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1.
Trends Microbiol ; 31(3): 222-224, 2023 03.
Article in English | MEDLINE | ID: covidwho-2314717

ABSTRACT

The distinct risk factors to deadly infections by Aspergillus fumigatus (Af) in intensive care unit (ICU) patients are well known; however, so far, the mechanistic link between these predisposing conditions has been unknown. Sarden et al. recently unraveled a shared B1a lymphocyte-natural antibody-neutrophil defense pathway to Af, opening new perspectives in diagnostics and therapeutics.


Subject(s)
Aspergillosis , Humans , Aspergillus , Neutrophils , Risk Factors , Aspergillus fumigatus
2.
mBio ; 14(2): e0033923, 2023 04 25.
Article in English | MEDLINE | ID: covidwho-2308144

ABSTRACT

Invasive fungal infections are a leading cause of death in immunocompromised patients. Current therapies have several limitations, and innovative antifungal agents are critically needed. Previously, we identified the fungus-specific enzyme sterylglucosidase as essential for pathogenesis and virulence of Cryptococcus neoformans and Aspergillus fumigatus (Af) in murine models of mycoses. Here, we developed Af sterylglucosidase A (SglA) as a therapeutic target. We identified two selective inhibitors of SglA with distinct chemical scaffolds that bind in the active site of SglA. Both inhibitors induce sterylglucoside accumulation and delay filamentation in Af and increase survival in a murine model of pulmonary aspergillosis. Structure-activity relationship (SAR) studies identified a more potent derivative that enhances both in vitro phenotypes and in vivo survival. These findings support sterylglucosidase inhibition as a promising antifungal approach with broad-spectrum potential. IMPORTANCE Invasive fungal infections are a leading cause of death in immunocompromised patients. Aspergillus fumigatus is a fungus ubiquitously found in the environment that, upon inhalation, causes both acute and chronic illnesses in at-risk individuals. A. fumigatus is recognized as one of the critical fungal pathogens for which a substantive treatment breakthrough is urgently needed. Here, we studied a fungus-specific enzyme, sterylglucosidase A (SglA), as a therapeutic target. We identified selective inhibitors of SglA that induce accumulation of sterylglucosides and delay filamentation in A. fumigatus and increase survival in a murine model of pulmonary aspergillosis. We determined the structure of SglA, predicted the binding poses of these inhibitors through docking analysis, and identified a more efficacious derivative with a limited SAR study. These results open several exciting avenues for the research and development of a new class of antifungal agents targeting sterylglucosidases.


Subject(s)
Aspergillosis , Invasive Fungal Infections , Pulmonary Aspergillosis , Animals , Mice , Aspergillus fumigatus/genetics , Antifungal Agents/pharmacology , Disease Models, Animal , Aspergillosis/drug therapy , Aspergillosis/microbiology , Pulmonary Aspergillosis/drug therapy
3.
Rev Esp Anestesiol Reanim (Engl Ed) ; 69(9): 592-596, 2022 11.
Article in English | MEDLINE | ID: covidwho-2061811

ABSTRACT

Co-infections between SARS-CoV-2 and other pathogens is an important consideration for the treatment of patients with COVID-19. Aspergillus infections are part of this consideration since they present high morbidity and mortality. We present the case of a patient with COVID-19 and Aspergillus Fumigatus coinfection that evolves with brain death due to multiple heterogeneous lesions in the brain, which after a post-mortem biopsy found pathological lesions compatible with Aspergillus.


Subject(s)
COVID-19 , Neuroaspergillosis , Humans , Neuroaspergillosis/pathology , Neuroaspergillosis/therapy , COVID-19/complications , Brain Death , SARS-CoV-2 , Aspergillus fumigatus
4.
Front Immunol ; 13: 954985, 2022.
Article in English | MEDLINE | ID: covidwho-2022738

ABSTRACT

Patients suffering from coronavirus disease-2019 (COVID-19) are susceptible to deadly secondary fungal infections such as COVID-19-associated pulmonary aspergillosis and COVID-19-associated mucormycosis. Despite this clinical observation, direct experimental evidence for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)-driven alterations of antifungal immunity is scarce. Using an ex-vivo whole blood stimulation assay, we challenged blood from twelve COVID-19 patients with Aspergillus fumigatus and Rhizopus arrhizus antigens and studied the expression of activation, maturation, and exhaustion markers, as well as cytokine secretion. Compared to healthy controls, T-helper cells from COVID-19 patients displayed increased expression levels of the exhaustion marker PD-1 and weakened A. fumigatus- and R. arrhizus-induced activation. While baseline secretion of proinflammatory cytokines was massively elevated, whole blood from COVID-19 patients elicited diminished release of T-cellular (e.g., IFN-γ, IL-2) and innate immune cell-derived (e.g., CXCL9, CXCL10) cytokines in response to A. fumigatus and R. arrhizus antigens. Additionally, samples from COVID-19 patients showed deficient granulocyte activation by mold antigens and reduced fungal killing capacity of neutrophils. These features of weakened anti-mold immune responses were largely decoupled from COVID-19 severity, the time elapsed since diagnosis of COVID-19, and recent corticosteroid uptake, suggesting that impaired anti-mold defense is a common denominator of the underlying SARS-CoV-2 infection. Taken together, these results expand our understanding of the immune predisposition to post-viral mold infections and could inform future studies of immunotherapeutic strategies to prevent and treat fungal superinfections in COVID-19 patients.


Subject(s)
COVID-19 , Adrenal Cortex Hormones/therapeutic use , Aspergillus fumigatus , Cytokines/metabolism , Humans , SARS-CoV-2
5.
Intern Med J ; 51 Suppl 7: 143-176, 2021 11.
Article in English | MEDLINE | ID: covidwho-1961593

ABSTRACT

Invasive aspergillosis (IA) in haematology/oncology patients presents as primary infection or breakthrough infection, which can become refractory to antifungal treatment and has a high associated mortality. Other emerging patient risk groups include patients in the intensive care setting with severe respiratory viral infections, including COVID-19. These guidelines present key diagnostic and treatment recommendations in light of advances in knowledge since the previous guidelines in 2014. Culture and histological-based methods remain central to the diagnosis of IA. There is increasing evidence for the utility of non-culture methods employing fungal biomarkers in pre-emptive screening for infection, as well as for IA diagnosis when used in combination. Although azole resistance appears to be uncommon in Australia, susceptibility testing of clinical Aspergillus fumigatus complex isolates is recommended. Voriconazole remains the preferred first-line antifungal agent for treating primary IA, including for extrapulmonary disease. Recommendations for paediatric treatment broadly follow those for adults. For breakthrough and refractory IA, a change in class of antifungal agent is strongly recommended, and agents under clinical trial may need to be considered. Newer immunological-based imaging modalities warrant further study, while surveillance for IA and antifungal resistance remain essential to informing the relevance of current treatment recommendations.


Subject(s)
Aspergillosis , COVID-19 , Adult , Antifungal Agents/therapeutic use , Aspergillosis/diagnosis , Aspergillosis/drug therapy , Aspergillus fumigatus , Child , Drug Resistance, Fungal , Humans , SARS-CoV-2 , Voriconazole/therapeutic use
7.
Med Mycol ; 60(5)2022 May 28.
Article in English | MEDLINE | ID: covidwho-1860885

ABSTRACT

Although a high prevalence of COVID-19-associated pulmonary aspergillosis has been reported, it is still difficult to distinguish between colonization with Aspergillus fumigatus and infection. Concomitantly, similarities between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and hypersensitivity pneumonitis were suggested. The objective of this study was to investigate retrospectively if precipitin assays targeting A. fumigatus could have been useful in the management of SARS-CoV-2 patients hospitalized in an Intensive Care Unit (ICU) in 2020. SARS-CoV-2 ICU patients were screened for Aspergillus co-infection using biomarkers (galactomannan antigen, qPCR) and culture of respiratory samples (tracheal aspirates and bronchoalveolar lavage). For all these patients, clinical data, ICU characteristics and microbial results were collected. Electrosyneresis assays were performed using commercial A. fumigatus somatic and metabolic antigens. ELISA were performed using in-house A. fumigatus purified antigen and recombinant antigens.Our study population consisted of 65 predominantly male patients, with a median ICU stay of 22 days, and a global survival rate of 62%. Thirty-five patients had at least one positive marker for Aspergillus species detection. The number of arcs obtained by electrosyneresis using the somatic A. fumigatus antigen was significantly higher for these 35 SARS-CoV-2 ICU patients (P 0.01, Welch's t-test). Our study showed that SARS-CoV-2 ICU patients with a positive marker for Aspergillus species detection more often presented precipitins towards A. fumigatus. Serology assays could be an additional tool to assess the clinical relevance of the Aspergillus species in respiratory samples of SARS-CoV-2 ICU patients. LAY SUMMARY: This study showed retrospectively that precipitin assays, such as electrosyneresis, could be helpful to distinguish between colonization and infection with Aspergillus fumigatus during the management of severe acute respiratory syndrome Coronavirus-2 (SARS CoV-2) patients in an intensive care unit.


Subject(s)
COVID-19 , Invasive Pulmonary Aspergillosis , Animals , Antigens, Fungal , Aspergillus , Aspergillus fumigatus , Biomarkers , COVID-19/diagnosis , COVID-19/veterinary , Female , Invasive Pulmonary Aspergillosis/diagnosis , Invasive Pulmonary Aspergillosis/veterinary , Male , Precipitins , Retrospective Studies , SARS-CoV-2
8.
Nat Commun ; 13(1): 1926, 2022 04 08.
Article in English | MEDLINE | ID: covidwho-1839522

ABSTRACT

Invasive aspergillosis is a critical complication in immunocompromised patients with hematologic malignancies or with viral pneumonia caused by influenza virus or SARS­CoV­2. Although early and accurate diagnosis of invasive aspergillosis can maximize clinical outcomes, current diagnostic methods are time-consuming and poorly sensitive. Here, we assess the ability of 2-deoxy-2-18F-fluorosorbitol (18F-FDS) positron emission tomography (PET) to specifically and noninvasively detect Aspergillus infections. We show that 18F-FDS PET can be used to visualize Aspergillus fumigatus infection of the lungs, brain, and muscles in mouse models. In particular, 18F-FDS can distinguish pulmonary aspergillosis from Staphylococcus aureus infection, both of which induce pulmonary infiltrates in immunocompromised patients. Thus, our results indicate that the combination of 18F-FDS PET and appropriate clinical information may be useful in the differential diagnosis and localization of invasive aspergillosis.


Subject(s)
Aspergillosis , COVID-19 , Invasive Fungal Infections , Animals , Aspergillosis/diagnostic imaging , Aspergillus fumigatus , Humans , Lung/diagnostic imaging , Mice , Positron-Emission Tomography/methods , SARS-CoV-2
9.
Mar Drugs ; 20(3)2022 Feb 24.
Article in English | MEDLINE | ID: covidwho-1725847

ABSTRACT

The COVID-19 pandemic and its continuing emerging variants emphasize the need to discover appropriate treatment, where vaccines alone have failed to show complete protection against the new variants of the virus. Therefore, treatment of the infected cases is critical. This paper discusses the bio-guided isolation of three indole diketopiperazine alkaloids, neoechinulin A (1), echinulin (2), and eurocristatine (3), from the Red Sea-derived Aspergillus fumigatus MR2012. Neoechinulin A (1) exhibited a potent inhibitory effect against SARS-CoV-2 Mpro with IC50 value of 0.47 µM, which is comparable to the reference standard GC376. Despite the structural similarity between the three compounds, only 1 showed a promising effect. The mechanism of inhibition is discussed in light of a series of extensive molecular docking, classical and steered molecular dynamics simulation experiments. This paper sheds light on indole diketopiperazine alkaloids as a potential structural motif against SARS-CoV-2 Mpro. Additionally, it highlights the potential of different molecular docking and molecular dynamics simulation approaches in the discrimination between active and inactive structurally related Mpro inhibitors.


Subject(s)
Antiviral Agents/chemistry , Coronavirus 3C Proteases/antagonists & inhibitors , Cysteine Proteinase Inhibitors/chemistry , Indole Alkaloids/chemistry , Piperazines/chemistry , SARS-CoV-2/enzymology , Alkaloids/chemistry , Alkaloids/isolation & purification , Antiviral Agents/isolation & purification , Aspergillus fumigatus/chemistry , Cysteine Proteinase Inhibitors/isolation & purification , Indole Alkaloids/isolation & purification , Molecular Docking Simulation , Molecular Dynamics Simulation , Piperazines/isolation & purification
10.
Mycoses ; 65(3): 362-373, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1700157

ABSTRACT

OBJECTIVES: (1) To describe the incidence, clinical characteristics, treatment and outcome of Aspergillus Endocarditis (AE) in a nationwide multicentric cohort (GAMES). (2) To compare the AE cases of the GAMES cohort, with the AE cases reported in the literature since 2010. (3) To identify variables related to mortality. METHODS: We recruited 10 AE cases included in the GAMES cohort (January 2008-December 2018) and 51 cases from the literature published from January 2010 to July 2019. RESULTS: 4528 patients with infectious endocarditis (IE) were included in the GAMES cohort, of them 10 (0.2%) were AE. After comparing our 10 cases with the 51 of the literature, no differences were found. Analysing the 61 AE cases together, 55.7% were male, median age 45 years. Their main underlying conditions were as follows: prosthetic valve surgery (34.4%) and solid organ transplant (SOT) (19.7%). Mainly affecting mitral (36.1%) and aortic valve (29.5%). Main isolated species were as follows: Aspergillus fumigatus (47.5%) and Aspergillus flavus (24.6%). Embolisms occurred in 54%. Patients were treated with antifungals (90.2%), heart surgery (85.2%) or both (78.7%). Overall, 52.5% died. A greater mortality was observed in immunosuppressed patients (59.4% vs. 24.1%, OR = 4.09, 95%CI = 1.26-13.19, p = .02), and lower mortality was associated with undergoing cardiac surgery plus azole therapy (28.1% vs. 65.5%, OR = 0.22, 95%CI = 0.07-0.72, p = .01). CONCLUSIONS: AE accounts for 0.2% of all IE episodes of a national multicentric cohort, mainly affecting patients with previous valvular surgery or SOT recipients. Mortality remains high especially in immunosuppressed hosts and azole-based treatment combined with surgical resection are related to a better outcome.


Subject(s)
Aspergillosis , Endocarditis , Antifungal Agents/therapeutic use , Aspergillosis/drug therapy , Aspergillus , Aspergillus fumigatus , Endocarditis/drug therapy , Endocarditis/therapy , Humans , Male , Middle Aged
11.
Mycoses ; 65(4): 458-465, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1691477

ABSTRACT

BACKGROUND: COVID-19-associated invasive pulmonary aspergillosis (CAPA) is associated with increased mortality. Cases of CAPA caused by azole-resistant Aspergillus fumigatus strains have been reported. OBJECTIVES: To analyse the twelve-month CAPA prevalence in a German tertiary care hospital and to characterise clinical A. fumigatus isolates from two German hospitals by antifungal susceptibility testing and microsatellite genotyping. PATIENTS/METHODS: Retrospective observational study in critically ill adults from intensive care units with COVID-19 from 17 February 2020 until 16 February 2021 and collection of A. fumigatus isolates from two German centres. EUCAST broth microdilution for four azole compounds and microsatellite PCR with nine markers were performed for each collected isolate (N = 27) and additional for three non-COVID A. fumigatus isolates. RESULTS: welve-month CAPA prevalence was 7.2% (30/414), and the rate of azole-resistant A. fumigatus isolates from patients with CAPA was 3.7% with detection of one TR34/L98H mutation. The microsatellite analysis revealed no major clustering of the isolates. Sequential isolates mainly showed the same genotype over time. CONCLUSIONS: Our findings demonstrate similar CAPA prevalence to other reports and a low azole-resistance rate. Genotyping of A. fumigatus showed polyclonal distribution except for sequential isolates.


Subject(s)
COVID-19 , Pulmonary Aspergillosis , Adult , Antifungal Agents/pharmacology , Aspergillus fumigatus , Azoles/pharmacology , Drug Resistance, Fungal/genetics , Fungal Proteins/genetics , Humans , Intensive Care Units , Microbial Sensitivity Tests , Pulmonary Aspergillosis/complications , Pulmonary Aspergillosis/epidemiology
12.
mSphere ; 7(1): e0094021, 2022 02 23.
Article in English | MEDLINE | ID: covidwho-1662305

ABSTRACT

Fungal infections remain a major global concern. Emerging fungal pathogens and increasing rates of resistance mean that additional research efforts and resources must be allocated to advancing our understanding of fungal pathogenesis and developing new therapeutic interventions. Neutrophilic granulocytes are a major cell type involved in protection against the important fungal pathogen Aspergillus fumigatus, where they employ numerous defense mechanisms, including production of antimicrobial extracellular vesicles. A major drawback to work with neutrophils is the lack of a suitable cell line system for the study of fungal pathogenesis. To address this problem, we assessed the feasibility of using differentiated PLB-985 neutrophil-like cells as an in vitro model to study A. fumigatus infection. We find that dimethylformamide-differentiated PLB-985 cells provide a useful recapitulation of many aspects of A. fumigatus interactions with primary human polymorphonuclear leukocytes. We show that differentiated PLB-985 cells phagocytose fungal conidia and acidify conidia-containing phagolysosomes similar to primary neutrophils, release neutrophil extracellular traps, and also produce antifungal extracellular vesicles in response to infection. In addition, we provide an improved method for the isolation of extracellular vesicles produced during infection by employing a size exclusion chromatography-based approach. Advanced liquid chromatography-tandem mass spectrometry (LC-MS/MS) proteomics revealed an enrichment of extracellular vesicle marker proteins and a decrease of cytoplasmic proteins in extracellular vesicles isolated using this improved method. Ultimately, we find that differentiated PLB-985 cells can serve as a genetically tractable model to study many aspects of A. fumigatus pathogenesis. IMPORTANCE Polymorphonuclear leukocytes are an important defense against human fungal pathogens, yet our model systems to study this group of cells remain very limited in scope. In this study, we established that differentiated PLB-985 cells can serve as a model to recapitulate several important aspects of human polymorphonuclear leukocyte interactions with the important human fungal pathogen Aspergillus fumigatus. The proposed addition of a cultured neutrophil-like cell line to the experimental toolbox to study fungal pathogenesis will allow for a more mechanistic description of neutrophil antifungal biology. In addition, the easier handling of the cell line compared to primary human neutrophils allowed us to use PLB-985 cells to provide an improved method for isolation of neutrophil-derived extracellular vesicles using size exclusion chromatography. Together, these results provide significant tools and a baseline knowledge for the future study of neutrophil-derived extracellular vesicles in the laboratory.


Subject(s)
Aspergillus fumigatus , Neutrophils , Antifungal Agents , Aspergillus fumigatus/physiology , Chromatography, Liquid , Humans , Neutrophils/microbiology , Tandem Mass Spectrometry
13.
Mycopathologia ; 186(5): 589-608, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1653639

ABSTRACT

Respiratory infections caused by fungal pathogens present a growing global health concern and are a major cause of death in immunocompromised patients. Worryingly, coronavirus disease-19 (COVID-19) resulting in acute respiratory distress syndrome has been shown to predispose some patients to airborne fungal co-infections. These include secondary pulmonary aspergillosis and mucormycosis. Aspergillosis is most commonly caused by the fungal pathogen Aspergillus fumigatus and primarily treated using the triazole drug group, however in recent years, this fungus has been rapidly gaining resistance against these antifungals. This is of serious clinical concern as multi-azole resistant forms of aspergillosis have a higher risk of mortality when compared against azole-susceptible infections. With the increasing numbers of COVID-19 and other classes of immunocompromised patients, early diagnosis of fungal infections is critical to ensuring patient survival. However, time-limited diagnosis is difficult to achieve with current culture-based methods. Advances within fungal genomics have enabled molecular diagnostic methods to become a fast, reproducible, and cost-effective alternative for diagnosis of respiratory fungal pathogens and detection of antifungal resistance. Here, we describe what techniques are currently available within molecular diagnostics, how they work and when they have been used.


Subject(s)
COVID-19 , Pulmonary Medicine , Aspergillus fumigatus , Genomics , Humans , SARS-CoV-2
14.
J Investig Med High Impact Case Rep ; 10: 23247096211063332, 2022.
Article in English | MEDLINE | ID: covidwho-1603889

ABSTRACT

We present the case of a 56-year-old woman who was diagnosed with severe coronavirus disease 2019 (COVID-19) pneumonia complicated by severe acute respiratory distress syndrome who was intubated for 19 days. She recovered from COVID-19 after a month. A computed tomography (CT) scan of the chest, after a month, showed improved infiltrates with a small residual cavity within the lingula. A CT angiogram showed a more confluent density in the lingular portion on follow-up 2 months later. She developed intermittent hemoptysis after 3 months in December 2020, which persisted for almost 6 months, and CT of the chest showed the lingular nodular with resolution of the cavitation. She underwent bronchoscopy with bronchoalveolar lavage, confirming Aspergillus fumigatus by galactomannan assay and histology showing branching hyphae. Once she started treatment with itraconazole, her hemoptysis resolved. The follow-up CT of the chest after 2 months of treatment did not show a cavity or a nodule in the lingula. Our patient developed invasive pulmonary aspergillosis (IPA) as a sequela of severe COVID-19 infection. COVID-19-associated invasive pulmonary aspergillosis (CAPA) is an underrecognized complication that needs to be investigated on whether prophylactic treatment is required. Our case also demonstrates that the diagnosis of IPA needs to be considered months after COVID-19 infection when a superimposed fungal infection can occur after a viral infection if the patient continues to have persistent symptoms.


Subject(s)
COVID-19 , Invasive Pulmonary Aspergillosis , Pulmonary Aspergillosis , Aspergillus fumigatus , Female , Humans , Invasive Pulmonary Aspergillosis/complications , Invasive Pulmonary Aspergillosis/diagnosis , Invasive Pulmonary Aspergillosis/drug therapy , Middle Aged , Pulmonary Aspergillosis/complications , Pulmonary Aspergillosis/drug therapy , SARS-CoV-2
15.
Anal Biochem ; 632: 114384, 2021 11 01.
Article in English | MEDLINE | ID: covidwho-1415148

ABSTRACT

Invasive pulmonary aspergillosis (IPA) is a severe life-threatening condition. Diagnosis of fungal disease in general, and especially that caused by Aspergillus fumigatus is problematic. A. fumigatus secretes siderophores to acquire iron during infection, which are also essential for virulence. We describe the chemoacetylation of ferrated fusarinine C to diacetylated fusarinine C (DAFC), followed by protein conjugation, which facilitated triacetylfusarinine C (TAFC)-specific monoclonal antibody production with specific recognition of the ferrated form of TAFC. A single monoclonal antibody sequence was ultimately elucidated by a combinatorial strategy involving protein LC-MS/MS, cDNA sequencing and RNAseq. The resultant murine IgG2a monoclonal antibody was secreted in, and purified from, mammalian cell culture (5 mg) and demonstrated to be highly specific for TAFC detection by competitive ELISA (detection limit: 15 nM) and in a lateral flow test system (detection limit: 3 ng), using gold nanoparticle conjugated- DAFC-bovine serum albumin for competition. Overall, this work reveals for the first time a recombinant TAFC-specific monoclonal antibody with diagnostic potential for IPA diagnosis in traditional and emerging patient groups (e.g., COVID-19) and presents a useful strategy for murine Ig sequence determination, and expression in HEK293 cells, to overcome unexpected limitations associated with aberrant or deficient murine monoclonal antibody production.


Subject(s)
Antibodies, Monoclonal/immunology , Aspergillosis/diagnosis , Ferric Compounds/immunology , Hydroxamic Acids/immunology , Immunoconjugates/chemistry , Siderophores/chemistry , Animals , Aspergillosis/microbiology , Aspergillus fumigatus/chemistry , Aspergillus fumigatus/pathogenicity , Enzyme-Linked Immunosorbent Assay , Ferric Compounds/analysis , HEK293 Cells , Humans , Hydroxamic Acids/analysis , Mice , Recombinant Proteins/immunology
16.
17.
PLoS Pathog ; 17(7): e1009711, 2021 07.
Article in English | MEDLINE | ID: covidwho-1360655

ABSTRACT

Aspergillus fumigatus is an opportunistic human pathogen that causes aspergillosis, a spectrum of environmentally acquired respiratory illnesses. It has a cosmopolitan distribution and exists in the environment as a saprotroph on decaying plant matter. Azoles, which target Cyp51A in the ergosterol synthesis pathway, are the primary class of drugs used to treat aspergillosis. Azoles are also used to combat plant pathogenic fungi. Recently, an increasing number of azole-naive patients have presented with pan-azole-resistant strains of A. fumigatus. The TR34/L98H and TR46/Y121F/T289A alleles in the cyp51A gene are the most common ones conferring pan-azole resistance. There is evidence that these mutations arose in agricultural settings; therefore, numerous studies have been conducted to identify azole resistance in environmental A. fumigatus and to determine where resistance is developing in the environment. Here, we summarize the global occurrence of azole-resistant A. fumigatus in the environment based on available literature. Additionally, we have created an interactive world map showing where resistant isolates have been detected and include information on the specific alleles identified, environmental settings, and azole fungicide use. Azole-resistant A. fumigatus has been found on every continent, except for Antarctica, with the highest number of reports from Europe. Developed environments, specifically hospitals and gardens, were the most common settings where azole-resistant A. fumigatus was detected, followed by soils sampled from agricultural settings. The TR34/L98H resistance allele was the most common in all regions except South America where the TR46/Y121F/T289A allele was the most common. A major consideration in interpreting this survey of the literature is sampling bias; regions and environments that have been extensively sampled are more likely to show greater azole resistance even though resistance could be more prevalent in areas that are under-sampled or not sampled at all. Increased surveillance to pinpoint reservoirs, as well as antifungal stewardship, is needed to preserve this class of antifungals for crop protection and human health.


Subject(s)
Aspergillosis/microbiology , Aspergillus fumigatus/genetics , Drug Resistance, Fungal/genetics , Animals , Antifungal Agents , Azoles , Disease Reservoirs , Humans
18.
mBio ; 12(4): e0180321, 2021 08 31.
Article in English | MEDLINE | ID: covidwho-1350005

ABSTRACT

Azole resistance in pathogenic Aspergillus fumigatus has become a global public health issue threatening the use of medical azoles. The environmentally occurring resistance mutations, TR34/L98H (TR34) and TR46/Y121F/T289A (TR46), are widespread across multiple continents and emerging in the United States. We used whole-genome single nucleotide polymorphism (SNP) analysis on 179 nationally represented clinical and environmental A. fumigatus genomes from the United States along with 18 non-U.S. genomes to evaluate the genetic diversity and foundation of the emergence of azole resistance in the United States. We demonstrated the presence of clades of A. fumigatus isolates: clade A (17%) comprised a global collection of clinical and environmental azole-resistant strains, including all strains with the TR34/L98H allele from India, The Netherlands, the United Kingdom, and the United States, and clade B (83%) consisted of isolates without this marker mainly from the United States. The TR34/L98H polymorphism was shared among azole-resistant A. fumigatus strains from India, The Netherlands, the United Kingdom, and the United States, suggesting the common origin of this resistance mechanism. Six percent of azole-resistant A. fumigatus isolates from the United States with the TR34 resistance marker had a mixture of clade A and clade B alleles, suggestive of recombination. Additionally, the presence of equal proportions of both mating types further suggests the ongoing presence of recombination. This study demonstrates the genetic background for the emergence of azole resistance in the United States, supporting a single introduction and subsequent propagation, possibly through recombination of environmentally driven resistance mutations. IMPORTANCE Aspergillus fumigatus is one of the most common causes of invasive mold infections in patients with immune deficiencies and has also been reported in patients with severe influenza and severe acute respiratory syndrome coronavirus 2 (SARs-CoV-2). Triazole drugs are the first line of therapy for this infection; however, their efficacy has been compromised by the emergence of azole resistance in A. fumigatus, which was proposed to be selected for by exposure to azole fungicides in the environment [P. E. Verweij, E. Snelders, G. H. J. Kema, E. Mellado, et al., Lancet Infect Dis 9:789-795, 2009, https://doi.org/10.1016/S1473-3099(09)70265-8]. Isolates with environmentally driven resistance mutations, TR34/L98H (TR34) and TR46/Y121F/T289A (TR46), have been reported worldwide. Here, we used genomic analysis of a large sample of resistant and susceptible A. fumigatus isolates to demonstrate a single introduction of TR34 in the United States and suggest its ability to spread into the susceptible population is through recombination between resistant and susceptible isolates.


Subject(s)
Antifungal Agents/pharmacology , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/genetics , Drug Resistance, Fungal/genetics , Triazoles/pharmacology , Aspergillosis/drug therapy , Aspergillus fumigatus/isolation & purification , Cytochrome P-450 Enzyme System/genetics , Fungal Proteins/genetics , Genome, Fungal/genetics , Humans , Microbial Sensitivity Tests , Polymorphism, Single Nucleotide/genetics , United States , Whole Genome Sequencing
19.
Cell Host Microbe ; 29(8): 1277-1293.e6, 2021 Aug 11.
Article in English | MEDLINE | ID: covidwho-1293647

ABSTRACT

Immune deactivation of phagocytes is a central event in the pathogenesis of sepsis. Herein, we identify a master regulatory role of IL-6 signaling on LC3-associated phagocytosis (LAP) and reveal that uncoupling of these two processes during sepsis induces immunoparalysis in monocytes/macrophages. In particular, we demonstrate that activation of LAP by the human fungal pathogen Aspergillus fumigatus depends on ERK1/2-mediated phosphorylation of p47phox subunit of NADPH oxidase. Physiologically, autocrine IL-6/JAK2/Ninein axis orchestrates microtubule organization and dynamics regulating ERK recruitment to the phagosome and LC3+ phagosome (LAPosome) formation. In sepsis, loss of IL-6 signaling specifically abrogates microtubule-mediated trafficking of ERK, leading to defective activation of LAP and impaired killing of bacterial and fungal pathogens by monocytes/macrophages, which can be selectively restored by IL-6 supplementation. Our work uncovers a molecular pathway linking IL-6 signaling with LAP and provides insight into the mechanisms underlying immunoparalysis in sepsis.


Subject(s)
Interleukin-6/metabolism , Microtubule-Associated Proteins/metabolism , Phagocytosis/immunology , Signal Transduction , Aspergillus fumigatus/metabolism , Cytokines/metabolism , Cytoskeletal Proteins/metabolism , Humans , Janus Kinase 2/metabolism , Macrophages , Monocytes , Nuclear Proteins/metabolism , Phagocytes , Phagocytosis/physiology , Sepsis/metabolism
20.
Microbiol Spectr ; 9(1): e0001021, 2021 09 03.
Article in English | MEDLINE | ID: covidwho-1262384

ABSTRACT

The ongoing global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for coronavirus disease 2019 (COVID-19), first described in Wuhan, China. A subset of COVID-19 patients has been reported to have acquired secondary infections by microbial pathogens, such as opportunistic fungal pathogens from the genus Aspergillus. To gain insight into COVID-19-associated pulmonary aspergillosis (CAPA), we analyzed the genomes and characterized the phenotypic profiles of four CAPA isolates of Aspergillus fumigatus obtained from patients treated in the area of North Rhine-Westphalia, Germany. By examining the mutational spectrum of single nucleotide polymorphisms, insertion-deletion polymorphisms, and copy number variants among 206 genes known to modulate A. fumigatus virulence, we found that CAPA isolate genomes do not exhibit significant differences from the genome of the Af293 reference strain. By examining a number of factors, including virulence in an invertebrate moth model, growth in the presence of osmotic, cell wall, and oxidative stressors, secondary metabolite biosynthesis, and the MIC of antifungal drugs, we found that CAPA isolates were generally, but not always, similar to A. fumigatus reference strains Af293 and CEA17. Notably, CAPA isolate D had more putative loss-of-function mutations in genes known to increase virulence when deleted. Moreover, CAPA isolate D was significantly more virulent than the other three CAPA isolates and the A. fumigatus reference strains Af293 and CEA17, but similarly virulent to two other clinical strains of A. fumigatus. These findings expand our understanding of the genomic and phenotypic characteristics of isolates that cause CAPA. IMPORTANCE The global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of coronavirus disease 2019 (COVID-19), has already killed millions of people. COVID-19 patient outcome can be further complicated by secondary infections, such as COVID-19-associated pulmonary aspergillosis (CAPA). CAPA is caused by Aspergillus fungal pathogens, but there is little information about the genomic and phenotypic characteristics of CAPA isolates. We conducted genome sequencing and extensive phenotyping of four CAPA isolates of Aspergillus fumigatus from Germany. We found that CAPA isolates were often, but not always, similar to other reference strains of A. fumigatus across 206 genetic determinants of infection-relevant phenotypes, including virulence. For example, CAPA isolate D was more virulent than other CAPA isolates and reference strains in an invertebrate model of fungal disease, but similarly virulent to two other clinical strains. These results expand our understanding of COVID-19-associated pulmonary aspergillosis.


Subject(s)
Aspergillus fumigatus/genetics , COVID-19/complications , Genomics , Phenotype , Pulmonary Aspergillosis/complications , Aged , Antifungal Agents , Aspergillus , Aspergillus fumigatus/classification , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/isolation & purification , Female , Humans , Male , Metabolomics , Microbial Sensitivity Tests , Middle Aged , Mutation , Polymorphism, Single Nucleotide , SARS-CoV-2 , Secondary Metabolism/genetics , Virulence/genetics
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