Cystic Fibrosis

New Aspects of Lung Transplantation: A Narrative Overview Covering Important Aspects of Perioperative Management

Sat, 2023-01-21 06:00

Life (Basel). 2022 Dec 28;13(1):92. doi: 10.3390/life13010092.

ABSTRACT

The management of lung transplant patients has continued to evolve in recent years. The year 2021 was marked by the publication of the International Consensus Recommendations for Anesthetic and Intensive Care Management of Lung Transplantation. There have been major changes in lung transplant programs over the last few years. This review will summarize the knowledge in anesthesia management of lung transplantation with the most recent data. It will highlight the following aspects which concern anesthesiologists more specifically: (1) impact of COVID-19, (2) future of transplantation for cystic fibrosis patients, (3) hemostasis management, (4) extracorporeal membrane oxygenation management, (5) early prediction of primary graft dysfunction, and (6) pain management.

PMID:36676041 | DOI:10.3390/life13010092

Categories: Literature Watch

Lignin-Modifying Enzymes in <em>Scedosporium</em> Species

Sat, 2023-01-21 06:00

J Fungi (Basel). 2023 Jan 12;9(1):105. doi: 10.3390/jof9010105.

ABSTRACT

Scedosporium species are usually soil saprophytes but some members of the genus such as S. apiospermum and S. aurantiacum have been regularly reported as causing human respiratory infections, particularly in patients with cystic fibrosis (CF). Because of their low sensitivity to almost all available antifungal drugs, a better understanding of the pathogenic mechanisms of these fungi is mandatory. Likewise, identification of the origin of the contamination of patients with CF may be helpful to propose prophylactic measures. In this aim, environmental studies were conducted demonstrating that Scedosporium species are abundant in human-made environments and associated with nutrient-rich substrates. Although their natural habitat remains unknown, there is accumulated evidence to consider them as wood-decaying fungi. This study aimed to demonstrate the ability of these fungi to utilize lignocellulose compounds, especially lignin, as a carbon source. First, the lignolytic properties of Scedosporium species were confirmed by cultural methods, and biochemical assays suggested the involvement of peroxidases and oxidases as lignin-modifying enzymes. Scedosporium genomes were then screened using tBLASTn searches. Fifteen candidate genes were identified, including four peroxidase and seven oxidase genes, and some of them were shown, by real-time PCR experiments, to be overexpressed in lignin-containing medium, thus confirming their involvement in lignin degradation.

PMID:36675925 | DOI:10.3390/jof9010105

Categories: Literature Watch

Additive Potentiation of R334W-CFTR Function by Novel Small Molecules

Sat, 2023-01-21 06:00

J Pers Med. 2023 Jan 1;13(1):102. doi: 10.3390/jpm13010102.

ABSTRACT

The R334W (c.1000C&gt;T, p.Arg334Trp) is a rare cystic fibrosis (CF)-causing mutation for which no causal therapy is currently approved. This mutation leads to a significant reduction of CF transmembrane conductance regulator (CFTR) channel conductance that still allows for residual function. Potentiators are small molecules that interact with CFTR protein at the plasma membrane to enhance CFTR-dependent chloride secretion, representing thus pharmacotherapies targeting the root cause of the disease. Here, we generated a new CF bronchial epithelial (CFBE) cell line to screen a collection of compounds and identify novel potentiators for R334W-CFTR. The active compounds were then validated by electrophysiological assays and their additive effects in combination with VX-770, genistein, or VX-445 were exploited in this cell line and further confirmed in intestinal organoids. Four compounds (LSO-24, LSO-25, LSO-38, and LSO-77) were active in the functional primary screen and their ability to enhance R334W-CFTR-dependent chloride secretion was confirmed using electrophysiological measurements. In silico ADME analyses demonstrated that these compounds follow Lipinski's rule of five and are thus suggested to be orally bioavailable. Dose-response relationships revealed nevertheless suboptimal efficacy and weak potency exerted by these compounds. VX-770 and genistein also displayed a small potentiation of R334W-CFTR function, while VX-445 demonstrated no potentiator activity for this mutation. In the R334W-expressing cell line, CFTR function was further enhanced by the combination of LSO-24, LSO-25, LSO-38, or LSO-77 with VX-770, but not with genistein. The efficacy of potentiator VX-770 combined with active LSO compounds was further confirmed in intestinal organoids (R334W/R334W genotype). Taken together, these molecules were demonstrated to potentiate R334W-CFTR function by a different mechanism than that of VX-770. They may provide a feasible starting point for the design of analogs with improved CFTR-potentiator activity.

PMID:36675763 | DOI:10.3390/jpm13010102

Categories: Literature Watch

Nebulized Menthol Impairs Mucociliary Clearance via TRPM8 and MUC5AC/MUC5B in Primary Airway Epithelial Cells

Sat, 2023-01-21 06:00

Int J Mol Sci. 2023 Jan 15;24(2):1694. doi: 10.3390/ijms24021694.

ABSTRACT

Flavorings enhance the palatability of e-cigarettes (e-cigs), with menthol remaining a popular choice among e-cig users. Menthol flavor remains one of the only flavors approved by the United States FDA for use in commercially available, pod-based e-cigs. However, the safety of inhaled menthol at the high concentrations used in e-cigs remains unclear. Here, we tested the effects of menthol on parameters of mucociliary clearance (MCC) in air-liquid interface (ALI) cultures of primary airway epithelial cells. ALI cultures treated with basolateral menthol (1 mM) showed a significant decrease in ciliary beat frequency (CBF) and airway surface liquid (ASL) volumes after 24 h. Menthol nebulized onto the surface of ALI cultures similarly reduced CBF and increased mucus concentrations, resulting in decreased rates of mucociliary transport. Nebulized menthol further increased the expression of mucin 5AC (MUC5AC) and mRNA expression of the inflammatory cytokines IL1B and TNFA. Menthol activated TRPM8, and the effects of menthol on MCC and inflammation could be blocked by a specific TRPM8 antagonist. These data provide further evidence that menthol at the concentrations used in e-cigs could cause harm to the airways.

PMID:36675209 | DOI:10.3390/ijms24021694

Categories: Literature Watch

Comparison of Virulence-Factor-Encoding Genes and Genotype Distribution amongst Clinical <em>Pseudomonas aeruginosa</em> Strains

Sat, 2023-01-21 06:00

Int J Mol Sci. 2023 Jan 9;24(2):1269. doi: 10.3390/ijms24021269.

ABSTRACT

Pseudomonas aeruginosa is an opportunistic pathogen encoding several virulence factors in its genome, which is well-known for its ability to cause severe and life-threatening infections, particularly among cystic fibrosis patients. The organism is also a major cause of nosocomial infections, mainly affecting patients with immune deficiencies and burn wounds, ventilator-assisted patients, and patients affected by other malignancies. The extensively reported emergence of multidrug-resistant (MDR) P. aeruginosa strains poses additional challenges to the management of infections. The aim of this study was to compare the incidence rates of selected virulence-factor-encoding genes and the genotype distribution amongst clinical multidrug-sensitive (MDS) and MDR P. aeruginosa strains. The study involved 74 MDS and 57 MDR P. aeruginosa strains and the following virulence-factor-encoding genes: lasB, plC H, plC N, exoU, nan1, pilA, and pilB. The genotype distribution, with respect to the antimicrobial susceptibility profiles of the strains, was also analyzed. The lasB and plC N genes were present amongst several P. aeruginosa strains, including all the MDR P. aeruginosa, suggesting that their presence might be used as a marker for diagnostic purposes. A wide variety of genotype distributions were observed among the investigated isolates, with the MDS and MDR strains exhibiting, respectively, 18 and 9 distinct profiles. A higher prevalence of genes determining the virulence factors in the MDR strains was observed in this study, but more research is needed on the prevalence and expression levels of these genes in additional MDR strains.

PMID:36674786 | DOI:10.3390/ijms24021269

Categories: Literature Watch

Phenotypic Alteration of an Established Human Airway Cell Line by Media Selection

Sat, 2023-01-21 06:00

Int J Mol Sci. 2023 Jan 8;24(2):1246. doi: 10.3390/ijms24021246.

ABSTRACT

Cystic Fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), a chloride/bicarbonate channel. Many studies utilize human airway cell models (cell lines and primary cells) to study different aspects of CFTR biology. Media selection can alter the growth and differentiation of primary cells, yet the impact on stable airway cell lines is unclear. To determine the impact of media and growth conditions on CFBE41o- cells stably transduced with wild-type or F508del CFTR, we examined four commonly used growth media, measuring epithelial and mesenchymal markers, as well as CFTR expression, maturation, and function. The selection of growth media altered the expression of epithelial and mesenchymal markers in the cell lines, and significantly impacted CFTR expression and subsequent function. These results highlight the importance of media selection to CFTR and cell line behavior and should be considered in both studies of primary human airway cells and stable cell lines.

PMID:36674762 | DOI:10.3390/ijms24021246

Categories: Literature Watch

Immunogenicity and Safety of the BNT162b2 COVID-19 Vaccine in Patients with Cystic Fibrosis with or without Lung Transplantation

Sat, 2023-01-21 06:00

Int J Mol Sci. 2023 Jan 4;24(2):908. doi: 10.3390/ijms24020908.

ABSTRACT

Cystic fibrosis (CF) is characterized by a progressive decline in lung function, which may be further impaired by viral infections. CF is therefore considered a comorbidity of coronavirus disease 2019 (COVID-19), and SARS-CoV-2 vaccine prioritization has been proposed for patients with (pw)CF. Poor outcomes have been reported in lung transplant recipients (LTR) after SARS-CoV-2 infections. LTR have also displayed poor immunization against SARS-CoV-2 after mRNA-based BNT162b2 vaccination, especially in those undergoing immunosuppressive treatment, mostly those receiving mycophenolate mofetil (MMF) therapy. We aimed to determine here the immunogenicity and safety of the BNT162b2 vaccine in our cohort of 260 pwCF, including 18 LTR. Serum levels of neutralizing anti-SARS-CoV-2 IgG and IgA antibodies were quantified after the administration of two doses. PwCF displayed a vaccine-induced IgG and IgA antiviral response comparable with that seen in the general population. We also observed that the immunogenicity of the BNT162b2 vaccine was significantly impaired in the LTR subcohort, especially in patients undergoing MMF therapy. The BNT162b2 vaccine also caused minor adverse events as in the general population, mostly after administration of the second dose. Overall, our results justify the use of the BNT162b2 vaccine in pwCF and highlight the importance of a longitudinal assessment of the anti-SARS-CoV-2 IgG and IgA neutralizing antibody response to COVID-19 vaccination.

PMID:36674422 | DOI:10.3390/ijms24020908

Categories: Literature Watch

Molecular Profiling of Tissue Samples with Chronic Rejection from Patients with Chronic Lung Allograft Dysfunction: A Pilot Study in Cystic Fibrosis Patients

Sat, 2023-01-21 06:00

Biomolecules. 2023 Jan 3;13(1):97. doi: 10.3390/biom13010097.

ABSTRACT

Chronic rejection (CR) is the main culprit for reduced survival and quality of life in patients undergoing lung transplantation (Ltx). High-throughput approaches have been used to unveil the molecular pathways of CR, mainly in the blood and/or in bronchoalveolar lavage. We hypothesized that a distinct molecular signature characterizes the biopsies of recipients with clinically confirmed histological signs of CR. Eighteen cystic fibrosis patients were included in the study and RNA sequencing was performed in 35 scheduled transbronchial biopsies (TBBs): 5 with acute cellular rejection, 9 with CR, and 13 without any sign of post-LTx complication at the time of biopsy; 8 donor lung samples were used as controls. Three networks with 33, 26, and 36 differentially expressed genes (DEGs) were found in TBBs with CR. Among these, seven genes were common to the identified pathways and possibly linked to CR and five of them (LCN2, CCL11, CX3CL1, CXCL12, MUC4) were confirmed by real-time PCR. Immunohistochemistry was significant for LCN2 and MUC4. This study identified a typical gene expression pattern in TBBs with histological signs of CR and the LCN2 gene appeared to play a central role. Thus, it could be crucial in CR pathophysiology.

PMID:36671482 | DOI:10.3390/biom13010097

Categories: Literature Watch

Evaluation of the Efficiency of Random and Diblock Methacrylate-Based Amphiphilic Cationic Polymers against Major Bacterial Pathogens Associated with Cystic Fibrosis

Sat, 2023-01-21 06:00

Antibiotics (Basel). 2023 Jan 8;12(1):120. doi: 10.3390/antibiotics12010120.

ABSTRACT

Cystic fibrosis (CF) is associated with repeated lung bacterial infection, mainly by Pseudomonas aeruginosa, Staphylococcus aureus, and Mycobacterium abscessus, all known to be or becoming resistant to several antibiotics, often leading to therapeutic failure and death. In this context, antimicrobial peptides and antimicrobial polymers active against resistant strains and less prompt to cause resistance, appear as a good alternative to conventional antibiotics. In the present study, methacrylate-based copolymers obtained by radical chemistry were evaluated against CF-associated bacterial strains. Results showed that the type (Random versus Diblock) and the size of the copolymers affected their antibacterial activity and toxicity. Among the different copolymers tested, four (i.e., Random10200, Random15000, Random23900, and Diblock9500) were identified as the most active and the safest molecules and were further investigated. Data showed that they inserted into bacterial lipids, leading to a rapid membranolytic effect and killing of the bacterial. In relation with their fast bactericidal action and conversely to conventional antibiotics, those copolymers did not induce a resistance and remained active against antibiotic-resistant strains. Finally, the selected copolymers possessed a preventive effect on biofilm formation, although not exhibiting disruptive activity. Overall, the present study demonstrates that methacrylate-based copolymers are an interesting alternative to conventional antibiotics in the treatment of CF-associated bacterial infection.

PMID:36671321 | DOI:10.3390/antibiotics12010120

Categories: Literature Watch

Organoid Technology and Its Role for Theratyping Applications in Cystic Fibrosis

Sat, 2023-01-21 06:00

Children (Basel). 2022 Dec 20;10(1):4. doi: 10.3390/children10010004.

ABSTRACT

Cystic fibrosis (CF) is a autosomal recessive, multisystemic disease caused by different mutations in the CFTR gene encoding CF transmembrane conductance regulator. Although symptom management is important to avoid complications, the approval of CFTR modulator drugs in the clinic has demonstrated significant improvements by targeting the primary molecular defect of CF and thereby preventing problems related to CFTR deficiency or dysfunction. CFTR modulator therapies have positively changed the patients' quality of life, especially for those who start their use at the onset of the disease. Due to early diagnosis with the implementation of newborn screening programs and considerable progress in the treatment options, nowadays pediatric mortality was dramatically reduced. In any case, the main obstacle to treat CF is to predict the drug response of patients due to genetic complexity and heterogeneity. Advances in 3D culture systems have led to the extrapolation of disease modeling and individual drug response in vitro by producing mini organs called "organoids" easily obtained from nasal and rectal mucosa biopsies. In this review, we focus primarily on patient-derived intestinal organoids used as in vitro model for CF disease. Organoids combine high-validity of outcomes with a high throughput, thus enabling CF disease classification, drug development and treatment optimization in a personalized manner.

PMID:36670555 | DOI:10.3390/children10010004

Categories: Literature Watch

Longitudinal effects of elexacaftor/tezacaftor/ivacaftor on liver tests at a large single adult cystic fibrosis centre

Fri, 2023-01-20 06:00

J Cyst Fibros. 2023 Jan 18:S1569-1993(23)00008-5. doi: 10.1016/j.jcf.2023.01.007. Online ahead of print.

ABSTRACT

BACKGROUND: Elexacaftor/tezacaftor/ivacaftor (E/T/I) therapy has resulted in substantial improvements in health status for many with cystic fibrosis. Monitoring of liver tests is recommended due to observed rises in transaminases in trials and cases of hepatotoxicity. Comprehensive data in large populations of unselected individuals and those with established CF related liver disease (CFLD) is lacking.

METHODS: Patients prescribed E/T/I at a large, adult centre had liver tests monitored at least 3 monthly for 12 months. Changes in individual liver tests were analysed and abnormalities were compared in those with and without CFLD.

RESULTS: 255 of 267 eligible patients were included. Mild rises in median ALT, AST and bilirubin from baseline to 3 months (all p < 0.001) within normal limits were noted which were sustained. There were no differences in changes in liver tests between those with or without CFLD. There was a significant difference in alkaline phosphatase for those with raised levels at baseline versus those with normal baseline level (-18.5 vs +2.0 IU/L, p = 0.002). Clinically significant rises in ALT and AST occurred in 8 (3.1%) and 6 (2.4%) cases respectively, with derangements in 2 individuals attributed to therapy.

CONCLUSIONS: E/T/I leads to a mild, likely clinically insignificant increase in ALT, AST and bilirubin after 3 months which is sustained but does not appear to increase further in the vast majority. Underlying CFLD should not be a barrier to treatment. Although there was a reduction in ALP when elevated at baseline, this was not unique to those with pre-existing CFLD.

PMID:36669962 | DOI:10.1016/j.jcf.2023.01.007

Categories: Literature Watch

Bone health outcomes in post-lung transplant patients with cystic fibrosis

Fri, 2023-01-20 06:00

J Cyst Fibros. 2023 Jan 18:S1569-1993(23)00005-X. doi: 10.1016/j.jcf.2023.01.003. Online ahead of print.

ABSTRACT

BACKGROUND: Osteoporosis is a common comorbidity in patients with cystic fibrosis (CF). Although lung transplantation (LTx) improves quality of life of CF patients, there is little research examining long-term bone health outcomes following LTx in these patients.

METHODS: Data were collected on 59 patients who underwent LTx between 2006 and 2019, including 30 with CF and 29 without CF. We compared baseline characteristics, long-term bone mineral density (BMD) trends, and fracture incidence between the two patient populations, and examined factors associated with post-LTx fractures in CF patients.

RESULTS: Compared with non-CF patients, patients with CF were younger, had lower body mass index, and lower baseline BMD Z-scores at the lumbar spine, femoral neck, and total hip (all p<0.001). BMD at all sites declined in both groups in the first year post-LTx. In subsequent years, CF patients exhibited better BMD recovery relative to pre-transplantation, but continued to have lower BMD post-LTx. Post-transplant fractures occurred in 30% and 34% of CF and non-CF patients, respectively. CF patients who developed fractures after LTx had significantly lower BMD and lower pre-transplantation percent predicted forced expiratory volume in one second (FEV1%).

CONCLUSIONS: Although CF patients exhibit better BMD recovery following LTx compared to their non-CF counterparts, CF patients start with significantly lower pre-LTx BMD and experience a similarly high rate of post-LTx fractures. These findings highlight the unique contribution of the CF disease process to bone health, as well as a clear need for better prevention and treatment of osteoporosis in CF patients before and after LTx.

PMID:36669961 | DOI:10.1016/j.jcf.2023.01.003

Categories: Literature Watch

Improved glucose tolerance after initiation of Elexacaftor / Tezacaftor / Ivacaftor in adults with cystic fibrosis

Fri, 2023-01-20 06:00

J Cyst Fibros. 2023 Jan 18:S1569-1993(23)00006-1. doi: 10.1016/j.jcf.2023.01.004. Online ahead of print.

ABSTRACT

BACKGROUND: The novel triple CFTR modulator therapy Elexacaftor/Tezacaftor/Ivacaftor (ELX/TEZ/IVA) improves lung function, body mass index (BMI), sinus clearance, and quality of life in patients with cystic fibrosis. Whether treatment with ELX/TEZ/IVA is associated with improved glucose tolerance is unknown.

METHODS: This cohort study included adults with CF and at least one copy of F508del.. Study assessments before treatment and at least 3 months after ELX/TEZ/IVA initiation included an oral glucose tolerance test (OGTT) with glucose and insulin measurements, BMI, lung function test, and sweat chloride levels. We used an analysis of response profiles to calculate changes in outcomes.

RESULTS: 33 patients (27.8 ± 6.3 years; 73% male; 64% F508del homozygous) were included. After a median of 184 [IQR, 107 - 278] days following treatment initiation 16 (48.5%) patients improved their glucose tolerance category, while 13 (39.4%) remained unchanged and 4 (12.1%) deteriorated. Overall, 60, 90 and 120 min OGTT glycemia decreased significantly from 11.9 ± 2.7 mmol/l to 10.6 ± 2.8 mmol/l (p = 0.012), 10.4 ± 3.0 mmol/l to 8.4 ± 3.6 mmol/l (p = 0.002) and 7.3 ± 3.1 mmol/l to 5.7 ± 3.0 mmol/l (p = 0.012). HbA1c levels also improved significantly, from 5.50±0.24% to 5.39±0.25% (p = 0.039).

CONCLUSION: In adult patients with CF and at least one copy of F508del, treatment with the triple CFTR modulator was associated with possible improvement of glucose tolerance without increases of insulin secretion. Early initiation of treatment as assessed through long-term prospective trials is mandatory to demonstrate if decreased glucose control is preventable or even reversible.

PMID:36669960 | DOI:10.1016/j.jcf.2023.01.004

Categories: Literature Watch

Codelivery of synergistic antimicrobials with polyelectrolyte nanocomplexes to treat bacterial biofilms and lung infections

Fri, 2023-01-20 06:00

Sci Adv. 2023 Jan 20;9(3):eade8039. doi: 10.1126/sciadv.ade8039. Epub 2023 Jan 20.

ABSTRACT

Bacterial biofilm infections, particularly those of Pseudomonas aeruginosa (PA), have high rates of antimicrobial tolerance and are commonly found in chronic wound and cystic fibrosis lung infections. Combination therapeutics that act synergistically can overcome antimicrobial tolerance; however, the delivery of multiple therapeutics at relevant dosages remains a challenge. We therefore developed a nanoscale drug carrier for antimicrobial codelivery by combining approaches from polyelectrolyte nanocomplex (NC) formation and layer-by-layer electrostatic self-assembly. This strategy led to NC drug carriers loaded with tobramycin antibiotics and antimicrobial silver nanoparticles (AgTob-NCs). AgTob-NCs displayed synergistic enhancements in antimicrobial activity against both planktonic and biofilm PA cultures, with positively charged NCs outperforming negatively charged formulations. NCs were evaluated in mouse models of lung infection, leading to reduced bacterial burden and improved survival outcomes. This approach therefore shows promise for nanoscale therapeutic codelivery to treat recalcitrant bacterial infections.

PMID:36662850 | DOI:10.1126/sciadv.ade8039

Categories: Literature Watch

Effects of CFTR modulators on serum biomarkers of liver fibrosis in children with cystic fibrosis

Fri, 2023-01-20 06:00

Hepatol Commun. 2023 Jan 20;7(2):e0010. doi: 10.1097/HC9.0000000000000010.

ABSTRACT

The cystic fibrosis (CF) transmembrane conductance regulator corrector/potentiator combinations lumacaftor/ivacaftor and elexacaftor/tezacaftor/ivacaftor improve sweat chloride, pulmonary function, and nutrition. Yet it is unclear whether they may also impact the progression of liver fibrosis, which is a substantial source of morbidity and mortality for patients with CF. We conducted a retrospective, single-center analysis of children and adolescents with CF treated with lumacaftor/ivacaftor and/or elexacaftor/tezacaftor/ivacaftor therapy, focusing on alterations in liver function tests and fibrosis indices using previously-established thresholds that corresponded with increased liver elastography. In pairwise comparisons of before and during treatment timepoints, we found that those with CF-associated liver involvement experienced significant decreases in gamma-glutamyl transferase, aspartate aminotransferase-to-platelet index, and gamma-glutamyl transferase-to-platelet ratio while on lumacaftor/ivacaftor. These differences were not observed in patients treated with elexacaftor/tezacaftor/ivacaftor, nor were they observed in patients without underlying CF-associated liver disease. These results provide the first evidence that lumacaftor/ivacaftor may improve liver fibrosis in children and adolescents with CF and suggest it may be beneficial in the treatment of CF-associated liver disease.

PMID:36662672 | DOI:10.1097/HC9.0000000000000010

Categories: Literature Watch

Induction of killing of Mycobacterium avium subsp. hominissuis in macrophages by cytokine stimulated innate-like lymphoid cells is negatively affected by the pathogen

Fri, 2023-01-20 06:00

Int Microbiol. 2023 Jan 20. doi: 10.1007/s10123-023-00326-4. Online ahead of print.

ABSTRACT

Mycobacterium avium subsp. hominissuis (MAH) is a common environmental bacterium that causes infection in immunocompromised patients such as those with HIV/AIDS, or patients with chronic lung disease such as cystic fibrosis. There are many strains of MAH with varying levels of virulence. Infection with MAH strains 100 and 104 has been associated with different immune responses in mice and outcome of the disease. While MAH 100 infection tends to be cleared from mice, MAH 104 is virulent and grows in host tissue. What is currently unknown are the mechanisms related to this difference in host defense and virulence. Our hypothesis is that differences in circulating innate lymphocytes response are associated with increased protection from infection. Innate lymphoid cells (ILC) are lymphoid cells with an important role in regulation of innate immune systems. ILCs can be categorized into three subpopulations ILC1, ILC2, and ILC3 based on their cytokine production and regulatory transcription factors. Investigation was carried out on how macrophage anti-MAH response change depending on activation by primary mouse lymphocytes activated with IL-12, IL-33, and IL-23, triggering differentiation into ILC-like subpopulations. Our results do not affirm the role of any one ILC subpopulation in macrophage anti-M. avium ability. Our findings instead support the conclusion that MAH infection of macrophages suppresses the stimulatory function of ILCs.

PMID:36662342 | DOI:10.1007/s10123-023-00326-4

Categories: Literature Watch

Community composition shapes microbial-specific phenotypes in a cystic fibrosis polymicrobial model system

Fri, 2023-01-20 06:00

Elife. 2023 Jan 20;12:e81604. doi: 10.7554/eLife.81604. Online ahead of print.

ABSTRACT

Interspecies interactions can drive the emergence of unexpected microbial phenotypes that are not observed when studying monocultures. The cystic fibrosis (CF) lung consists of a complex environment where microbes, living as polymicrobial biofilm-like communities, are associated with negative clinical outcomes for persons with CF (pwCF). However, the current lack of in vitro models integrating the microbial diversity observed in the CF airway hampers our understanding of why polymicrobial communities are recalcitrant to therapy in this disease. Here, integrating computational approaches informed by clinical data, we built a mixed community of clinical relevance to the CF lung composed of Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus sanguinis and Prevotella melaninogenica. We developed and validated this model biofilm community with multiple isolates of these four genera. When challenged with tobramycin, a front-line antimicrobial used to treat pwCF, the microorganisms in the polymicrobial community show altered sensitivity to this antibiotic compared to monospecies biofilms. We observed that wild-type P. aeruginosa is sensitized to tobramycin in a mixed community versus monoculture, and this observation holds across a range of community relative abundances. We also report that LasR loss-of-function, a variant frequently detected in the CF airway, drives tolerance of P. aeruginosa to tobramycin specifically in the mixed community. Our data suggest that the molecular basis of this community-specific recalcitrance to tobramycin for the P. aeruginosa LasR mutant is increased production of phenazines. Our work support the importance of studying a clinically-relevant model polymicrobial biofilms to understand community-specific traits relevant to infections.

PMID:36661299 | DOI:10.7554/eLife.81604

Categories: Literature Watch

Gene, RNA, and ASO-based therapeutic approaches in Cystic Fibrosis

Thu, 2023-01-19 06:00

J Cyst Fibros. 2023 Jan 17:S1569-1993(22)01436-9. doi: 10.1016/j.jcf.2022.12.016. Online ahead of print.

ABSTRACT

Most people with Cystic Fibrosis (PwCF) harbor Cystic Fibrosis Transmembrane Conductance (CFTR) mutations that respond to highly effective CFTR modulators (HEM); however, a small fraction of non-responsive variants will require alternative approaches for treatment. Furthermore, the long-term goal to develop a cure for CF will require novel therapeutic strategies. Nucleic acid-based approaches offer the potential to address all CF-causing mutations and possibly a cure for all PwCF. In this minireview, we discuss current knowledge, recent progress, and critical questions surrounding the topic of Gene-, RNA-, and ASO-based therapies for the treatment of Cystic Fibrosis (CF).

PMID:36658041 | DOI:10.1016/j.jcf.2022.12.016

Categories: Literature Watch

Molecular Epidemiologic Investigation of <em>Mycobacterium intracellulare</em> subspecies <em>chimaera</em> Lung Infections at an Adult Cystic Fibrosis Program

Thu, 2023-01-19 06:00

Ann Am Thorac Soc. 2023 Jan 19. doi: 10.1513/AnnalsATS.202209-779OC. Online ahead of print.

ABSTRACT

RATIONALE: Outbreaks of nontuberculous mycobacteria (NTM) among people with cystic fibrosis (pwCF) have been reported at CF Centers with conflicting conclusions. Occurrence of NTM at the University of Vermont Medical Center Adult CF Program was investigated.

OBJECTIVES: Utilize the Healthcare-associated Links in Transmission of NTM (HALT NTM) toolkit to investigate healthcare-associated transmission and/or acquisition of NTM among pwCF having genetically similar NTM isolates.

METHODS: Whole genome sequencing (WGS) of NTM isolates from 23 pwCF was conducted to identify genetically similar isolate clusters (≤30 single nucleotide polymorphism differences). Epidemiological investigation, comparison of respiratory and environmental isolates, and home residence watershed mapping were analyzed.

RESULTS: WGS analysis revealed 2 clusters of NTM (Mycobacterium avium and Mycobacterium intracellulare ssp. chimaera) among pwCF. Epidemiologic investigation demonstrated opportunities for healthcare-associated transmission within both clusters. Environmental M. avium isolates from the healthcare setting revealed no genetic similarity to respiratory isolates. However, M. intracellulare ssp. chimaera respiratory isolates revealed greater genetic similarity to a hospital water biofilm isolate than to each other. Neither cluster had all subjects residing in the same watershed.

CONCLUSIONS: This study suggests healthcare-associated transmission of M. avium among pwCF is unlikely at UVMC, but supports healthcare-associated environmental acquisition of M. intracellulare ssp. chimaera. Presence of genetically similar isolates alone is insufficient to confirm healthcare-associated transmission and/or acquisition. The HALT NTM toolkit standardizes outbreak investigation with genetic analysis, epidemiologic investigation, healthcare environmental sampling, and home of residence watershed identification to test the frequency and nature of healthcare-associated NTM transmission among pwCF.

PMID:36656594 | DOI:10.1513/AnnalsATS.202209-779OC

Categories: Literature Watch

Home Based Rehabilitation in Children and Adolescents with Cystic Fibrosis: A Systematic Review with Meta-Analysis and Grade Recommendations

Thu, 2023-01-19 06:00

Phys Occup Ther Pediatr. 2023 Jan 18:1-20. doi: 10.1080/01942638.2023.2169093. Online ahead of print.

ABSTRACT

OBJECTIVE: The objective of this study is to elucidate the effectiveness of home based rehabilitation (HBR) and compare its results with those obtained in conventional rehabilitation (CR) programs, carried out in clinics and/or outpatient clinics.

METHODS: Searches were conducted in five databases of randomized clinical trials. Study selection, data extraction, and assessment of the methodological quality of included studies were conducted independently by two reviewers, with discrepancies resolved by a third reviewer.

RESULTS: The results demonstrate post-intervention values favorable to the use of HBR when compared to control group in the outcomes of forced expiratory volume in 1 second (FEV1) (MD = 14% CI: 5.42 to 22.58, p = 0.001), forced vital capacity (FVC) (MD = 8.00% CI: 0.83 to 15.17, p = 0.03) and quality of life by the Cystic Fibrosis Questionnaire - revised in the categories (Child version score" (MD= 0.71%CI: 0.15 to 1.27, p = 0.01) and "Parent version score" (MD= 0.67%CI: 0.11 to 1.23, p = 0.02). Furthermore, we noticed an increase in the distance covered in the 6-minute walk test (MD= 34.75%CI: -8.00 to 77.50, p = 0.14), in favor of HBR.

CONCLUSIONS: We found that supervised or partially supervised HBR promotes improvements in FEV1, FVC and related quality of life in children and/or adolescents with cystic fibrosis.

PMID:36655279 | DOI:10.1080/01942638.2023.2169093

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