Cystic Fibrosis
Longitudinal effects of elexacaftor/tezacaftor/ivacaftor on the oropharyngeal metagenome in adolescents with cystic fibrosis
J Cyst Fibros. 2024 Oct 14:S1569-1993(24)01794-6. doi: 10.1016/j.jcf.2024.10.001. Online ahead of print.
ABSTRACT
BACKGROUND: Triple modulator therapy elexacaftor/tezacaftor/ivacaftor (ETI) improves lung function and impacts upon the respiratory microbiome in people with Cystic fibrosis (pwCF) with advanced lung disease. However, adolescents with cystic fibrosis (CF) are less colonized with bacterial pathogens than adult pwCF but their microbiota already differs from healthy individuals. The aim of this study was to longitudinally analyze the impact of ETI on the respiratory metagenome in adolescents with predominantly mild CF lung disease.
METHODS: In this prospective observational study, we included pwCF aged 12-20 years with at least one F508del mutation, who collected oropharyngeal swabs before and after initiation of ETI therapy twice per week to biweekly over three months. We performed whole metagenome shotgun sequencing, followed by host DNA filtering and taxonomic profiling. We used linear and additive mixed effects models adjusted for known confounders and corrected for multiple testing to study longitudinal development of the microbiome. We analyzed bacterial diversity, abundance, and strain-level phylogeny.
RESULTS: We analyzed the metagenomic data of 297 swabs of 20 pwCF. Microbiome composition changed after initiation of ETI therapy. We observed a slight diversification of the microbiome over time (Inv Simpson, Coef 0.085, 95 %CI 0.003, 0.17, p = 0.04). Strain-level analysis and clustering showed that strain retention of the most frequent bacterial species is predominant even during ETI therapy.
CONCLUSIONS: During three months of ETI therapy, commensal bacteria increased, which may help to prevent overgrowth of bacterial pathogens.
PMID:39406574 | DOI:10.1016/j.jcf.2024.10.001
Chinese expert consensus on the etiological diagnosis of adult bronchiectasis
Zhonghua Jie He He Hu Xi Za Zhi. 2024 Oct 12;47(10):921-932. doi: 10.3760/cma.j.cn112147-20240606-00315.
ABSTRACT
Bronchiectasis is a highly heterogeneous chronic airway disease for which accurate etiological diagnosis is crucial for effective management. A group of experts from the China Bronchiectasis Alliance and the Infection Assembly of the Chinese Thoracic Society conducted a comprehensive review of recent research into the etiology of bronchiectasis. Using the widely accepted Delphi methodology, the experts reached a consensus on the etiological diagnosis of bronchiectasis through multiple rounds of discussion and revision. The consensus is divided into four sections: the definition and classification of the etiology of bronchiectasis, the etiological diagnostic procedures for bronchiectasis, the treatable causes of bronchiectasis, and other causes of bronchiectasis. The ultimate goal of this consensus is to improve the diagnostic accuracy and optimize the management of bronchiectasis in China. The main recommendations of Section 1 focused on chest thin-section computed tomography (CT) for the diagnosis of bronchiectasis and the etiological classification. The main recommendations of Section 2 focused on the medical history collection for bronchiectasis and the etiological diagnostic protocol for bronchiectasis. The main recommendations of Section 3 focused on the recommendations of the diagnosis of bronchiectasis secondary to COPD, the diagnosis of bronchiectasis due to asthma, diffuse pan-bronchiolitis, allergic bronchopulmonary aspergillosis, connective tissue disease (CTD)-related bronchiectasis or gastroesophageal reflux disease (GERD)-related bronchiectasis. The main recommendations of Section 4 focused on suspected primary ciliary dyskinesia (PCD)-associated bronchiectasis, cystic fibrosis and the diagnosis of congenital airway malformations.
PMID:39406539 | DOI:10.3760/cma.j.cn112147-20240606-00315
Nontuberculous Mycobacterial Pulmonary Disease: Patients, Principles, and Prospects
Clin Infect Dis. 2024 Oct 15;79(4):e27-e47. doi: 10.1093/cid/ciae421.
ABSTRACT
Nontuberculous mycobacterial pulmonary disease (NTM-PD) is increasing in incidence globally and challenging to manage. The 2020 multisociety treatment guideline and the 2022 consensus recommendations provide comprehensive evidence-based guides to manage pulmonary diseases caused by the most common NTM. However, with >190 different NTM species that may require different multidrug regimens for treatment, the breadth and complexity of NTM-PD remain daunting for both patients and clinicians. In this narrative review, we aim to distill this broad, complex field into principles applicable to most NTM species and highlight important nuances, specifically elaborating on the presentation, diagnosis, principles of patient-centered care, principles of pathogen-directed therapy, and prospects of NTM-PD.
PMID:39405483 | DOI:10.1093/cid/ciae421
A Global Experience of Donation after Circulatory Death for Pediatric Lung Transplantation
Ann Am Thorac Soc. 2024 Oct 15. doi: 10.1513/AnnalsATS.202405-546OC. Online ahead of print.
ABSTRACT
OBJECTIVE: Donation after circulatory death (DCD) lung transplantation has increased, but there is limited data in children. We sought to characterize the international experience of pediatric DCD lung transplant (LT) in comparison to donation after brain death (DBD) to address extreme donor organ shortages in children needing LT.
METHODS: Using the International Society for Heart and Lung Transplantation (ISHLT) Thoracic Organ Transplant Registry, 1453 children (<18yo) LT recipients from January 2004 to June 2018 were identified: 34 (3%) were DCD and 1419 (97%) were DBD recipients. Post-transplant outcomes were compared between groups. Propensity score method was used to derive matched cohorts and were compared between groups.
RESULTS: DCD and DBD recipients were of similar age, with cystic fibrosis being the most frequent indication for LT in both groups (64.5% vs. 57.5%, respectively). Kaplan-Meier analysis demonstrated similar survival between DCD and DBD cohorts, whereas propensity score-matched recipients also identified similar post-transplant survival in both groups (P=0.098). Secondary analysis found that DCD LT recipients had a longer post-transplant length of hospital stay (unmatched cohorts: 36.5d vs. 20d, p=0.022; matched cohort: 26d vs. 19d, p=0.016), and shorter time to acute cellular rejection (ACR) (unmatched cohorts: 248d vs. 560d, p=0.039; matched cohorts: 248d vs. 1650d,p=0.059).
CONCLUSIONS: Due to DCD being a key contributor to the increasing number of lung transplants being performed worldwide, the results of this analysis support this organ donation approach in children requiring LT, which would increase access to donor organs. The identification of a potential shorter time to ACR needs further exploration as more DCD pediatric LTs are performed.
PMID:39405100 | DOI:10.1513/AnnalsATS.202405-546OC
Hemophagocytic Lymphohistiocytosis/Macrophage Activation Syndrome in pediatric Inflammatory Bowel Disease: clinical characteristics and outcomes
Eur J Pediatr. 2024 Oct 15. doi: 10.1007/s00431-024-05772-4. Online ahead of print.
ABSTRACT
Hemophagocytic Lymphohistiocytosis (HLH)/Macrophage Activation Syndrome (MAS) in children with inflammatory bowel disease (IBD) has been reported only anecdotally. This study aimed at describing the clinical features and outcomes of children diagnosed with both IBD and HLH/MAS. Data on IBD and HLH/MAS characteristics, biochemical, microbiological and genetic assessments, treatments, and outcomes were collected from the Italian Pediatric IBD Registry and presented using descriptive statistics. Out of 4643 patients with IBD, 18 (0.4%) were diagnosed with HLH/MAS, including 12 with ulcerative colitis and 6 with Crohn disease. Among the 18 patients, 7 (39%) had early-onset IBD, but the median age at HLH/MAS diagnosis was 14.0 years (IQR 11.9-16.0). Half of the patients had active IBD at HLH/MAS diagnosis, 11 (61%) patients were on thiopurines, and 6 (33%) were on anti-TNF biologics. An infectious trigger was identified in 15 (83%) patients. One (5%) patients was diagnosed with XIAP deficiency. All patients discontinued thiopurines and 5 (83.3%) discontinued anti-TNF biologics; 16 (80%) patients received steroids for HLH/MAS. Three (17%) patients had a relapse of HLH/MAS. No patient developed lymphoma or died during a median follow-up of 2.7 years (IQR 0.8-4.4). Conclusions: HLH/MAS mainly affects children with early-onset IBD but primarily develops during adolescence, following an infection while on immunosuppressant treatment. Although the prognosis is generally favorable, it is crucial to investigate an underlying immune deficiency.
PMID:39404873 | DOI:10.1007/s00431-024-05772-4
Characterization of Fabry disease-associated lyso-Gb<sub>3</sub> on mouse colonic ion transport and motility
Am J Physiol Gastrointest Liver Physiol. 2024 Oct 15. doi: 10.1152/ajpgi.00220.2024. Online ahead of print.
ABSTRACT
Fabry disease (FD) is a rare X-linked lysosomal storage disorder caused by a deficiency in α-galactosidase A leading to the accumulation of globotriaosylceramide (Gb3) and subsequent increase in globotriaosylsphingosine (lyso-Gb3) in different cells and organs, including the gastrointestinal (GI) tract. GI symptoms represent some of the earliest manifestations of FD and significantly impact quality of life. The origin of these symptoms is complex, and the exact mechanisms remain poorly understood. Here, we sought to determine whether lyso-Gb3 contributes to the pathophysiology of GI symptoms associated with FD by examining its effects on mouse colonic ion transport and motility ex vivo using Ussing chambers and organ baths respectively. Lyso-Gb3 significantly increased colonic baseline short-circuit current (ISC). This increase in ISC was insensitive to inhibition of the cystic fibrosis transmembrane conductance regulator and Na-K-Cl cotransporter 1 suggesting that the increase in ISC is Cl- ion independent. This response was also insensitive to inhibition with the neurotoxin, tetrodotoxin. Additionally, pretreatment with lyso-Gb3 did not significantly influence subsequent responses to either veratridine or capsaicin implying that the response to lyso-Gb3 does not involve the enteric nervous system. In terms of colonic motility, lyso-Gb3 did not significantly influence colonic tone, spontaneous contractility or cholinergic-induced contractions. These data suggest that lyso-Gb3, significantly influences ion transport in mouse colon, but that accumulation of Gb3 may be a pre-requisite for the more pronounced disturbances in GI physiology characteristic of FD.
PMID:39404773 | DOI:10.1152/ajpgi.00220.2024
Radiology of bronchiectasis
Radiologie (Heidelb). 2024 Oct 15. doi: 10.1007/s00117-024-01375-0. Online ahead of print.
ABSTRACT
Bronchiectasis is an irreversible bronchial dilatation. It is chronically progressive through a vicious circle of secretion retention, infection, inflammation and structural damage. The underlying causes are diverse and the severity of the disease is variable, which makes both the diagnostics and treatment challenging. Computed tomography (CT) is the gold standard in the diagnosis of bronchiectasis and can be helpful in clarifying the etiology. The type of bronchiectasis, the distribution of the bronchiectasis within the lungs and associated findings are particularly relevant. Imaging is also important in monitoring the progression of bronchiectasis. In the usual report of the findings this is carried out visually and descriptively, while semiquantitative scores and computer-aided quantitative analysis of the respiratory tract enable a more precise assessment and are used in particular for clinical studies.
PMID:39404768 | DOI:10.1007/s00117-024-01375-0
Association between hospital type and length of stay and readmissions for young adults with complex chronic diseases
J Hosp Med. 2024 Oct 15. doi: 10.1002/jhm.13524. Online ahead of print.
ABSTRACT
BACKGROUND: There is a paucity of information around whether hospital length of stay and readmission rates differ based upon hospital type for adolescents and young adults (AYA) with complex chronic diseases (CCDs).
OBJECTIVE: To measure the association between hospital type and readmission rates and index admission LOS among AYA with CCDs.
METHODS: We performed a retrospective cross-sectional study of 2017 Healthcare Cost and Utilization Project State Inpatient Databases, including patients 12-25 years old with cystic fibrosis (CF), sickle cell disease (SCD), spina bifida (SB), inflammatory bowel disease (IBD), and diabetes mellitus (DM). Index hospitalizations were categorized by hospital type (pediatric hospitals [PHs], adult hospitals with pediatric services [AHPSs], and adult hospitals without pediatric services [AHs]), CCD, and age group. We compared case-mix adjusted 30-day readmission rates and differences in index admission LOS between hospital types.
RESULTS: Adult hospitals without pediatric services exhibited higher readmission rates (25.4%) than AHPS (22.9%) and PH (15.1%). Compared to patients with CF admitted to AH, lower readmission rates were associated with longer LOS at both AHPS (relative ratio [RR]: 1.25, 95% confidence interval [CI]: 1.02-1.55) and PH (RR: 1.59, 95% CI: 1.28-1.97). Patients with DM admitted to AHPS (odds ratio [OR]: 0.75, 95% CI: 0.62-0.91) and PH (OR: 0.47, 95% CI: 0.31-0.71) also demonstrated lower readmission rates than those admitted to AH.
CONCLUSIONS: For AYA with CCD, hospital type is associated with differences in readmission rates and LOS. Lower readmission rates at hospitals with pediatric services compared to adult hospitals without pediatric services suggest hospital type has a significant impact on outcomes.
PMID:39404149 | DOI:10.1002/jhm.13524
Concordance of MASLD and NAFLD nomenclature in youth participating in the TARGET-NASH real-world cohort
Hepatol Commun. 2024 Oct 10;8(11):e0546. doi: 10.1097/HC9.0000000000000546. eCollection 2024 Nov 1.
NO ABSTRACT
PMID:39401124 | PMC:PMC11469899 | DOI:10.1097/HC9.0000000000000546
Genetic diagnosis and outcomes of intracytoplasmic sperm injection in South Chinese patients with congenital bilateral aplasia of the vas deferens
Basic Clin Androl. 2024 Oct 15;34(1):17. doi: 10.1186/s12610-024-00233-2.
ABSTRACT
BACKGROUND: Obstructive azoospermia commonly is caused by CBAVD(Congenital Bilateral Aplasia of the Vas Deferens), mainly due to the cystic fibrosis transmembrane conductance regulator (CFTR) and adhesion G protein-coupled receptor G2(ADGRG2) mutations. The genetic landscape for Chinese CBAVD patients is unclear, leading to debates over genetic screening, counseling, and assisted reproduction strategies. This study investigates the prevalence of CFTR and ADGRG2 mutations in a southern Chinese cohort of CBAVD patients and evaluates the impact of CFTR mutations on intracytoplasmic sperm injection (ICSI) outcomes.
RESULTS: CFTR mutations were identified in 71.4% (30/42) of CBAVD patients, with a total of 36 CFTR mutation sites across 13 types identified, including two novel mutations. A novel ADGRG2 mutation was also detected. Betweenthe CFTR mutation-CBAVD group and the non-CBAVD OA group, a significant difference was observed only in the 2 Pronuclei(2PN) rate (79.5% vs 86.2%, P = 0.0065), while fertilization rates, pregnancy rates, miscarriage rates, and live birth rates showed no significant differences. Between the CFTR mutation-CBAVD group and the CBAVD group without CFTR mutation, there were no significant differences in fertilization rates, 2PN rates, pregnancy rates, miscarriage rates, or live birth rates.
CONCLUSION: Chinese CBAVD patients primarily exhibit mutations in the CFTR and ADGRG2 genes. Therefore, targeted gene testing for CFTR and ADGRG2 is more suitable compared to WES for CBAVD patients. Considering that the genetic factors of approximately 30% of CBAVD patients remain unknown, it is recommended to perform massive parallel sequencing for patients who test negative for CFTR and ADGRG2 gene screening. Despite these genetic factors, ICSI outcomes were not adversely affected, except for the 2PN rate. However, genetic counseling remains crucial for Chinese CBAVD patients before undergoing assisted reproduction.
PMID:39402445 | DOI:10.1186/s12610-024-00233-2
Corrigendum: Inhibitory effects of calcium channel blockers nisoldipine and nimodipine on ivacaftor metabolism and their underlying mechanism
Front Pharmacol. 2024 Sep 27;15:1495855. doi: 10.3389/fphar.2024.1495855. eCollection 2024.
ABSTRACT
[This corrects the article DOI: 10.3389/fphar.2024.1403649.].
PMID:39399470 | PMC:PMC11466882 | DOI:10.3389/fphar.2024.1495855
Arsenic exposure is associated with elevated sweat chloride concentration and airflow obstruction among adults in Bangladesh: a cross sectional study
medRxiv [Preprint]. 2024 Sep 26:2024.09.25.24314390. doi: 10.1101/2024.09.25.24314390.
ABSTRACT
Arsenic is associated with lung disease and experimental models suggest that arsenic-induced degradation of the chloride channel CFTR (cystic fibrosis transmembrane conductance regulator) is a mechanism of arsenic toxicity. We examined associations between arsenic exposure, sweat chloride concentration (measure of CFTR function), and pulmonary function among 285 adults in Bangladesh. Participants with sweat chloride ≥ 60 mmol/L had higher arsenic exposures than those with sweat chloride < 60 mmol/L (water: median 77.5 µg/L versus 34.0 µg/L, p = 0.025; toenails: median 4.8 µg/g versus 3.7 µg/g, p = 0.024). In linear regression models, a one-unit µg/g increment in toenail arsenic was associated with a 0.59 mmol/L higher sweat chloride concentration, p < 0.001. We found that toenail arsenic concentration was associated with increased odds of airway obstruction (OR: 1.97, 95%: 1.06, 3.67, p = 0.03); however, sweat chloride concentration did not mediate this association. Our findings suggest that sweat chloride concentration may be a novel biomarker for arsenic exposure and also that arsenic likely acts on the lung through mechanisms other than CFTR dysfunction.
PMID:39399016 | PMC:PMC11469388 | DOI:10.1101/2024.09.25.24314390
DNA-PKcs inhibition improves sequential gene insertion of the full-length <em>CFTR</em> cDNA in airway stem cells
Mol Ther Nucleic Acids. 2024 Sep 16;35(4):102339. doi: 10.1016/j.omtn.2024.102339. eCollection 2024 Dec 10.
ABSTRACT
Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Although many people with CF (pwCF) are treated using CFTR modulators, some are non-responsive due to their genotype or other uncharacterized reasons. Autologous airway stem cell therapies, in which the CFTR cDNA has been replaced, may enable a durable therapy for all pwCF. Previously, CRISPR-Cas9 with two AAVs was used to sequentially insert two-halves of the CFTR cDNA and an enrichment cassette into the CFTR locus. However, the editing efficiency was <10% and required enrichment to restore CFTR function. Further improvement in gene insertion may enhance cell therapy production. To improve CFTR cDNA insertion in human airway basal stem cells (ABCs), we evaluated the use of the small molecules AZD7648 and ART558, which inhibit non-homologous end-joining (NHEJ) and micro-homology mediated end-joining (MMEJ). Adding AZD7648 alone improved gene insertion by 2- to 3-fold. Adding both ART558 and AZD7648 improved gene insertion but induced toxicity. ABCs edited in the presence of AZD7648 produced differentiated airway epithelial sheets with restored CFTR function after enrichment. Adding AZD7648 did not increase off-target editing. Further studies are necessary to validate if AZD7648 treatment enriches cells with oncogenic mutations.
PMID:39398224 | PMC:PMC11470261 | DOI:10.1016/j.omtn.2024.102339
Neonatal screening for cystic fibrosis in the Liege region : first evaluation after 4 years
Rev Med Liege. 2024 Oct;79(10):664-669.
ABSTRACT
Since January 2020, neonatal screening for cystic fibrosis (CF-NBS) has been implemented in the Wallonia-Brussels Federation. It's based on the immunoreactive trypsin (IRT1) assay between day 2 and day 4, associated with a 12 CFTR pathogenic variants analysis and with an IRT control on day 21. The aim of this study is to evaluate the performance of our CF-NBS in Liège according to the quality criteria defined by the European Cystic Fibrosis Society's working group on neonatal screening. After four years, 58.762 newborns have been screened. Nineteen children with cystic fibrosis were diagnosed : 14 by NBS, 3 following a meconium ileus, 1 by family history and 1 false negative diagnosed on clinical basis. Furthermore, 39 healthy carriers and 2 uncertain diagnosis (CFSPID) were identified. The sensitivity of CF NBS is 93,3 % (target ≥ 95 %), the positive predictive value (PPV) 17,7 % (target ≥ 30 %). Increasing the TIR1 threshold by 0,1 in 0,1 from P99 to P99,5, would be associated with a lower sensitivity and a non-significant improvement of PPV. A national assessment of CF NBS needs to be carried out.
PMID:39397555
Detection of pathogenic gene mutations in thirteen cases of congenital bilateral absence of vas deferens infertility patients
Beijing Da Xue Xue Bao Yi Xue Ban. 2024 Oct 18;56(5):763-774.
ABSTRACT
OBJECTIVE: To detect the cystic fibrosis transmembrane transduction regulator (CFTR) gene mutations and congenital bilateral absence of vas deferens (CBAVD) susceptibility gene mutations in patients with CBAVD, and to explore their association with the risk of CBAVD.
METHODS: Whole-exome sequencing and Sanger sequencing validation were conducted on the pathogenic genes CFTR, adhesion G protein-coupled receptor G2 (ADGRG2), sodium channel epithelial 1 subunit beta (SCNN1B), carbonic anhydrase 12 (CA12), and solute carrier family 9 member A3 (SLC9A3) in thirteen cases of isolated CBAVD patients. The polymorphic loci, intron and flanking sequences of CFTR gene were amplified by polymerase chain reaction (PCR) followed by Sanger sequencing. Bioinformatics methods were employed for conservative analysis and deleterious prediction of novel susceptibility gene mutations in CBAVD. Genetic analysis was performed on the pedigree of one out of thirteen patients with CBAVD to evaluate the risk of inheritance in offspring.
RESULTS: Exome sequencing revealed CFTR gene exon mutations in only six of the thirteen CBAVD patients, with six missense mutations c.2684G>A(p.Ser895Asn), c.4056G>C(p.Gln1352His), c.2812G>(p.Val938Leu), c.3068T>G(p.Ile1023Arg), c.374T>C(p.Ile125Thr), c.1666A>G(p.Ile556Val)), and one nonsense mutation (c.1657C>T(p.Arg553Ter). Among these six patients, two also had the CFTR homozygous p.V470 site, additionally, mutations in CFTR gene exon regions were not detected in the remaining seven patients. Within the thirteen CBAVD patients, three carried the homozygous p.V470 polymorphic site, four carried the 5T allele, two carried the TG13 allele, and ten carried the c.-966T>G site. Four CBAVD patients simultaneously carried 2-3 of the aforementioned CFTR gene mutation sites. Susceptibility gene mutations in CBAVD among the thirteen patients included one ADGRG2 missense mutation c.2312A>G(p.Asn771Ser), two SLC9A3 missense mutations c.2395T>C(p.Cys799Arg), c.493G>A(p.Val165Ile), one SCNN1B missense mutation c.1514G>A(p.Arg505His), and one CA12 missense mutation c.1061C>T (p.Ala354Val). Notably, the SLC9A3 gene c.493G>A (p.Val165Ile) mutation site was first identified in CBAVD patients. The five mutations exhibited an extremely low population mutation frequency in the gnomAD database, classifying them as rare mutations. Predictions from Mutation Taster and Polyphen-2 software indicated that the harmfulness level of the SLC9A3 gene c.493G>A (p.Val165Ile) site and the SCNN1B gene c.1514G>A (p.Arg505His) site were disease causing and probably damaging. The genetic analysis of one pedigree revealed that the c.1657C>T (p.Arg553Ter) mutation in the proband was a de novo mutation, as neither the proband's father nor mother carried this mutation. The proband and his spouse conceived a daughter through assisted reproductive technology, and the daughter inherited the proband's pathogenic mutation c.1657C>T (p.Arg553Ter).
CONCLUSION: CFTR gene mutations remain the leading cause of CBAVD in Chinese patients; however, the distribution and frequency of mutations differ from data reported in other domestic and international studies, highlighting the need to expand the CFTR mutation spectrum in Chinese CBAVD patients. The susceptibility genes ADGRG2, SLC9A3, SCNN1B, and CA12 may explain some cases of CBAVD without CFTR mutations. Given the lack of specific clinical manifestations in CBAVD patients, it is recommended that clinicians conduct further physical examinations and consider scrotal or transrectal ultrasound before making a defi-nitive diagnosis. It is advisable to employ CFTR gene mutation testing in preconception genetic screening to reduce the risk of CBAVD and cystic fibrosis in offspring.
PMID:39397452
Airway inflammation enhances the effectiveness of elexacaftor-tezacaftor-ivacaftor therapy for cystic fibrosis and CFTR(N1303K) mutation
Lancet Respir Med. 2024 Oct 9:S2213-2600(24)00305-9. doi: 10.1016/S2213-2600(24)00305-9. Online ahead of print.
NO ABSTRACT
PMID:39395437 | DOI:10.1016/S2213-2600(24)00305-9
Protein phosphatase 2A activators under investigation for smoking-related chronic obstructive pulmonary disease and related disorders
Expert Opin Investig Drugs. 2024 Oct 15:1-8. doi: 10.1080/13543784.2024.2416982. Online ahead of print.
ABSTRACT
INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is characterized by progressive inflammation during therapy. Cystic fibrosis (CF), alpha-one antitrypsin deficiency (AATD), and non-CF bronchiectasis are also chronic respiratory disorders with inflammation and progression that share many similarities with COPD. Therefore, various anti-inflammatory approaches are currently being investigated, and protein phosphatase 2A (PP2A) activators may represent one such approach.
AREAS COVERED: Systematic review of papers published from 2000-to date on the anti-inflammatory role of endogenous PP2A, the consequences of its inhibition by smoking, and the beneficial effects of its activation in COPD.
EXPERT OPINION: PP2A activation is a plausible therapeutic approach in COPD and related disorders, such as CF, AATD, and non-CF bronchiectasis, although the available evidence is still mostly experimental. Metformin repurposing and consideration of inhalation for some of the molecules discussed in this study are promising approaches.
PMID:39394816 | DOI:10.1080/13543784.2024.2416982
Immune Dysregulation in the Oral Cavity during Early SARS-CoV-2 Infection
J Dent Res. 2024 Oct 12:220345241271943. doi: 10.1177/00220345241271943. Online ahead of print.
ABSTRACT
Tissue-specific immune responses are critical determinants of health-maintaining homeostasis and disease-related dysbiosis. In the context of COVID-19, oral immune responses reflect local host-pathogen dynamics near the site of infection and serve as important "windows to the body," reflecting systemic responses to the invading SARS-CoV-2 virus. This study leveraged multiplex technology to characterize the salivary SARS-CoV-2-specific immunological landscape (37 cytokines/chemokines and 11 antibodies) during early infection. Cytokine/immune profiling was performed on unstimulated cleared whole saliva collected from 227 adult SARS-CoV-2+ participants and 37 controls. Statistical analysis and modeling revealed significant differential abundance of 25 cytokines (16 downregulated, 9 upregulated). Pathway analysis demonstrated early SARS-CoV-2 infection is associated with local suppression of oral type I/III interferon and blunted natural killer-/T-cell responses, reflecting a potential novel immune-evasion strategy enabling infection. This virus-associated immune suppression occurred concomitantly with significant upregulation of proinflammatory pathways including marked increases in the acute phase proteins pentraxin-3 and chitinase-3-like-1. Irrespective of SARS-CoV-2 infection, prior vaccination was associated with increased total α-SARS-CoV-2-spike (trimer), -S1 protein, -RBD, and -nucleocapsid salivary antibodies, highlighting the importance of COVID-19 vaccination in eliciting mucosal responses. Altogether, our findings highlight saliva as a stable and accessible biofluid for monitoring host responses to SARS-CoV-2 over time and suggest that oral-mucosal immune dysregulation is a hallmark of early SARS-CoV-2 infection, with possible implications for viral evasion mechanisms.
PMID:39394771 | DOI:10.1177/00220345241271943
Flow cytometry-assisted analysis of phenotypic maturation markers on an immortalized dendritic cell line
Methods Cell Biol. 2024;189:153-168. doi: 10.1016/bs.mcb.2024.05.008. Epub 2024 Jun 12.
ABSTRACT
Dendritic cells (DCs), and especially so conventional type I DCs (cDC1s), are fundamental regulators of anticancer immunity, largely reflecting their superior ability to engulf tumor-derived material and process it for cross-presentation on MHC Class I molecules to CD8+ cytotoxic T lymphocytes (CTLs). Thus, investigating key DC functions including (but not limited to) phagocytic capacity, expression of CTL-activating ligands on the cell surface, and cross-presentation efficacy is an important component of multiple immuno-oncology studies. Unfortunately, DCs are terminally differentiated cells, implying that they cannot be propagated indefinitely in vitro and hence must be generated ad hoc from circulating or bone marrow-derived precursors, which presents several limitations. Here, we propose a simple, cytofluorometric method to quantify phenotypic activation markers including CD80, CD86 and MHC class II molecules on the surface of a conditionally immortalized immature DC line that can be indefinitely propagated in vitro but also driven into maturation at will with a simple change in culture conditions. Upon appropriate scaling and automatization, this approach is compatible with high-throughput screening programs for the discovery of novel DC activators that do not suffer from batch variability and other limitations associated with the generation of fresh DCs.
PMID:39393881 | DOI:10.1016/bs.mcb.2024.05.008
A Non-natural Peptide Targeting the A-kinase Anchoring Function of PI3Kγ for Therapeutic cAMP Modulation in Pulmonary Cells
J Biol Chem. 2024 Oct 9:107873. doi: 10.1016/j.jbc.2024.107873. Online ahead of print.
ABSTRACT
A-kinase anchoring proteins (AKAPs) are key orchestrators of cyclic AMP (cAMP) signaling that act by recruiting protein kinase A (PKA) in proximity of its substrates and regulators to specific subcellular compartments. Modulation of AKAPs function offers the opportunity to achieve compartment-restricted modulation of the cAMP/PKA axis, paving the way to new targeted treatments. For instance, blocking the AKAP activity of PI3Kγ improves lung function by inducing cAMP-mediated bronchorelaxation, ion transport and anti-inflammatory responses. Here, we report the generation of a non-natural peptide, DRI-Pep #20, optimized to disrupt the AKAP function of PI3Kγ. DRI-Pep #20 mimicked the native interaction between the N-terminal domain of PI3Kγ and PKA, demonstrating nanomolar affinity for PKA, high resistance to protease degradation and high permeability to the pulmonary mucus barrier. DRI-Pep #20 triggered cAMP elevation both in vivo in the airway tract of mice upon intratracheal administration, and in vitro in bronchial epithelial cells of cystic fibrosis (CF) patients. In CF cells, DRI-Pep #20 rescued the defective function of the cAMP-operated channel cystic fibrosis conductance regulator (CFTR), by boosting the efficacy of approved CFTR modulators. Overall, this study unveils DRI-Pep #20 as a potent PI3Kγ/PKA disruptor for achieving therapeutic cAMP elevation in chronic respiratory disorders.
PMID:39393573 | DOI:10.1016/j.jbc.2024.107873