors increase, followed by apoptosis or senescence. Although cellular senescence contributes to wound healing, its persistence inhibits growth. Therefore, we hypothesized that cellular senescence contributes to BPD progression. Human autopsy lungs were obtained. Sprague-Dawley rat pups exposed to 95% oxygen between Postnatal Day 1 (P1) and P10 were used as the BPD phenotype. N-acetyl-lysyltyrosylcysteine-amide (KYC), tauroursodeoxycholic acid (TUDCA), and Foxo4 dri were administered intraperitoneally to mitigate myeloperoxidase oxidant generation, ER stress, and cellular senescence, respectively. Lungs were examined by histology, transcriptomics, and immunoblotting. Cellular senescence increased in rat and human BPD lungs, as evidenced by increased oxidative DNA damage, tumor suppressors, GL-13 stain, and inflammatory cytokines with decreased cell proliferation and lamin B expression. Cellular senescence-related transcripts in BPD rat lungs were enriched at P10 and P21. Single-cell RNA sequencing showed increased cellular senescence in several cell types, including type 2 alveolar cells. In addition, Foxo4-p53 binding increased in BPD rat lungs. Daily TUDCA or KYC, administered intraperitoneally, effectively decreased cellular senescence, improved alveolar complexity, and partially maintained the numbers of type 2 alveolar cells. Foxo4 dri administered at P4, P6, P8, and P10 led to outcomes similar to TUDCA and KYC. Our data suggest that cellular senescence plays an essential role in BPD after initial inducement by hyperoxia. Reducing myeloperoxidase toxic oxidant production, ER stress, and attenuating cellular senescence are potential therapeutic strategies for halting BPD progression.

Discovery of dysregulated circular RNAs in whole blood transcriptomes from cystic fibrosis patients - implication of a role for cellular senescence in cystic fibrosis

BACKGROUND

A largely unexplored area of research is the identification and characterization of circular RNA (circRNA) in cystic fibrosis (CF). This study is the first to identify and characterize alterations in circRNA expression in cells lacking CFTR function. The circRNA expression profiles in whole blood transcriptomes from CF patients homozygous for the pathogenetic variant F508delCFTR are compared to healthy controls.

METHODS

We developed a circRNA pipeline called circRNAFlow utilizing Nextflow. Whole blood transcriptomes from CF patients homozygous for the F508delCFTR-variant and healthy controls were utilized as input to circRNAFlow to discover dysregulated circRNA expression in CF samples compared to wild-type controls. Pathway enrichment analyzes were performed to investigate potential functions of dysregulated circRNAs in whole blood transcriptomes from CF samples compared to wild-type controls.

RESULTS

A total of 118 dysregulated circRNAs were discovered in whole blood transcriptomes from CF patients homozygous for the F508delCFTR variant compared to healthy controls. 33 circRNAs were up regulated whilst 85 circRNAs were down regulated in CF samples compared to healthy controls. The overrepresented pathways of the host genes harboring dysregulated circRNA in CF samples compared to controls include positive regulation of responses to endoplasmic reticulum stress, intracellular transport, protein serine/threonine kinase activity, phospholipid-translocating ATPase complex, ferroptosis and cellular senescence. These enriched pathways corroborate the role of dysregulated cellular senescence in CF.

CONCLUSION

This study highlights the underexplored roles of circRNAs in CF with a perspective to provide a more complete molecular characterization of CF.

Control of mitochondrial functions by Pseudomonas aeruginosa in cystic fibrosis

Cystic fibrosis (CF) is a genetic disease characterized by mutations of cystic fibrosis transmembrane conductance regulator (CFTR) gene, which lead to a dysfunctional chloride and bicarbonate channel. Abnormal mucus viscosity, persistent infections and hyperinflammation that preferentially affect the airways, referred to the pathogenesis of CF lung disease. It has largely demonstrated that Pseudomonas aeruginosa (P. aeruginosa) represents the most important pathogen that affect CF patients, leading to worsen inflammation by stimulating pro-inflammatory mediators release and tissue destruction. The conversion to mucoid phenotype and formation of biofilms, together with the increased frequency of mutations, are only few changes that characterize the P. aeruginosa's evolution during CF lung chronic infection. Recently, mitochondria received increasing attention due to their involvement in inflammatory-related diseases, including in CF. Alteration of mitochondrial homeostasis is sufficient to stimulate immune response. Exogenous or endogenous stimuli that perturb mitochondrial activity are used by cells, which, through the mitochondrial stress, potentiate immunity programs. Studies show the relationship between mitochondria and CF, supporting the idea that mitochondrial dysfunction endorses the exacerbation of inflammatory responses in CF lung. In particular, evidences suggest that mitochondria in CF airway cells are more susceptible to P. aeruginosa infection, with consequent detrimental effects that lead to amplify the inflammatory signals. This review discusses the evolution of P. aeruginosa in relationship with the pathogenesis of CF, a fundamental step to establish chronic infection in CF lung disease. Specifically, we focus on the role of P. aeruginosa in the exacerbation of inflammatory response, by triggering mitochondria in CF.

Toward a Broader Understanding of Cystic Fibrosis Epidemiology and Its Impact on Clinical Manifestations

The incidence of cystic fibrosis remains constant in North America and Western Europe is 1 in 3500 live births, but survival and quality of life have improved. The cystic fibrosis population has shifted toward the adult age range with a concomitant shift in the spectrum of complications. Survival increased because of aggressive symptomatic therapy, earlier diagnosis by newborn screening, and the introduction of modulators of the cystic fibrosis transmembrane conductance regulator, so that predicted median survival age is now about 50 years. In the United States, members of low socioeconomic status populations or members of racial or ethnic minorities have benefitted less from these advances.

CFTR Modulators Restore Acidification of Autophago-Lysosomes and Bacterial Clearance in Cystic Fibrosis Macrophages

Cystic fibrosis (CF) human and mouse macrophages are defective in their ability to clear bacteria such as Burkholderia cenocepacia. The autophagy process in CF (F508del) macrophages is halted, and the underlying mechanism remains unclear. Furthermore, the role of CFTR in maintaining the acidification of endosomal and lysosomal compartments in CF cells has been a subject of debate. Using 3D reconstruction of z-stack confocal images, we show that CFTR is recruited to LC3-labeled autophagosomes harboring B. cenocepacia. Using several complementary approaches, we report that CF macrophages display defective lysosomal acidification and degradative function for cargos destined to autophagosomes, whereas non-autophagosomal cargos are effectively degraded within acidic compartments. Notably, treatment of CF macrophages with CFTR modulators (tezacaftor/ivacaftor) improved the autophagy flux, lysosomal acidification and function, and bacterial clearance. In addition, CFTR modulators improved CFTR function as demonstrated by patch-clamp. In conclusion, CFTR regulates the acidification of a specific subset of lysosomes that specifically fuse with autophagosomes. Therefore, our study describes a new biological location and function for CFTR in autophago-lysosomes and clarifies the long-standing discrepancies in the field.

Inflammaging and Cannabinoids

Aging is a complex phenomenon associated with a wide spectrum of physical and physiological changes affecting every part of all metazoans, if they escape death prior to reaching maturity. Critical to survival, the immune system evolved as the principal component of response to injury and defense against pathogen invasions. Because how significantly immune system affects and is affected by aging, several neologisms now appear to encapsulate these reciprocal relationships, such as Immunosenescence. The central part of Immunosenescence is Inflammaging -a sustained, low-grade, sterile inflammation occurring after reaching reproductive prime. Once initiated, the impact of Inflammaging and its adverse effects determine the direction and magnitudes of further Inflammaging. In this article, we review the nature of this vicious cycle, we will propose that phytocannabinoids as immune regulators may possess the potential as effective adjunctive therapies to slow and, in certain cases, reverse the pathologic senescence to permit a more healthy aging.

Cystic fibrosis improves COVID-19 survival and provides clues for treatment of SARS-CoV-2

Systemic pools of ATP are elevated in individuals homozygous for cystic fibrosis (CF) as evidenced by elevated blood and plasma ATP levels. This elevated ATP level seems to provide benefit in the presence of advanced solid tumors (Abraham et al., Nature Medicine 2(5):593-596, 1996). We published in this journal a paper showing that IV ATP can elevate the depleted ATP pools of advanced cancer patients up to levels found in CF patients with subsequent clinical, biochemical, and quality of life (QOL) improvements (Rapaport et al., Purinergic Signalling 11(2): 251-262, 2015). We hypothesize that the elevated ATP levels seen in CF patients may be benefiting CF patients in another way: by improving their survival after contracting COVID-19. We discuss here the reasoning behind this hypothesis and suggest how these findings might be applied clinically in the general population.

Enhancing Cystic Fibrosis Immune Regulation

In cystic fibrosis (CF), sustained infection and exuberant inflammation results in debilitating and often fatal lung disease. Advancement in CF therapeutics has provided successful treatment regimens for a variety of clinical consequences in CF; however effective means to treat the pulmonary infection and inflammation continues to be problematic. Even with the successful development of small molecule cystic fibrosis transmembrane conductance regulator (CFTR) correctors and potentiators, there is only a modest effect on established infection and inflammation in CF patients. In the pursuit of therapeutics to treat inflammation, the conundrum to address is how to overcome the inflammatory response without jeopardizing the required immunity to manage pathogens and prevent infection. The key therapeutic would have the capacity to dull the inflammatory response, while sustaining the ability to manage infections. Advances in cell-based therapy have opened up the avenue for dynamic and versatile immune interventions that may support this requirement. Cell based therapy has the capacity to augment the patient’s own ability to manage their inflammatory status while at the same time sustaining anti-pathogen immunity. The studies highlighted in this manuscript outline the potential use of cell-based therapy for CF. The data demonstrate that 1) total bone marrow aspirates containing Cftr sufficient hematopoietic and mesenchymal stem cells (hMSCs) provide Cftr deficient mice >50% improvement in survival and improved management of infection and inflammation; 2) myeloid cells can provide sufficient Cftr to provide pre-clinical anti-inflammatory and antimicrobial benefit; 3) hMSCs provide significant improvement in survival and management of infection and inflammation in CF; 4) the combined interaction between macrophages and hMSCs can potentially enhance anti-inflammatory and antimicrobial support through manipulating PPARγ. These data support the development of optimized cell-based therapeutics to enhance CF patient’s own immune repertoire and capacity to maintain the balance between inflammation and pathogen management.

Donor-defined mesenchymal stem cell antimicrobial potency against nontuberculous mycobacterium

Chronic nontuberculous mycobacterial infections with Mycobacterium avium and Mycobacterium intracellulare complicate bronchiectasis, chronic obstructive airway disease, and the health of aging individuals. These insidious intracellular pathogens cause considerable morbidity and eventual mortality in individuals colonized with these bacteria. Current treatment regimens with antibiotic macrolides are both toxic and often inefficient at providing infection resolution. In this article, we demonstrate that human marrow‐derived mesenchymal stem cells are antimicrobial and anti‐inflammatory in vitro and in the context of an in vivo sustained infection of either M. avium and/or M. intracellulare.

Cystic Fibrosis Lung Disease in the Aging Population

The demographics of the population with cystic fibrosis (CF) is continuously changing, with nowadays adults outnumbering children and a median predicted survival of over 40 years. This leads to the challenge of treating an aging CF population, while previous research has largely focused on pediatric and adolescent patients. Chronic inflammation is not only a hallmark of CF lung disease, but also of the aging process. However, very little is known about the effects of an accelerated aging pathology in CF lungs. Several chronic lung disease pathologies show signs of chronic inflammation with accelerated aging, also termed “inflammaging”; the most notable being chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). In these disease entities, accelerated aging has been implicated in the pathogenesis via interference with tissue repair mechanisms, alterations of the immune system leading to impaired defense against pulmonary infections and induction of a chronic pro-inflammatory state. In addition, CF lungs have been shown to exhibit increased expression of senescence markers. Sustained airway inflammation also leads to the degradation and increased turnover of cystic fibrosis transmembrane regulator (CFTR). This further reduces CFTR function and may prevent the novel CFTR modulator therapies from developing their full efficacy. Therefore, novel therapies targeting aging processes in CF lungs could be promising. This review summarizes the current research on CF in an aging population focusing on accelerated aging in the context of chronic airway inflammation and therapy implications.

Cellular and molecular features of senescence in acute lung injury

A wide range of insults can trigger acute injury in the lungs, which eventually may lead to respiratory failure and death of patients. Current treatment relies mainly on supportive measures and mechanical ventilation. Even so, survivors frequently develop important sequels that compromise quality of life. In the search for new approaches to prevent and treat acute lung injury, many investigations have focused on molecular and cellular pathways which could exert a pathogenic role in this disease. Herein, we review recent findings in the literature suggesting that cellular senescence could be involved in lung injury and discuss the potential use of senotherapies to prevent disease progression.

Urinary Exosomes of Patients with Cystic Fibrosis Unravel CFTR-Related Renal Disease

Background: The prevalence of chronic kidney disease is increased in patients with cystic fibrosis (CF). The study of urinary exosomal proteins might provide insight into the pathophysiology of CF kidney disease. Methods: Urine samples were collected from 19 CF patients (among those 7 were treated by cystic fibrosis transmembrane conductance regulator (CFTR) modulators), and 8 healthy subjects. Urine exosomal protein content was determined by high resolution mass spectrometry. Results: A heatmap of the differentially expressed proteins in urinary exosomes showed a clear separation between control and CF patients. Seventeen proteins were upregulated in CF patients (including epidermal growth factor receptor (EGFR); proteasome subunit beta type-6, transglutaminases, caspase 14) and 118 were downregulated (including glutathione S-transferases, superoxide dismutase, klotho, endosomal sorting complex required for transport, and matrisome proteins). Gene set enrichment analysis revealed 20 gene sets upregulated and 74 downregulated. Treatment with CFTR modulators yielded no significant modification of the proteomic content. These results highlight that CF kidney cells adapt to the CFTR defect by upregulating proteasome activity and that autophagy and endosomal targeting are impaired. Increased expression of EGFR and decreased expression of klotho and matrisome might play a central role in this CF kidney signature by inducing oxidation, inflammation, accelerated senescence, and abnormal tissue repair. Conclusions: Our study unravels novel insights into consequences of CFTR dysfunction in the urinary tract, some of which may have clinical and therapeutic implications.

Exploring the Relevance of Senotherapeutics for the Current SARS-CoV-2 Emergency and Similar Future Global Health Threats

The higher death rate caused by COVID-19 in older people, especially those with comorbidities, is a challenge for biomedical aging research. Here we explore the idea that an exacerbated inflammatory response, in particular that mediated by IL-6, may drive the deleterious consequences of the infection. Data shows that other RNA viruses, such as influenza virus, can display enhanced replication efficiency in senescent cells, suggesting that the accumulation of senescent cells with aging and age-related diseases may play a role in this phenomenon. However, at present, we are completely unaware of the response to SARS-CoV and SARS-COV-2 occurring in senescent cells. We deem that this is a priority area of research because it could lead to the development of several therapeutic strategies based on senotherapeutics or prevent unsuccessful attempts. Two of these senotherapeutics, azithromycin and ruxolitinib, are currently undergoing testing for their efficacy in treating COVID-19. The potential of these strategies is not only for ameliorating the consequences of the current emergence of SARS-CoV-2, but also for the future emergence of new viruses or mutated ones for which we are completely unprepared and for which no vaccines are available.

Role of p53 in the Regulation of Cellular Senescence

The p53 transcription factor plays a critical role in cellular responses to stress. Its activation in response to DNA damage leads to cell growth arrest, allowing for DNA repair, or directs cellular senescence or apoptosis, thereby maintaining genome integrity. Senescence is a permanent cell-cycle arrest that has a crucial role in aging, and it also represents a robust physiological antitumor response, which counteracts oncogenic insults. In addition, senescent cells can also negatively impact the surrounding tissue microenvironment and the neighboring cells by secreting pro-inflammatory cytokines, ultimately triggering tissue dysfunction and/or unfavorable outcomes. This review focuses on the characteristics of senescence and on the recent advances in the contribution of p53 to cellular senescence. Moreover, we also discuss the p53-mediated regulation of several pathophysiological microenvironments that could be associated with senescence and its development.

Reduced expression of the Ion channel CFTR contributes to airspace enlargement as a consequence of aging and in response to cigarette smoke in mice

Chronic Obstructive Pulmonary Disease (COPD) is a complex disease resulting in respiratory failure and represents the third leading cause of global death. The two classical phenotypes of COPD are chronic bronchitis and emphysema. Owing to similarities between chronic bronchitis and the autosomal-recessive disease Cystic Fibrosis (CF), a significant body of research addresses the hypothesis that dysfunctional CF Transmembrane Conductance Regulator (CFTR) is implicated in the pathogenesis of COPD. Much less attention has been given to emphysema in this context, despite similarities between the two diseases. These include early-onset cellular senescence, similar comorbidities, and the finding that CF patients develop emphysema as they age. To determine a potential role for CFTR dysfunction in the development of emphysema, Cftr^+/+ (Wild-type; WT), Cftr^+/− (heterozygous), and Cftr^−/− (knock-out; KO) mice were aged or exposed to cigarette smoke and analyzed for airspace enlargement. Aged knockout mice demonstrated increased alveolar size compared to age-matched wild-type and heterozygous mice. Furthermore, both heterozygous and knockout mice developed enlarged alveoli compared to their wild-type counterparts following chronic smoke exposure. Taken into consideration with previous findings that cigarette smoke leads to reduced CFTR function, our findings suggest that decreased CFTR expression sensitizes the lung to the effects of cigarette smoke. These findings may caution normally asymptomatic CF carriers against exposure to cigarette smoke; as well as highlight emphysema as a future challenge for CF patients as they continue to live longer. More broadly, our data, along with clinical findings, may implicate CFTR dysfunction in a pathology resembling accelerated aging.

Progression of Cystic Fibrosis Lung Disease from Childhood to Adulthood: Neutrophils, Neutrophil Extracellular Trap (NET) Formation, and NET Degradation

Genetic defects in cystic fibrosis (CF) transmembrane conductance regulator (CFTR) gene cause CF. Infants with CFTR mutations show a peribronchial neutrophil infiltration prior to the establishment of infection in their lung. The inflammatory response progressively increases in children that include both upper and lower airways. Infectious and inflammatory response leads to an increase in mucus viscosity and mucus plugging of small and medium-size bronchioles. Eventually, neutrophils chronically infiltrate the airways with biofilm or chronic bacterial infection. Perpetual infection and airway inflammation destroy the lungs, which leads to increased morbidity and eventual mortality in most of the patients with CF. Studies have now established that neutrophil cytotoxins, extracellular DNA, and neutrophil extracellular traps (NETs) are associated with increased mucus clogging and lung injury in CF. In addition to opportunistic pathogens, various aspects of the CF airway milieux (e.g., airway pH, salt concentration, and neutrophil phenotypes) influence the NETotic capacity of neutrophils. CF airway milieu may promote the survival of neutrophils and eventual pro-inflammatory aberrant NETosis, rather than the anti-inflammatory apoptotic death in these cells. Degrading NETs helps to manage CF airway disease; since DNAse treatment release cytotoxins from the NETs, further improvements are needed to degrade NETs with maximal positive effects. Neutrophil-T cell interactions may be important in regulating viral infection-mediated pulmonary exacerbations in patients with bacterial infections. Therefore, clarifying the role of neutrophils and NETs in CF lung disease and identifying therapies that preserve the positive effects of neutrophils, while reducing the detrimental effects of NETs and cytotoxic components, are essential in achieving innovative therapeutic advances.