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BMC Pulmonary Medicine Jul 2023Neutrophils consume a large amount of energy when performing their functions. Compared with other white blood cells, neutrophils contain few mitochondria and mainly rely...
BACKGROUND
Neutrophils consume a large amount of energy when performing their functions. Compared with other white blood cells, neutrophils contain few mitochondria and mainly rely on glycolysis and gluconeogenesis to produce ATP. The inflammatory site is hypoxic and nutrient poor. Our aim is to study the role of abnormal adenosine metabolism of neutrophils in the asthmatic airway inflammation microenvironment.
METHOD
In this study, an asthma model was established by intratracheal instillation of Aspergillus fumigatus extract in Ecto-5'-Nucleotidase (CD73) gene-knockout and wild-type mice. Multiple analyses from bronchoalveolar lavage fluid (BALF) were used to determine the levels of cytokines and chemokines. Immunohistochemistry was used to detect subcutaneous fibrosis and inflammatory cell infiltration. Finally, adenosine 5'-(α, β-methylene) diphosphate (APCP), a CD73 inhibitor, was pumped subcutaneously before Aspergillus attack to observe the infiltration of inflammatory cells and subcutaneous fibrosis to clarify its therapeutic effect.
RESULT
PAS staining showed that CD73 knockout inhibited pulmonary epithelial cell proliferation and bronchial fibrosis induced by Aspergillus extract. The genetic knockdownof CD73 significantly reduced the production of Th2 cytokines, interleukin (IL)-4, IL-6, IL-13, chemokine (C-C motif) ligand 5 (CCL5), eosinophil chemokine, neutrophil IL-17, and granulocyte colony-stimulating factor (G-CSF). In addition, exogenous adenosine supplementation increased airway inflammation. Finally, the CD73 inhibitor APCP was administered to reduce inflammation and subcutaneous fibrosis.
CONCLUSION
Elevated adenosine metabolism plays an inflammatory role in asthma, and CD73 could be a potential therapeutic target for asthma.
Topics: Animals; Mice; Neutrophils; Aspergillus fumigatus; Adenosine; Asthma; Cytokines; Inflammation; Chemokines; Bronchoalveolar Lavage Fluid; Plant Extracts; Airway Remodeling
PubMed: 37452319
DOI: 10.1186/s12890-023-02553-x -
Pathogens (Basel, Switzerland) Oct 2023Infections due to the species constitute an important challenge for human health. Invasive aspergillosis represents a life-threatening disease, mostly in patients with... (Review)
Review
Infections due to the species constitute an important challenge for human health. Invasive aspergillosis represents a life-threatening disease, mostly in patients with immune defects. Drugs used for fungal infections comprise amphotericin B, triazoles, and echinocandins. However, in the last decade, an increased emergence of azole-resistant strains has been reported, principally belonging to species. Therefore, both the early diagnosis of aspergillosis and its epidemiological surveillance are very important to establish the correct antifungal therapy and to ensure a successful patient outcome. In this paper, a literature review is performed to analyze the prevalence of antifungal resistance in European countries. Amphotericin B resistance is observed in 2.6% and 10.8% of isolates in Denmark and Greece, respectively. A prevalence of 84% of amphotericin B-resistant isolates is reported in France, followed by 49.4%, 35.1%, 21.7%, and 20% in Spain, Portugal, Greece, and amphotericin B resistance of isolates is observed in Greece and Belgium with a prevalence of 75% and 12.8%, respectively. The prevalence of triazole resistance of isolates, the most studied mold obtained from the included studies, is 0.3% in Austria, 1% in Greece, 1.2% in Switzerland, 2.1% in France, 3.9% in Portugal, 4.9% in Italy, 5.3% in Germany, 6.1% in Denmark, 7.4% in Spain, 8.3% in Belgium, 11% in the Netherlands, and 13.2% in the United Kingdom. The mechanism of resistance is mainly driven by the TR/L98H mutation. In Europe, no in vivo resistance is reported for echinocandins. Future studies are needed to implement the knowledge on the spread of drug-resistant spp. with the aim of defining optimal treatment strategies.
PubMed: 38003770
DOI: 10.3390/pathogens12111305 -
European Journal of Immunology Oct 2023Alveolar macrophages (alvMs) play an important role for maintenance of lung function by constant removal of cellular debris in the alveolar space. They further...
Alveolar macrophages (alvMs) play an important role for maintenance of lung function by constant removal of cellular debris in the alveolar space. They further contribute to defense against microbial or viral infections and limit tissue damage during acute lung injury. alvMs arise from embryonic progenitor cells, seed the alveoli before birth, and have life-long self-renewing capacity. However, recruited monocytes may also help to restore the alvM population after depletion caused by toxins or influenza virus infection. At present, the population dynamics and cellular plasticity of alvMs during allergic lung inflammation is poorly defined. To address this point, we used a mouse model of Aspergillus fumigatus-induced allergic lung inflammation and observed that Th2-derived IL-4 and IL-13 caused almost complete disappearance of alvMs. This effect required STAT6 expression in alvMs and also occurred in various other settings of type 2 immunity-mediated lung inflammation or administration of IL-4 complexes to the lung. In addition, Th2 cells promoted conversion of alvMs to alternatively activated macrophages and multinucleated giant cells. Given the well-established role of alvMs for maintenance of lung function, this process may have implications for resolution of inflammation and tissue homeostasis in allergic asthma.
Topics: Mice; Animals; Macrophages, Alveolar; Interleukin-4; Lung; Asthma; Inflammation; Pneumonia; Pulmonary Eosinophilia
PubMed: 37452620
DOI: 10.1002/eji.202350475 -
Seminars in Respiratory and Critical... Feb 2024Chronic pulmonary aspergillosis (CPA) refers to a number of clinical syndromes resulting from the presence and local proliferation of organisms in the lungs of patients...
Chronic pulmonary aspergillosis (CPA) refers to a number of clinical syndromes resulting from the presence and local proliferation of organisms in the lungs of patients with chronic lung disease. CPA is more common than was realized two decades ago. Recognition remains poor, despite recent studies from many countries highlighting the high prevalence in at-risk populations. In low- and middle-income countries, CPA may be misdiagnosed and treated as tuberculosis (TB). In addition, CPA may develop following successful TB treatment. The coronavirus disease pandemic has resulted in significant disruption to provision of TB care, likely leading to more extensive lung damage, which could increase the risk for CPA.Although CPA refers to various syndromes, the classic presentation is that of chronic cavitary pulmonary aspergillosis, which manifests as one or more progressive cavities with or without a fungal ball, accompanied by systemic and respiratory symptoms for at least 3 months. Diagnosis relies on immunoglobulin G in serum, as sputum culture lacks sensitivity. Differential diagnosis includes mycobacterial infection, bacterial lung abscess or necrotizing pneumonia, lung cancer, and endemic fungi.The aim of antifungal treatment in CPA is to improve symptoms and quality of life, and to halt progression, and possibly reverse radiological changes. Current recommendations suggest treatment for 6 months, although in practice many patients remain on long-term treatment. Improvement may manifest as weight gain and improvement of symptoms such as productive cough, hemoptysis, and fatigue. Surgical management should be considered in cases of diagnostic uncertainty, in significant hemoptysis, and when there is concern for lack of response to therapy. Itraconazole and voriconazole are the first-line azoles, with more experience now accumulating with posaconazole and isavuconazole. Side effects are frequent and careful monitoring including therapeutic drug monitoring is essential. Intravenous antifungals such as echinocandins and amphotericin B are used in cases of azole intolerance or resistance, which often develop on treatment. Relapse is seen after completion of antifungal therapy in around 20% of cases, mostly in bilateral, high-burden disease.Several research priorities have been identified, including characterization of immune defects and genetic variants linked to CPA, pathogenetic mechanisms of adaptation in the lung environment, the contribution of non- species, and the role of new antifungal agents, immunotherapy, and combination therapy.
Topics: Humans; Antifungal Agents; Hemoptysis; Quality of Life; Pulmonary Aspergillosis; Aspergillus; Chronic Disease; Azoles; Persistent Infection
PubMed: 38154471
DOI: 10.1055/s-0043-1776914 -
Clinical Infectious Diseases : An... Jul 2023Invasive aspergillosis (IA) by a triazole-resistant Aspergillus fumigatus is associated with high mortality. Real-time resistance detection will result in earlier...
BACKGROUND
Invasive aspergillosis (IA) by a triazole-resistant Aspergillus fumigatus is associated with high mortality. Real-time resistance detection will result in earlier initiation of appropriate therapy.
METHODS
In a prospective study, we evaluated the clinical value of the AsperGenius polymerase chain reaction (PCR) assay in hematology patients from 12 centers. This PCR assay detects the most frequent cyp51A mutations in A. fumigatus conferring azole resistance. Patients were included when a computed tomography scan showed a pulmonary infiltrate and bronchoalveolar fluid (BALf) sampling was performed. The primary end point was antifungal treatment failure in patients with azole-resistant IA.
RESULTS
Of 323 patients enrolled, complete mycological and radiological information was available for 276 (94%), and probable IA was diagnosed in 99/276 (36%). Sufficient BALf for PCR testing was available for 293/323 (91%). Aspergillus DNA was detected in 116/293 (40%) and A. fumigatus DNA in 89/293 (30%). The resistance PCR was conclusive in 58/89 (65%) and resistance detected in 8/58 (14%). Two had a mixed azole-susceptible/azole-resistant infection. In the 6 remaining patients, treatment failure was observed in 1. Galactomannan positivity was associated with mortality (P = .004) while an isolated positive Aspergillus PCR was not (P = .83).
CONCLUSIONS
Real-time PCR-based resistance testing may help to limit the clinical impact of triazole resistance. In contrast, the clinical impact of an isolated positive Aspergillus PCR on BALf seems limited. The interpretation of the EORTC/MSGERC PCR criterion for BALf may need further specification (eg, minimum cycle threshold value and/or PCR positive on >1 BALf sample).
Topics: Humans; Prospective Studies; Invasive Pulmonary Aspergillosis; Azoles; Aspergillosis; Aspergillus; Aspergillus fumigatus; Invasive Fungal Infections; Real-Time Polymerase Chain Reaction; Triazoles; Antifungal Agents; Drug Resistance, Fungal
PubMed: 36905147
DOI: 10.1093/cid/ciad141 -
Journal of Ocular Pharmacology and... 2024To characterize the efficiency of glabridin alone and in combination with clinical antifungals in keratitis. The broth microdilution method was performed to...
To characterize the efficiency of glabridin alone and in combination with clinical antifungals in keratitis. The broth microdilution method was performed to investigate whether glabridin exerted an antifungal role on planktonic cells and immature and mature biofilm. Antifungal mechanism was evaluated by Sorbitol and Ergosterol Assays. The synergistic effect of glabridin and antifungals was assessed through the checkerboard microdilution method and time-killing test. Regarding anti-inflammatory role, inflammatory substances induced by were assessed by real-time quantitative polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay. Drug toxicity was assessed by Draize test . Macrophage phenotypes were examined by flow cytometry. Regarding antifungal activity, glabridin destroyed fungal cell wall and membrane on planktonic cells and suppressed immature and mature biofilm formation. After combining with natamycin or amphotericin B, glabridin possessed a potent synergistic effect against . Regarding anti-inflammatory aspects, Dectin-1, toll‑like receptor (TLR)-2 and TLR-4 expression of human corneal epithelial cells were significantly elevated after challenge and reduced by glabridin. The elevated expression of interleukin-1β and tumor necrosis factor-alpha induced by or corresponding agonists were reversed by glabridin, equivalent to the effect of corresponding inhibitors. Glabridin could also contribute to anti-inflammation by downregulating inflammatory mediator expression to suppress macrophage infiltration. Glabridin contributed to fungal clearance by destroying fungal cell wall and membrane, and disrupting biofilm. Combining glabridin with clinical antifungals was superior in reducing growth. Glabridin exerted an anti-inflammatory effect by downregulating proinflammatory substance expression and inhibiting macrophage infiltration, which provide a potential agent and treatment strategies for fungal keratitis.
Topics: Humans; Animals; Mice; Aspergillus fumigatus; Antifungal Agents; Aspergillosis; Keratitis; Eye Infections, Fungal; Anti-Inflammatory Agents; Mice, Inbred C57BL; Isoflavones; Phenols
PubMed: 38346287
DOI: 10.1089/jop.2023.0085 -
Mycoses Aug 2023Epidemiological knowledge is important to guide antifungal therapy.
BACKGROUND
Epidemiological knowledge is important to guide antifungal therapy.
OBJECTIVE
This multicentre study aimed to investigate the species distribution and antifungal susceptibility of Aspergillus isolates in Taiwan.
METHOD
Four hundred and ninety-two clinical Aspergillus isolates, collected during 2016-2020, were identified by calmodulin sequencing and tested for antifungal susceptibility using CLSI M38-A3. The Cyp51A sequences of azole-resistant Aspergillus fumigatus and Aspergillus flavus isolates were analysed.
RESULTS
This collection comprised 30 species from eight Aspergillus sections-Flavi (33.5%), Nigri (26.0%), Fumigati (24.2%), Terrei (10.0%), Nidulantes (5.1%), Circumdati (0.8%), Restricti (0.2%) and Aspergillus (0.2%). Sections Fumigati, Flavi and Terrei were primarily represented by A. fumigatus (99.2%), A. flavus (95.8%) and A. terreus (100%), respectively. Section Nigri comprised nine species, mostly A. welwitschiae (60.2%), A. niger (12.5%), A. brunneoviolaceus (10.9%) and A. tubingensis (10.2%). A. fumigatus (39.6%) and A. flavus (26.4%) predominated among 53 isolates from lower respiratory samples, whereas section Nigri species (46.2%) and A. terreus (29.2%) predominated among 65 isolates from ear samples. Reduced susceptibility to amphotericin B (minimal inhibitory concentration (MIC) > 1 μg/mL) was noted in A. flavus (7.0%), A. terreus (6.1%), A. nidulans and section Circumdati (A. flocculosus, A. subramanianii and A. westerdijkiae) isolates. Acquired azole resistance was observed in seven A. fumigatus (5.9%), all of which carried TR /L98H or TR /L98H/S297T/F495I mutation, and three A. flavus (1.9%), one of which carried G441S mutation. Reduced susceptibility to itraconazole (MIC >1 μg/mL) was noted in 55.5% of section Nigri isolates, mainly in A. welwitschiae, A. niger and A. tubingensis, whereas A. brunneoviolaceus, A. aculeatinus and A. japonicus were hypersusceptible to azoles. Anidulafungin was active against all isolates except for one isolate.
CONCLUSIONS
This study depicted the molecular epidemiology and species-specific characteristics of Aspergillus in Taiwan, which aids in appropriate antifungal therapy and underlines the need of speciation and susceptibility testing of disease-causing Aspergillus.
Topics: Humans; Antifungal Agents; Taiwan; Aspergillus; Itraconazole; Azoles; Aspergillus fumigatus; Microbial Sensitivity Tests; Drug Resistance, Fungal; Fungal Proteins
PubMed: 37186489
DOI: 10.1111/myc.13593 -
Frontiers in Microbiology 2023, a prevalent saprophytic fungus in the atmosphere, is known to rapidly induce severe invasive aspergillosis (IA) upon inhalation of its conidia by humans or animals....
, a prevalent saprophytic fungus in the atmosphere, is known to rapidly induce severe invasive aspergillosis (IA) upon inhalation of its conidia by humans or animals. The mortality rate associated with IA exceeds 50%. The misuse of antifungal agents has contributed to the emergence of numerous highly pathogenic drug-resistant strains of . Our study found that the combination of domiphen and itraconazole had sound synergistic antimicrobial effects against wild-type and itraconazole-resistant and through MIC, FIC, plate inoculation, growth curve experiments, and infection model. Drug cytotoxicity and pharmacological tests for acute toxicity assays demonstrated that both itraconazole and domiphen showed minimal cytotoxicity and good biocompatibility. The transcriptome sequencing experiment demonstrated that domiphen exerted a suppressive effect on the expression of various genes, including those involved in drug efflux, redox regulation, and cellular membrane and cell wall remodeling. The present investigation explores the synergistic antimicrobial mechanisms of domiphen and itraconazole, encompassing three key aspects: (i) domiphen inhibited the efflux of itraconazole by reducing the expression of drug efflux-related genes, (ii) the combination has good ability to disrupt the cell membrane and cell wall, (iii) the combination also can remove biofilm more effectively. In summary, the utilization of domiphen as a synergist of itraconazole exhibited disruptive effects on the biofilm, cell wall, and cell membrane of . This subsequently led to a modified distribution of itraconazole within the fungal organism, ultimately resulting in enhanced antifungal efficacy. The results of this study may provide a new therapeutic strategy for the treatment of IA caused by drug-resistant .
PubMed: 38075870
DOI: 10.3389/fmicb.2023.1264586 -
Research in Veterinary Science Nov 2023Antifungal-resistant fungi, including Aspergillus fumigatus and other Aspergillus species, pose an urgent threat to human and animal health. Furthermore, the...
Antifungal-resistant fungi, including Aspergillus fumigatus and other Aspergillus species, pose an urgent threat to human and animal health. Furthermore, the environmental route of azole resistance selection due to the widespread use of azole fungicides in crop protection and other applications is a major public health issue. Although environmental surveillance of fungi is frequently performed in many zoological parks and wildlife rehabilitation centers, the antifungal susceptibility of recovered isolates is only rarely analyzed, which precludes a clear assessment of the threat posed by these fungi to captive animals. In this study, we assessed the presence of airborne azole-resistant Aspergillus spp., including the so-called 'cryptic species' (i.e., species which are phenotypically similar to more well-known aspergilli but clearly constitute different phylogenetic lineages) in a zoological park located in the city of Madrid, Spain. In general, our results revealed a low prevalence A. fumigatus and cryptic aspergilli with decreased susceptibility to azoles. However, we detected an A. fumigatus isolate with the TR/L98H mutation in the gene encoding the lanosterol 14α-demethylase (Cyp51A), consisting of a tandem repeat of 34 base pairs in the promoter region and a lysine to histidine substitution at codon 98. Notably, this TR/L98H mutation has been linked to the environmental route of azole resistance selection, thus highlighting the 'One Health' dimension of the emerging problem of antifungal resistance. In this context, continuous environmental surveillance of azole-resistant aspergilli in zoological parks and other similar animal facilities is recommended.
Topics: Animals; Humans; Aspergillus fumigatus; Azoles; Antifungal Agents; Phylogeny; Fungal Proteins; Aspergillus; Fungi; Mutation; Microbial Sensitivity Tests
PubMed: 37657393
DOI: 10.1016/j.rvsc.2023.104993 -
Microbiology Spectrum Aug 2023Invasive aspergillosis is initiated when Aspergillus fumigatus adheres to and invades the pulmonary epithelial cells that line the airways and alveoli. To gain deeper...
Invasive aspergillosis is initiated when Aspergillus fumigatus adheres to and invades the pulmonary epithelial cells that line the airways and alveoli. To gain deeper insight into how pulmonary epithelial cells respond to A. fumigatus invasion, we used transcriptome sequencing (RNA-seq) to determine the transcriptional response of the A549 type II alveolar epithelial cell line to infection with strains CEA10 and Af293, two clinical isolates of A. fumigatus. Upstream regulator analysis of the data indicated that while both strains activated virtually identical host cell signaling pathways after 16 h of infection, only strain CEA10 activated these pathways after 6 h of infection. Many of the pathways that were predicted to be activated by A. fumigatus, including the tumor necrosis factor (TNF), interleukin-1α (IL-1α), IL-1β, IL-17A, Toll-like receptor 2 (TLR2), and TLR4 pathways, are known to be critical for the host defense against this fungus. We also found that the platelet-derived growth factor BB (PDGF BB) and progesterone receptor (PGR) pathways were activated by A. fumigatus. Using pharmacologic inhibitors, we determined that blocking the PDGF receptor or PGR inhibited the endocytosis of both strains of A. fumigatus in an additive manner. Both the PDGF BB and PGR pathways are also predicted to be activated by infection of A549 cells with other molds, such as Rhizopus delemar and Rhizopus oryzae. Thus, these pathways may represent a common response of pulmonary epithelial cells to mold infection. Invasive aspergillosis is a deadly invasive fungal infection that initiates when Aspergillus fumigatus spores are inhaled and come into contact with the epithelial cells that line the airways and alveoli. Understanding this fungus-host interaction is important for the development of novel therapeutics. To gain a deeper understanding of how these airway epithelial cells respond to A. fumigatus during infection, we used RNA-seq to determine the transcriptional response of alveolar epithelial cells to infection with two different clinical isolates of A. fumigatus. Our analysis identified new host response pathways that have not previously been tied to infection with A. fumigatus. Pharmacological inhibition of two of these pathways inhibited the ability of A. fumigatus to invade airway epithelial cells. These two pathways are also predicted to be activated by infection with other filamentous fungi. Thus, these pathways may represent a common response of alveolar epithelial cells to mold infection.
Topics: Humans; Aspergillus fumigatus; Becaplermin; Aspergillosis; Epithelial Cells; Lung
PubMed: 37255456
DOI: 10.1128/spectrum.00084-23