Cystic Fibrosis
Optimal Therapeutic Drug Monitoring Strategy for IV Aminoglycosides and IV Vancomycin in People with Cystic Fibrosis: A Systematic Review
Can J Hosp Pharm. 2023 Sep 1;76(4):317-323. doi: 10.4212/cjhp.3429. eCollection 2023 Fall.
ABSTRACT
BACKGROUND: Given altered pharmacokinetics in people with cystic fibrosis (pwCF), there is debate regarding optimal strategies for therapeutic drug monitoring (TDM) for aminoglycosides and vancomycin administered intravenously.
OBJECTIVES: To determine the TDM strategy for IV aminoglycosides and IV vancomycin associated with optimal clinical outcomes in pwCF.
DATA SOURCES: Several databases (MEDLINE, Embase, CINAHL, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov ) were searched from inception to November 15, 2020, with searches rerun on February 13, 2023.
STUDY SELECTION AND DATA EXTRACTION: Full articles evaluating TDM strategies and clinical outcomes in pwCF receiving IV aminoglycosides or IV vancomycin were included.
DATA SYNTHESIS: Three studies met the inclusion criteria for IV aminoglycosides, and 1 study met the inclusion criteria for IV vancomycin. Data are presented with descriptive analyses.
CONCLUSIONS: The available evidence is insufficient to determine an optimal TDM strategy for IV aminoglycoside or IV vancomycin therapy in pwCF.
PMID:37767394 | PMC:PMC10522348 | DOI:10.4212/cjhp.3429
Cystic fibrosis autoantibody signatures associate with <em>Staphylococcus aureus</em> lung infection or cystic fibrosis-related diabetes
Front Immunol. 2023 Sep 11;14:1151422. doi: 10.3389/fimmu.2023.1151422. eCollection 2023.
ABSTRACT
INTRODUCTION: While cystic fibrosis (CF) lung disease is characterized by persistent inflammation and infections and chronic inflammatory diseases are often accompanied by autoimmunity, autoimmune reactivity in CF has not been studied in depth.
METHODS: In this work we undertook an unbiased approach to explore the systemic autoantibody repertoire in CF using autoantibody microarrays.
RESULTS AND DISCUSSION: Our results show higher levels of several new autoantibodies in the blood of people with CF (PwCF) compared to control subjects. Some of these are IgA autoantibodies targeting neutrophil components or autoantigens linked to neutrophil-mediated tissue damage in CF. We also found that people with CF with higher systemic IgM autoantibody levels have lower prevalence of S. aureus infection. On the other hand, IgM autoantibody levels in S. aureus-infected PwCF correlate with lung disease severity. Diabetic PwCF have significantly higher levels of IgA autoantibodies in their circulation compared to nondiabetic PwCF and several of their IgM autoantibodies associate with worse lung disease. In contrast, in nondiabetic PwCF blood levels of IgA autoantibodies correlate with lung disease. We have also identified other autoantibodies in CF that associate with P. aeruginosa airway infection. In summary, we have identified several new autoantibodies and associations of autoantibody signatures with specific clinical features in CF.
PMID:37767091 | PMC:PMC10519797 | DOI:10.3389/fimmu.2023.1151422
Recent advances in proteomic-based diagnostics of cystic fibrosis
Expert Rev Proteomics. 2023 Sep 28:1-19. doi: 10.1080/14789450.2023.2258282. Online ahead of print.
ABSTRACT
INTRODUCTION: Cystic fibrosis (CF) is a genetic disease characterized by thick and sticky mucus accumulation, which may harm numerous internal organs. Various variables such as gene modifiers, environmental factors, age of diagnosis, and CF transmembrane conductance regulator (CFTR) gene mutations influence phenotypic disease diversity. Biomarkers that are based on genomic information may not accurately represent the underlying mechanism of the disease as well as its lethal complications. Therefore, recent advancements in mass spectrometry (MS)-based proteomics may provide deep insights into CF mechanisms and cellular functions by examining alterations in the protein expression patterns from various samples of individuals with CF.
AREAS COVERED: We present current developments in MS-based proteomics, its application, and findings in CF. In addition, the future roles of proteomics in finding diagnostic and prognostic novel biomarkers.
EXPERT OPINION: Despite significant advances in MS-based proteomics, extensive research in a large cohort for identifying and validating diagnostic, prognostic, predictive, and therapeutic biomarkers for CF disease is highly needed.
PMID:37766616 | DOI:10.1080/14789450.2023.2258282
Advancements in Chitosan-Based Nanoparticles for Pulmonary Drug Delivery
Polymers (Basel). 2023 Sep 21;15(18):3849. doi: 10.3390/polym15183849.
ABSTRACT
The evolution of respiratory diseases represents a considerable public health challenge, as they are among the leading causes of death worldwide. In this sense, in addition to the high prevalence of diseases such as asthma, chronic obstructive pulmonary disease, pneumonia, cystic fibrosis, and lung cancer, emerging respiratory diseases, particularly those caused by members of the coronavirus family, have contributed to a significant number of deaths on a global scale over the last two decades. Therefore, several studies have been conducted to optimize the efficacy of treatments against these diseases, focusing on pulmonary drug delivery using nanomedicine. Thus, the development of nanocarriers has emerged as a promising alternative to overcome the limitations of conventional therapy, by increasing drug bioavailability at the target site and reducing unwanted side effects. In this context, nanoparticles composed of chitosan (CS) show advantages over other nanocarriers because chitosan possesses intrinsic biological properties, such as anti-inflammatory, antimicrobial, and mucoadhesive capacity. Moreover, CS nanoparticles have the potential to enhance drug stability, prolong the duration of action, improve drug targeting, control drug release, optimize dissolution of poorly soluble drugs, and increase cell membrane permeability of hydrophobic drugs. These properties could optimize the performance of the drug after its pulmonary administration. Therefore, this review aims to discuss the potential of chitosan nanoparticles for pulmonary drug delivery, highlighting how their biological properties can improve the treatment of pulmonary diseases, including their synergistic action with the encapsulated drug.
PMID:37765701 | DOI:10.3390/polym15183849
Preclinical Investigation of a Lipoglycopeptide Dry Powder Inhalation Therapy for the Treatment of Pulmonary MRSA Infection
Pharmaceutics. 2023 Aug 31;15(9):2250. doi: 10.3390/pharmaceutics15092250.
ABSTRACT
The increased prevalence of pulmonary methicillin-resistant Staphylococcus aureus (MRSA) infection in patients living with cystic fibrosis (CF) is concerning due to a correlation with reduced life expectancy and lack of available treatment options. RV94 is a next generation lipoglycopeptide designed for pulmonary delivery that preclinically demonstrated high potency against MRSA in planktonic and protected colonies and improved pulmonary clearance relative to same class molecules. Here, RV94 was formulated into a dry powder for inhalation (DPI) to investigate the localized treatment of pulmonary MRSA presented in a potentially more convenient dosage form. RV94 DPI was generated using a spray-drying process with 12.5 wt% trileucine and demonstrated aerosol characteristics (2.0 μm MMAD and 73% FPF) predictive of efficient pulmonary deposition. In vivo PK from a single dose of RV94 DPI delivered by inhalation to rats yielded lung levels (127 μg/g) much greater than the MRSA minimum inhibitory concentration (0.063 μg/mL), low systemic levels (0.1 μg/mL), and a lung t1/2 equal to 3.5 days. In a rat acute pulmonary MRSA model, a single dose of RV94 DPI delivered by inhalation either up to seven days prior to or 24 h after infection resulted in a statistically significant reduction in lung MRSA titer.
PMID:37765219 | DOI:10.3390/pharmaceutics15092250
Sputum from People with Cystic Fibrosis Reduces the Killing of Methicillin-Resistant <em>Staphylococcus aureus</em> by Neutrophils and Diminishes Phagosomal Production of Reactive Oxygen Species
Pathogens. 2023 Sep 9;12(9):1148. doi: 10.3390/pathogens12091148.
ABSTRACT
Cystic fibrosis (CF) airway disease is characterized by chronic polymicrobial infections and an infiltration of neutrophils (PMNs). Staphylococcus aureus has been the most prevalent respiratory pathogen in CF. In particular, methicillin-resistant S. aureus (MRSA) represents a huge clinical burden in CF due to its association with lung disease and increased resistance to antibiotics. In CF, PMNs are unable to kill and clear MRSA. The reason for this remains largely unknown. Our study found that CF PMNs are as equally capable of killing MRSA as healthy PMNs. We show that the CF sputum, however, significantly impairs the ability of human PMNs to kill CF MRSA isolates. In the absence of CF sputum, PMNs kill MRSA via intracellular mechanisms mediated by phagocytosis, rather than extracellular mechanisms via NET formation. CF sputum does not affect the phagocytosis of MRSA via healthy or CF PMNs. Our results demonstrate that CF sputum exposure impairs phagosomal levels of reactive oxygen species (ROS) in MRSA-phagocytosing PMNs. While phagosomal co-localizations of MRSA with primary granule markers, myeloperoxidase and cathepsin D, were significantly reduced upon CF sputum exposure, that of a third azurophilic granule marker, neutrophil elastase, remained unaffected. This suggests that CF sputum does not compromise the fusion of primary granules with phagosomes but diminishes phagosomal ROS levels via another, likely more specific, mechanism. Overall, we identified the airway environment as an important factor that restricts neutrophils' oxidative microbicidal activities in CF against MRSA. These results deliver new details of the complex host-pathogen interactions present in the CF lung.
PMID:37764956 | DOI:10.3390/pathogens12091148
Chitosan-Glycolic Acid Gel Modification of Chloride Ion Transport in Mammalian Skin: An In Vitro Study
Molecules. 2023 Sep 12;28(18):6581. doi: 10.3390/molecules28186581.
ABSTRACT
Chitosan, a polyaminosaccharide with high medical and cosmetic potential, can be combined with the beneficial properties of glycolic acid to form a gel that not only moisturizes the skin, but also has a regenerative effect. Its involvement in the activation of biochemical processes may be associated with the activity of skin ion channels. Therefore, the aim of the research was to evaluate the immediate (15 s) and long-term (24 h) effect of chitosan-glycolic acid gel (CGG) on the transepithelial electric potential and the transepithelial electric resistance (R) of skin specimens tested in vitro. Stimulation during immediate and prolonged application of CGG to skin specimens resulted in a significant decrease in the measured minimal transepithelial electric potential (PDmin). The absence of any change in the R after the CGG application indicates that it does not affect the skin transmission, or cause distortion, microdamage or changes in ion permeability. However, the reduction in potential may be due to the increased transport of chloride ions, and thus water, from outside the cell into the cell interior. Increased secretion of chloride ions is achieved by stimulating the action of the CFTR (cystic fibrosis transmembrane conductance). It can be assumed that chitosan gently stimulates the secretion of chlorides, while maintaining a tendency to reduce the transport of sodium ions, without causing deformation or tissue damage.
PMID:37764357 | DOI:10.3390/molecules28186581
Development of Quinazolinone Derivatives as Modulators of Virulence Factors of <em>Pseudomonas aeruginosa</em> Cystic Fibrosis Strains
Molecules. 2023 Sep 9;28(18):6535. doi: 10.3390/molecules28186535.
ABSTRACT
Pseudomonas aeruginosa (PA), one of the ESKAPE pathogens, is an opportunistic Gram-negative bacterium responsible for nosocomial infections in humans but also for infections in patients affected by AIDS, cancer, or cystic fibrosis (CF). Treatment of PA infections in CF patients is a global healthcare problem due to the ability of PA to gain antibiotic tolerance through biofilm formation. Anti-virulence compounds represent a promising approach as adjuvant therapy, which could reduce or eliminate the pathogenicity of PA without impacting its growth. Pyocyanin is one of the virulence factors whose production is modulated by the Pseudomonas quinolone signal (PQS) through its receptor PqsR. Different PqsR modulators have been synthesized over the years, highlighting this new powerful therapeutic strategy. Based on the promising structure of quinazolin-4(3H)-one, we developed compounds 7a-d, 8a,b, 9, 10, and 11a-f able to reduce biofilm formation and the production of virulence factors (pyocyanin and pyoverdine) at 50 µM in two PA strains responsible for CF acute and chronic infections. The developed compounds did not reduce the cell viability of IB3-1 bronchial CF cells, and computational studies confirmed the potential ability of novel compounds to act as potential Pqs system modulators.
PMID:37764311 | DOI:10.3390/molecules28186535
Fibroblast Growth Factor 23 Signaling Does Not Increase Inflammation from <em>Pseudomonas aeruginosa</em> Infection in the Cystic Fibrosis Bronchial Epithelium
Medicina (Kaunas). 2023 Sep 9;59(9):1635. doi: 10.3390/medicina59091635.
ABSTRACT
Background and Objectives: Chronic inflammation due to Pseudomonas aeruginosa (PA) infection in people with cystic fibrosis (CF) remains a concerning issue in the wake of modulator therapy initiation. Given the perpetuating cycle of colonization, infection, chronic inflammation, and recurrent injury to the lung, there are increases in the risk for mortality in the CF population. We have previously shown that fibroblast growth factor (FGF) 23 can exaggerate transforming growth factor (TGF) beta-mediated bronchial inflammation in CF. Our study aims to shed light on whether FGF23 signaling also plays a role in PA infection of the CF bronchial epithelium. Materials and Methods: CF bronchial epithelial cells were pretreated with FGF23 or inhibitors for FGF receptors (FGFR) and then infected with different PA isolates. After infection, immunoblot analyses were performed on these samples to assess the levels of phosphorylated phospholipase C gamma (PLCγ), total PLCγ, phosphorylated extracellular signal-regulated kinase (ERK), and total ERK. Additionally, the expression of FGFRs and interleukins at the transcript level (RT-qPCR), as well as production of interleukin (IL)-6 and IL-8 at the protein level (ELISA) were determined. Results: Although there were decreases in isoform-specific FGFRs with increases in interleukins at the mRNA level as well as phosphorylated PLCγ and the production of IL-8 protein with PA infection, treatment with FGF23 or FGFR blockade did not alter downstream targets such as IL-6 and IL-8. Conclusions: FGF23 signaling does not seem to modulate the PA-mediated inflammatory response of the CF bronchial epithelium.
PMID:37763754 | DOI:10.3390/medicina59091635
Advances in the Cystic Fibrosis Drug Development Pipeline
Life (Basel). 2023 Aug 30;13(9):1835. doi: 10.3390/life13091835.
ABSTRACT
Cystic fibrosis is a genetic disease that results in progressive multi-organ manifestations with predominance in the respiratory and gastrointestinal systems. The significant morbidity and mortality seen in the CF population has been the driving force urging the CF research community to further advance treatments to slow disease progression and, in turn, prolong life expectancy. Enormous strides in medical advancements have translated to improvement in quality of life, symptom burden, and survival; however, there is still no cure. This review discusses the most current mainstay treatments and anticipated therapeutics in the CF drug development pipeline within the mechanisms of mucociliary clearance, anti-inflammatory and anti-infective therapies, restoration of the cystic fibrosis transmembrane conductance regulator (CFTR) protein (also known as highly effective modulator therapy (HEMT)), and genetic therapies. Ribonucleic acid (RNA) therapy, gene transfer, and gene editing are being explored in the hopes of developing a treatment and potential cure for people with CF, particularly for those not responsive to HEMT.
PMID:37763239 | DOI:10.3390/life13091835
Impaired Nitric Oxide Synthetase Activity in Primary Ciliary Dyskinesia-Data-Driven Hypothesis
J Clin Med. 2023 Sep 16;12(18):6010. doi: 10.3390/jcm12186010.
ABSTRACT
Low nasal nitric oxide (nNO) is a typical feature of Primary Ciliary Dyskinesia (PCD). nNO is part of the PCD diagnostic algorithm due to its discriminative power against other lung diseases, such as cystic fibrosis (CF). However, the underlying pathomechanisms are elusive. To better understand NO dysregulation in PCD, the L-arginine/NO (Arg/NO) pathway in patients with PCD (pwPCD) and CF (pwCF) and in healthy control (HC) subjects was investigated. In a prospective, controlled study, we measured in 24 pwPCD, 25 age-matched pwCF, and 14 HC the concentrations of the NO precursors Arg and homoarginine (hArg), the arginase metabolite ornithine (Orn), the NO inhibitor asymmetric dimethylarginine (ADMA), and the major NO metabolites (nitrate, nitrite) in sputum, plasma, and urine using validated methods. In comparison to HC, the sputum contents (in µmol/mg) of L-Arg (PCD 18.43 vs. CF 329.46 vs. HC 9.86, p < 0.001) and of ADMA (PCD 0.055 vs. CF 0.015 vs. HC 0.010, p < 0.001) were higher. In contrast, the sputum contents (in µmol/mg) of nitrate and nitrite were lower in PCD compared to HC (nitrite 4.54 vs. 9.26, p = 0.023; nitrate 12.86 vs. 40.33, p = 0.008), but higher in CF (nitrite 16.28, p < 0.001; nitrate 56.83, p = 0.002). The metabolite concentrations in urine and plasma were similar in all groups. The results of our study indicate that PCD, unlike CF, is associated with impaired NO synthesis in the lung, presumably due to mechano-chemical uncoupling.
PMID:37762950 | DOI:10.3390/jcm12186010
Dissecting Airborne Allergens
J Clin Med. 2023 Sep 8;12(18):5856. doi: 10.3390/jcm12185856.
ABSTRACT
Asthma is a heterogeneous and very complex group of diseases, and includes different clinical phenotypes depending on symptoms, progression, exacerbation patterns, or responses to treatment, among other characteristics. The allergic phenotype is the most frequent, especially in pediatric asthma. It is characterized by sensitization (the production of specific IgEs) to allergens and frequent comorbidity with rhinitis as well as atopic dermatitis. Given the complexity of allergic asthma, knowledge of it must be approached from different points of view: clinical, histological, physiological, epidemiological, biochemical, and immunological, among others. Since partial approaches do not allow for the understanding of this complexity, it is necessary to have multidimensional knowledge that helps in performing the optimal management of each case, avoiding a "blind men and elephant parable" approach. Allergens are antigens that trigger the production of specific IgE antibodies in susceptible individuals, who present symptoms that will depend on the type and intensity of the allergenic load as well as the tissue where the interaction occurs. Airborne allergens cause their effects in the respiratory tract and eyes, and can be indoor or outdoor, perennial, or seasonal. Although allergens such as mites, pollens, or animal dander are generally considered single particles, it is important to note that they contain different molecules which could trigger distinct specific IgE molecules in different patients. General practitioners, pediatricians, and other physicians typically diagnose and treat asthma based on clinical and pulmonary function data in their daily practice. This nonsystematic and nonexhaustive revision aims to update other topics, especially those focused on airborne allergens, helping the diagnostic and therapeutic processes of allergic asthma and rhinitis.
PMID:37762797 | DOI:10.3390/jcm12185856
Dynamic Hyperinflation While Exercising-A Potential Predictor of Pulmonary Deterioration in Cystic Fibrosis
J Clin Med. 2023 Sep 8;12(18):5834. doi: 10.3390/jcm12185834.
ABSTRACT
BACKGROUND: Lung function deterioration in cystic fibrosis (CF) is typically measured by a decline in the forced expiratory volume in one second (FEV1%), which is thought to be a late marker of lung disease. Dynamic hyperinflation (DH) is seen in obstructive lung diseases while exercising. Our aim was to assess whether DH could predict pulmonary deterioration in CF; a secondary measure was the peak VO2.
METHODS: A retrospective study was conducted of people with CF who performed cardiopulmonary exercise tests (CPETs) during 2012-2018. The tests were classified as those demonstrating DH non-DH. Demographic, genetic, and clinical data until 12.2022 were extracted from patient charts.
RESULTS: A total of 33 patients aged 10-61 years performed 41 valid CPETs with valid DH measurements; sixteen (39%) demonstrated DH. At the time of the CPETs, there was no difference in the FEV1% measurements between the DH and non-DH groups (median 83.5% vs. 87.6%, respectively; p = 0.174). The FEV1% trend over 4 years showed a decline in the DH group compared to the non-DH group (p = 0.009). A correlation was found between DH and the lung clearance index (LCI), as well as the FEV1% (r = 0.36 and p = 0.019 and r = -0.55 and p = 0.004, respectively). Intravenous (IV) antibiotic courses during the 4 years after the CPETs were significantly more frequent in the DH group (p = 0.046). The peak VO2 also correlated with the FEV1% and LCI (r = 0.36 and p = 0.02 and r = -0.46 and p = 0.014, respectively) as well as with the IV antibiotic courses (r = -0.46 and p = 0.014).
CONCLUSIONS: In our cohort, the DH and peak VO2 were both associated with lung function deterioration and more frequent pulmonary exacerbations. DH may serve as a marker to predict pulmonary deterioration in people with CF.
PMID:37762775 | DOI:10.3390/jcm12185834
The Anion Channel TMEM16a/Ano1 Modulates CFTR Activity, but Does Not Function as an Apical Anion Channel in Colonic Epithelium from Cystic Fibrosis Patients and Healthy Individuals
Int J Mol Sci. 2023 Sep 18;24(18):14214. doi: 10.3390/ijms241814214.
ABSTRACT
Studies in human colonic cell lines and murine intestine suggest the presence of a Ca2+-activated anion channel, presumably TMEM16a. Is there a potential for fluid secretion in patients with severe cystic fibrosis transmembrane conductance regulator (CFTR) mutations by activating this alternative pathway? Two-dimensional nondifferentiated colonoid-myofibroblast cocultures resembling transit amplifying/progenitor (TA/PE) cells, as well as differentiated monolayer (DM) cultures resembling near-surface cells, were established from both healthy controls (HLs) and patients with severe functional defects in the CFTR gene (PwCF). F508del mutant and CFTR knockout (null) mice ileal and colonic mucosa was also studied. HL TA/PE monolayers displayed a robust short-circuit current response (ΔIeq) to UTP (100 µM), forskolin (Fsk, 10 µM) and carbachol (CCH, 100 µM), while ΔIeq was much smaller in differentiated monolayers. The selective TMEM16a inhibitor Ani9 (up to 30 µM) did not alter the response to luminal UTP, significantly decreased Fsk-induced ΔIeq, and significantly increased CCH-induced ΔIeq in HL TA/PE colonoid monolayers. The PwCF TA/PE and the PwCF differentiated monolayers displayed negligible agonist-induced ΔIeq, without a significant effect of Ani9. When TMEM16a was localized in intracellular structures, a staining in the apical membrane was not detected. TMEM16a is highly expressed in human colonoid monolayers resembling transit amplifying cells of the colonic cryptal neck zone, from both HL and PwCF. While it may play a role in modulating agonist-induced CFTR-mediated anion currents, it is not localized in the apical membrane, and it has no function as an apical anion channel in cystic fibrosis (CF) and healthy human colonic epithelium.
PMID:37762516 | DOI:10.3390/ijms241814214
Reduced Sphingosine in Cystic Fibrosis Increases Susceptibility to <em>Mycobacterium abscessus</em> Infections
Int J Mol Sci. 2023 Sep 12;24(18):14004. doi: 10.3390/ijms241814004.
ABSTRACT
Cystic fibrosis (CF) is an autosomal recessive disorder caused by the deficiency of the cystic fibrosis transmembrane conductance regulator (CFTR) and often leads to pulmonary infections caused by various pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, and nontuberculous mycobacteria, particularly Mycobacterium abscessus. Unfortunately, M. abscessus infections are increasing in prevalence and are associated with the rapid deterioration of CF patients. The treatment options for M. abscessus infections are limited, requiring the urgent need to comprehend infectious pathogenesis and develop new therapeutic interventions targeting affected CF patients. Here, we show that the deficiency of CFTR reduces sphingosine levels in bronchial and alveolar epithelial cells and macrophages from CF mice and humans. Decreased sphingosine contributes to the susceptibility of CF tissues to M. abscessus infection, resulting in a higher incidence of infections in CF mice. Notably, treatment of M. abscessus with sphingosine demonstrated potent bactericidal activity against the pathogen. Most importantly, restoration of sphingosine levels in CF cells, whether human or mouse, and in the lungs of CF mice, provided protection against M. abscessus infections. Our findings demonstrate that pulmonary sphingosine levels are important in controlling M. abscessus infection. These results offer a promising therapeutic avenue for CF patients with pulmonary M. abscessus infections.
PMID:37762308 | DOI:10.3390/ijms241814004
Quantitative Evaluation of <em>CFTR</em> Gene Expression: A Comparison between Relative Quantification by Real-Time PCR and Absolute Quantification by Droplet Digital PCR
Genes (Basel). 2023 Sep 9;14(9):1781. doi: 10.3390/genes14091781.
ABSTRACT
In the precision medicine era of cystic fibrosis (CF), therapeutic interventions, by the so-called modulators, target the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The levels of targetable CFTR proteins are a main variable in the success of patient-specific therapy. In turn, the CFTR protein level depends, at least in part, on the level of CFTR mRNA. Many mechanisms can modulate the CFTR mRNA level, for example, transcriptional rate, stability of the mRNA, epigenetics, and pathogenic variants that can affect mRNA production and degradation. Independently from the causes of variable CFTR mRNA levels, their exact quantitative assessment is of great importance in CF. Methods with high analytical sensitivity, precision, and accuracy are mandatory for the quantitative evaluation aimed at the amelioration of the diagnostic, prognostic, and therapeutic aspects. This paper compares, for the first time, two CFTR gene expression quantification methods: a well-established method for the relative quantification of CFTR mRNA using a real-time PCR and an innovative method for its absolute quantification using a droplet digital PCR. No comprehensive methods for absolute CFTR quantification via droplet digital PCR have been published so far. The accurate quantification of CFTR expression at the mRNA level is a critical step for the personalized therapeutic approaches of CF.
PMID:37761921 | DOI:10.3390/genes14091781
Clinical and Genetic Characteristics of a Patient with Cystic Fibrosis with a Complex Allele [E217G;G509D] and Functional Evaluation of the CFTR Channel
Genes (Basel). 2023 Aug 28;14(9):1705. doi: 10.3390/genes14091705.
ABSTRACT
The intricate nature of complex alleles presents challenges in the classification of CFTR gene mutations, encompassing potential disease-causing, neutral, or treatment-modulating effects. Notably, the complex allele [E217G;G509D] remains absent from international databases, with its pathogenicity yet to be established. Assessing the functionality of apical membrane ion channels in intestinal epithelium employed the intestinal current measurements (ICM) method, using rectal biopsy material. The effectivity of CFTR-targeted therapy was evaluated using a model of intestinal organoids of a patient harboring the genotype F508del/[E217G;G509D]. ICM analysis revealed diminished chloride channel function. Remarkably, [E217G;G509D] presence within intestinal organoids correlated with heightened residual CFTR function. Employing CFTR modulators facilitated the restoration of the functional CFTR protein. This multifaceted study intertwines genetic investigations, functional analyses, and therapeutic interventions, shedding light on the intricate interplay of complex alleles within CFTR mutations. The results highlight the potential of targeted CFTR modulators to restore functional integrity, offering promise for advancing precision treatments in cystic fibrosis management.
PMID:37761847 | DOI:10.3390/genes14091705
Sonographic Detection of Fetal Cholelithiasis
Diagnostics (Basel). 2023 Sep 11;13(18):2900. doi: 10.3390/diagnostics13182900.
ABSTRACT
Fetal biliary lithiasis is a benign condition characterized by the presence of gallstones in the gallbladder of a developing fetus. It is typically detected incidentally during a routine obstetric echography. The incidence of this condition varies from 0.03% to 2.3%. In most cases, fetal cholelithiasis resolves spontaneously and has an excellent prognosis. However, there are certain risk factors that may contribute to its development. Maternal factors that increase the risk of fetal cholelithiasis include placental abruption, elevated estrogen levels, narcotic use, diabetes, enteral nutrition, and specific medications, such as ceftriaxone, furosemide, and prostaglandin E2. Fetal factors that can contribute to the condition include Rhesus or ABO blood group incompatibility, congenital anomalies affecting the cardiovascular, gastrointestinal, or urinary systems, twin pregnancies with the fetal demise of one twin, genetic anomalies such as trisomy 21, chromosomal aberrations, cystic fibrosis, growth restriction, oligohydramnios, hepatitis, or idiopathic causes. Usually, the gallstones spontaneously resolve before or after birth without requiring specific treatment. However, in rare instances, complications can arise, such as the formation of biliary sludge, inflammation of the gallbladder (cholecystitis), or obstruction of the bile ducts. If complications occur or if the gallstones persist after birth, further evaluation and management may be necessary. Treatment options can include medication, minimally invasive procedures, or, in severe cases, surgical removal of the gallbladder.
PMID:37761267 | DOI:10.3390/diagnostics13182900
Long-Term Efficacy of Mepolizumab at 3 Years in Patients with Severe Asthma: Comparison with Clinical Trials and Super Responders
Biomedicines. 2023 Aug 30;11(9):2424. doi: 10.3390/biomedicines11092424.
ABSTRACT
The efficacy mepolizumab in severe asthmatic patients is proven in the literature. Primarily to study the effect of mepolizumab on exacerbations, steroid dependence, and the continuation of efficacy in the long term. Secondarily to evaluate the effect of the drug on nasal polyps. Analyzing data from SANI (Severe Asthma Network Italy) clinics, we observed severe asthmatic patients treated with mepolizumab 100 mg/4 weeks, for a period of 3 years. 157 patients were observed. Exacerbations were reduced from the first year (-84.6%) and progressively to 90 and 95% in the second and third ones. Steroid-dependent patients decreased from 54% to 21% and subsequently to 11% in the second year and 6% in the third year. Patients with concomitant nasal polyps, assessed by SNOT-22, showed a 49% reduction in value from baseline to the third year. The study demonstrated the long-term efficacy of mepolizumab in a real-life setting.
PMID:37760865 | DOI:10.3390/biomedicines11092424
Advances in the Use of <em>N</em>-Acetylcysteine in Chronic Respiratory Diseases
Antioxidants (Basel). 2023 Sep 2;12(9):1713. doi: 10.3390/antiox12091713.
ABSTRACT
N-acetylcysteine (NAC) is widely used because of its mucolytic effects, taking part in the therapeutic protocols of cystic fibrosis. NAC is also administered as an antidote in acetaminophen (paracetamol) overdosing. Thanks to its wide antioxidative and anti-inflammatory effects, NAC may also be of benefit in other chronic inflammatory and fibrotizing respiratory diseases, such as chronic obstructive pulmonary disease, bronchial asthma, idiopathic lung fibrosis, or lung silicosis. In addition, NAC exerts low toxicity and rare adverse effects even in combination with other treatments, and it is cheap and easily accessible. This article brings a review of information on the mechanisms of inflammation and oxidative stress in selected chronic respiratory diseases and discusses the use of NAC in these disorders.
PMID:37760016 | DOI:10.3390/antiox12091713