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1.
Viruses ; 15(9)2023 08 25.
Article in English | MEDLINE | ID: mdl-37766216

ABSTRACT

After the acute phase of COVID-19, some patients develop long COVID. This term is used for a variety of conditions with a complex, yet not fully elucidated etiology, likely including the prolonged persistence of the virus in the organism and progression to lung fibrosis. We present a unique autopsy case of a patient with severe COVID-19 with prolonged viral persistence who developed interstitial lung fibrosis complicated by a fatal combination of cytomegalovirus and Aspergillus infection. SARS-CoV-2 virus was detected at autopsy in the lungs more than two months after the acute infection, although tests from the nasopharynx were negative. Immune dysregulation after COVID-19 and the administration of corticoid therapy created favorable conditions for the cytomegalovirus and Aspergillus infection that were uncovered at autopsy. These pathogens may represent a risk for opportunistic infections, complicating not only the acute coronavirus infection but also long COVID, as was documented in the presented case.


Subject(s)
Aspergillosis , COVID-19 , Pulmonary Fibrosis , Humans , COVID-19/complications , COVID-19/pathology , Cytomegalovirus , Post-Acute COVID-19 Syndrome , SARS-CoV-2 , Pulmonary Fibrosis/pathology , Autopsy , Lung/pathology , Aspergillosis/pathology
2.
Ann Pathol ; 43(6): 525-526, 2023 Nov.
Article in French | MEDLINE | ID: mdl-37407416

ABSTRACT

A 31-year-old man, with no past medical history, presented with headaches, sudden loss of vision, right exophtalmia, bilateral papilledema, and fever. Brain imaging noted a right basi-temporal lesion. Excision of the lesion was performed. The histological examination noted a glial tissue with acute inflammatory changes and multinucleated giant cells. Within this infiltrate there were septate and branched hyphae consistent with aspergillosis. These filaments were stained with PAS. The patient died post-operatively.


Subject(s)
Aspergillosis , Papilledema , Male , Humans , Adult , Aspergillosis/complications , Aspergillosis/diagnosis , Aspergillosis/pathology , Brain/diagnostic imaging , Brain/pathology , Headache/etiology
3.
Pneumologie ; 77(9): 639-644, 2023 Sep.
Article in English | MEDLINE | ID: mdl-38452864

ABSTRACT

We report a patient with severe cavitary pulmonary tuberculosis and Aspergillus niger superinfection, whose only comorbidity was untreated diabetes mellitus. A. niger pneumonia was proven by PCR, sequencing and culture of pleural and respiratory secretions. The patient was successfully treated with a four-drug antituberculous regimen, liposomal amphotericin B (up to 5 mg/kg/d) and pleuro-pneumonectomy. Histology of the resected lung revealed destroyed lung tissue with inflammatory cells and fungal conidia. There were large deposits of polarising material, which was found to be calcium oxalate. There was also nodular caseating necrosis bordered by epitheloid cells and connective tissue. Thus, all diagnostic criteria for invasive A. niger infection were met. Several local risk factors, such as extensive lung damage and tissue acidification, may have favoured superinfection by A. niger. This case highlights the diagnostic value of calcium oxalate crystals in lung tissue and the need for combined antimicrobial and surgical treatment in extensive invasive aspergillosis caused by A. niger.


Subject(s)
Aspergillosis , Aspergillus , Lung Diseases, Fungal , Pneumonia , Superinfection , Tuberculosis, Pulmonary , Humans , Aspergillus niger , Calcium Oxalate/analysis , Superinfection/diagnosis , Superinfection/complications , Lung Diseases, Fungal/complications , Lung Diseases, Fungal/diagnosis , Lung Diseases, Fungal/microbiology , Aspergillosis/diagnosis , Aspergillosis/microbiology , Aspergillosis/pathology , Pneumonia/complications , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/drug therapy
4.
mBio ; 13(5): e0225422, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36040029

ABSTRACT

Exposure of immunosuppressed individuals to the opportunistic fungal pathogen Aspergillus fumigatus may result in invasive pulmonary aspergillosis (IPA), which can lead to the development of cerebral aspergillosis (CA), a highly lethal infection localized in the central nervous system (CNS). There are no experimental models of CA that effectively mimic human disease, resulting in a considerable knowledge gap regarding mechanisms of neurological pathogenicity and neuroimmune responses during infection. In this report, immunosuppressed mice (via acute, high-dose corticosteroid administration) challenged with A. fumigatus resting conidia intranasally, followed a day later by a 70-fold lower inoculum of pre-swollen conidia intravenously (IN + IV + steroid), demonstrated increased weight loss, signs of severe clinical disease, increased fungal burden in the brain, and significant reduction in survival compared to immunosuppressed mice challenged intranasally only (IN + steroid) or non-immunosuppressed mice challenged both intranasally and intravenously (IN + IV). The IN + IV + steroid group demonstrated significant decreases in monocytes, eosinophils, dendritic cells (DCs), and invasive natural killer T (iNKT) cells, but not neutrophils or γδ T cells, in the brain compared to the IN + IV group. Likewise, the IN + IV + steroid group had significantly lower levels of interleukin (IL)-1ß, IL-6, IL-17A, CC motif chemokine ligand 3 (CCL3), CXC chemokine ligand 10 (CXCL10), and vascular endothelial growth factor (VEGF) in the brain compared to the IN + IV group. IN + IV + steroid was superior to both IN + IV + chemotherapy (cytarabine + daunorubicin) and IN + IV + neutropenia for the development of CA. In conclusion, we have developed a well-defined, physiologically relevant model of disseminated CA in corticosteroid-induced immunosuppressed mice with a primary pulmonary infection. This model will serve to advance understanding of disease mechanisms, identify immunopathogenic processes, and help define the protective neuroinflammatory response to CA. IMPORTANCE Invasive fungal infections (IFIs) result in significant mortality in immunosuppressed individuals. Of these, invasive pulmonary aspergillosis (IPA), caused by the opportunistic mold Aspergillus fumigatus, is the most lethal. Lethality in IPA is due to two main factors: destruction of the lung leading to compromised pulmonary function, and dissemination of the organism to extrapulmonary organs. Of these, the CNS is the most common site of dissemination. However, very little is known regarding the pathogenesis of or immune response during cerebral aspergillosis, which is directly due to the lack of an animal model that incorporates immunosuppression, lung infection, and consistent dissemination to the CNS/brain. In this report, we have developed a new experimental animal model of CA which includes the above parameters and characterized the neuroimmune response. We further compared this disseminated CA model to two additional immunosuppressive strategies. Overall, this model of disseminated CA following IPA in an immunosuppressed host provides a novel platform for studying the efficacy of antifungal drugs and immunotherapies for improving disease outcomes.


Subject(s)
Aspergillosis , Invasive Pulmonary Aspergillosis , Pneumonia , Mice , Humans , Animals , Invasive Pulmonary Aspergillosis/microbiology , Interleukin-17 , Vascular Endothelial Growth Factor A , Antifungal Agents , Ligands , Interleukin-6 , Aspergillosis/pathology , Aspergillus fumigatus , Disease Models, Animal , Lung/pathology , Adrenal Cortex Hormones , Steroids , Chemokines, CXC , Cytarabine , Daunorubicin , Chemokines
5.
Front Cell Infect Microbiol ; 12: 907519, 2022.
Article in English | MEDLINE | ID: mdl-35982778

ABSTRACT

Damage to the lung epithelium is a unifying feature of disease caused by the saprophytic fungus Aspergillus fumigatus. However, the mechanistic basis and the regulatory control of such damage is poorly characterized. Previous studies have identified A. fumigatus mediated pathogenesis as occurring at early (≤ 16 hours) or late (>16 hours) phases of the fungal interaction with epithelial cells, and respectively involve direct contact with the host cell or the action of soluble factors produced by mature fungal hyphae. Both early and late phases of epithelial damage have been shown to be subject to genetic regulation by the pH-responsive transcription factor PacC. This study sought to determine whether other transcriptional regulators play a role in modulating epithelial damage. In particular, whether the early and late phases of epithelial damage are governed by same or distinct regulators. Furthermore, whether processes such as spore uptake and hyphal adhesion, that have previously been documented to promote epithelial damage, are governed by the same cohorts of epithelial regulators. Using 479 strains from the recently constructed library of A. fumigatus transcription factor null mutants, two high-throughput screens assessing epithelial cell detachment and epithelial cell lysis were conducted. A total of 17 transcription factor mutants were found to exhibit reproducible deficits in epithelial damage causation. Of these, 10 mutants were defective in causing early phase damage via epithelial detachment and 8 mutants were defective in causing late phase damage via epithelial lysis. Remarkably only one transcription factor, PacC, was required for causation of both phases of epithelial damage. The 17 mutants exhibited varied and often unique phenotypic profiles with respect to fitness, epithelial adhesion, cell wall defects, and rates of spore uptake by epithelial cells. Strikingly, 9 out of 10 mutants deficient in causing early phase damage also exhibited reduced rates of hyphal extension, and culture supernatants of 7 out of 8 mutants deficient in late phase damage were significantly less cytotoxic. Our study delivers the first high-level overview of A. fumigatus regulatory genes governing lung epithelial damage, suggesting highly coordinated genetic orchestration of host-damaging activities that govern epithelial damage in both space and time.


Subject(s)
Aspergillosis , Aspergillus fumigatus , Lung , Transcription Factors , Aspergillosis/pathology , Aspergillus fumigatus/genetics , Aspergillus fumigatus/metabolism , Cell Wall/metabolism , Epithelium/microbiology , Epithelium/pathology , Fungal Proteins/genetics , Fungal Proteins/metabolism , Humans , Hyphae/genetics , Hyphae/metabolism , Lung/microbiology , Lung/pathology , Transcription Factors/genetics , Transcription Factors/metabolism
6.
Am J Forensic Med Pathol ; 43(4): 380-384, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-35703209

ABSTRACT

ABSTRACT: Severe fungal infections caused by highly invasive fungi such as Aspergillus are not easy to diagnose and often have a poor prognosis. In these cases, the nonspecific symptoms may make clinical diagnosis challenging, and consequently, the autopsy and postmortem histological investigations acquire a crucial role. We report the case of a young man in good health who died of septic shock 3 weeks after having had a tongue piercing. Intravitam investigations did not identify the etiology of the rapidly fatal infectious condition. The autopsy revealed flaccid organs of uniformly diminished consistency with abscesses and granulomatous foci with central necrosis. Histological examination showed the presence of septate mycotic hyphae, with a dichotomous 45-degree bifurcation, typical for Aspergillus , in all the examined organs, including the tongue. The molecular identification confirmed the presence of Aspergillus fumigatus. The observed macroscopic framework and the laboratory findings made it possible to diagnose pseudomembranous invasive tracheobronchial aspergillosis and to attribute the death to fatal invasive disseminated aspergillosis. The consistency and concordance of all the findings in our possession led us to suspect the practice of piercing as the triggering cause of the man's pathology.


Subject(s)
Aspergillosis , Body Piercing , Humans , Body Piercing/adverse effects , Aspergillosis/diagnosis , Aspergillosis/microbiology , Aspergillosis/pathology , Aspergillus fumigatus
7.
Immunohorizons ; 6(1): 78-89, 2022 01 21.
Article in English | MEDLINE | ID: mdl-35064029

ABSTRACT

Aspergillus fumigatus is an opportunistic fungal pathogen that causes a wide spectrum of diseases in humans, including life-threatening invasive infections as well as several hypersensitivity respiratory disorders. Disease prevention is predicated on the host's ability to clear A. fumigatus from the lung while also limiting inflammation and preventing allergic responses. IL-27 is an important immunoregulatory cytokine, but its role during A. fumigatus infection remains poorly understood. In contrast to most infection settings demonstrating that IL-27 is anti-inflammatory, in this study we report that this cytokine plays a proinflammatory role in mice repeatedly infected with A. fumigatus We found that mice exposed to A. fumigatus had significantly enhanced secretion of IL-27 in their lungs. Genetic ablation of IL-27Rα in mice resulted in significantly higher fungal burdens in the lung during infection. The increased fungal growth in IL-27Rα-/- mice was associated with reduced secretion of IL-12, TNF-α, and IFN-γ, diminished T-bet expression, as well as a reduction in CD4+ T cells and their activation in the lung, demonstrating that IL-27 signaling promotes Th1 immune responses during repeated exposure to A. fumigatus In addition, infected IL-27Rα-/- mice displayed reduced accumulation of dendritic cells and exudate macrophages in their lungs, and these cells had a lower expression of MHC class II. Collectively, this study suggests that IL-27 drives type 1 immunity and is indispensable for inhibiting fungal growth in the lungs of mice repeatedly exposed to A. fumigatus, highlighting a protective role for this cytokine during fungal infection.


Subject(s)
Aspergillosis/immunology , Interleukins/metabolism , Lung/pathology , Th1 Cells/immunology , Animals , Aspergillosis/microbiology , Aspergillosis/pathology , Aspergillus fumigatus/immunology , Disease Models, Animal , Interleukins/genetics , Lung/immunology , Lung/microbiology , Lymphocyte Activation , Mice , Mice, Inbred C57BL , Mice, Knockout , Signal Transduction
8.
J Immunol ; 208(3): 732-744, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34996839

ABSTRACT

Eosinophils are potent innate effector cells associated mainly with type 2 immune responses elicited by helminths and allergens. Their activity needs to be tightly controlled to prevent severe inflammation and tissue damage. Eosinophil degranulation and secretion of inflammatory effector molecules, including cytokines, chemokines, and lipid mediators, can be regulated by activating and inhibitory receptors on the cell surface. In this study, we investigated the modulation of proliferation, apoptosis, gene expression, and cytokine/chemokine secretion from IL-33-activated Mus musculus eosinophils on cross-linking of the transmembrane receptor Sialic acid-binding Ig-like lectin F (Siglec-F). Siglec-F contains an ITIM plus an ITIM-like motif in its intracellular tail and is mainly regarded as an inhibitory and apoptosis-inducing receptor. In vitro costimulation of bone marrow-derived eosinophils with anti-Siglec-F and IL-33 compared with treatment with either alone led to enhanced STAT6 phosphorylation, stronger induction of hypoxia/glycolysis-related proinflammatory genes, and elevated secretion of type 2 cytokines (IL-4, IL-13) and chemokines (CCL3, CCL4) with only minor effects on proliferation and apoptosis. Using a competitive mixed bone marrow chimera approach with wild-type and Siglec-F-deficient eosinophils, we observed no evidence for Siglec-F-regulated inhibition of Aspergillus fumigatus-elicited lung eosinophilia. Truncation of the Siglec-F cytoplasmic tail, but not mutation of the ITIM and ITIM-like motifs, ablated the effect of enhanced cytokine/chemokine secretion. This provides evidence for an ITIM phosphorylation-independent signaling pathway from the cytoplasmic tail of the Siglec-F receptor that enhances effector molecule release from activated eosinophils.


Subject(s)
Aspergillosis/immunology , Eosinophilia/immunology , Eosinophils/immunology , Interleukin-33/metabolism , Sialic Acid Binding Immunoglobulin-like Lectins/metabolism , Animals , Apoptosis/immunology , Aspergillosis/pathology , Aspergillus fumigatus/immunology , Bone Marrow Cells/cytology , Bone Marrow Cells/metabolism , Cells, Cultured , Chemokine CCL3/metabolism , Chemokine CCL4/metabolism , Humans , Interleukin-13/metabolism , Interleukin-33/immunology , Interleukin-4/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Phosphorylation , STAT6 Transcription Factor/metabolism , Sialic Acid Binding Immunoglobulin-like Lectins/genetics
11.
Pan Afr Med J ; 42: 226, 2022.
Article in French | MEDLINE | ID: mdl-36845235

ABSTRACT

Sternal osteomyelitis due to aspergillosis is extremely rare. Among all cases of invasive aspergillosis reported in the literature, the incidence of osteomyelitis is less than 3%. Aspergillosis mainly affects immunosuppressed patients. Clinical and radiological manifestation is nonspecific. Contamination is primarily caused by inhaling spores, but it can also directly reach a vulnerable area after medical procedure. Diagnosis is often difficult and may take several weeks, in particular when aspergillosis is not suspected. Positive diagnosis is based on imaging tests but it is confirmed by anatomopathological and/or mycological examinations. Prognosis mainly depends on early administration of treatment. We here report the case of a 63-year-old diabetic patient with sternocostal osteomyelitis due to Aspergillus occurred after coronary angioplasty.


Subject(s)
Aspergillosis , Osteomyelitis , Humans , Middle Aged , Aspergillus , Aspergillosis/diagnosis , Aspergillosis/pathology , Immunocompromised Host , Osteomyelitis/therapy , Angioplasty
12.
Rev Assoc Med Bras (1992) ; 67(7): 1021-1025, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34817517

ABSTRACT

OBJECTIVE: Gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index are three systemic immune and inflammation indexes that were investigated for their diagnostic and prognostic proficiencies in cardiovascular diseases and cancers. However, their predictive values for invasive aspergillosis have not yet been studied. The aim of this study was to evaluate Gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index levels and their diagnostic values in invasive aspergillosis. METHODS: A total of 23 patients with invasive aspergillosis and 23 sex- and age-matched healthy participants were included in this study. Complete blood count parameters and liver function tests were studied. Gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index were calculated. RESULTS: Leukocyte, neutrophil, lymphocyte, and monocyte levels were statistically significantly higher in IA group (p=0.031, p=0.027, p=0.033, and p=0.001, respectively). In invasive aspergillosis group, platelets were numerically lower; Aspartate transaminase, alanine aminotransferase, and lactic dehydrogenase levels were numerically higher than those in control group but differences between levels were not statistically significant (p>0.05). The γ-glutamyl transpeptidase levels of patients were statistically significantly higher (p=0.007), and in addition, statistically significant differences were found between groups in terms of gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index (p<0.001, p=0.037, p=0.001, respectively). Receiver operating characteristic analysis was performed, and areas under the curves were evaluated. gamma-glutamyl transpeptidase-platelet ratio had the higher area under the curve than systemic immune inflammation index and system inflammation response index (AUC 0.849, 0.798, 0.693, respectively). The results from receiver operating characteristic analysis of the data suggested that the use of a cutoff value of 0.15 for gamma-glutamyl transpeptidase-platelet ratio would be optimum for clinical use to confirm independent predictors of patients with invasive aspergillosis. CONCLUSIONS: Gamma-glutamyl transpeptidase-platelet ratio is an independent, a useful predictor, and is superior to other evaluated markers in the diagnosis of inflammation in invasive aspergillosis. Gamma-glutamyl transpeptidase-platelet ratio may also be a helpful biomarker for clinicians to follow-up the inflammatory process of these patients.


Subject(s)
Aspergillosis , gamma-Glutamyltransferase , Aspergillosis/pathology , Blood Platelets , Humans , Inflammation/pathology , Liver Cirrhosis/pathology , Platelet Count , ROC Curve , Retrospective Studies
13.
Lancet Infect Dis ; 21(11): e356-e362, 2021 11.
Article in English | MEDLINE | ID: mdl-34599872

ABSTRACT

Spinal epidural abscess caused by Aspergillus spp is a debilitating form of invasive aspergillosis that can easily be misdiagnosed as spinal tuberculosis due to shared risk factors and clinical features. In this Grand Round, we describe a case of thoracic aspergillus spinal epidural abscess in a patient with underlying HIV infection. The initial diagnostic consideration was that of spinal tuberculosis. Consequently, despite positive microbiological cultures of Aspergillus fumigatus, antifungal therapy was delayed until histopathological evaluation of the affected tissue confirmed the presence of fungal hyphae. The patient showed an initial favourable response after surgical removal of the infected focus, but unfortunately never returned to premorbid functioning. This case highlights the importance of early diagnosis, urgent surgery, and prompt antifungal therapy for the management of aspergillus spinal epidural abscesses. Associated morbidity and mortality can be substantially increased if physicians fail to recognise this condition and do not institute appropriate and timely surgical and medical treatment.


Subject(s)
Aspergillosis/diagnosis , Aspergillosis/pathology , Epidural Abscess/microbiology , HIV Infections/complications , HIV-1 , Tuberculosis/diagnosis , Adult , Antifungal Agents/administration & dosage , Antifungal Agents/therapeutic use , Aspergillosis/drug therapy , Aspergillus , Epidural Abscess/drug therapy , Female , Humans , Itraconazole/administration & dosage , Itraconazole/therapeutic use , Tuberculosis/pathology , Voriconazole/administration & dosage , Voriconazole/therapeutic use
15.
PLoS Pathog ; 17(8): e1009806, 2021 08.
Article in English | MEDLINE | ID: mdl-34370772

ABSTRACT

Although considered effective treatment for many yeast fungi, the therapeutic efficacy of the echinocandin class of antifungals for invasive aspergillosis (IA) is limited. Recent studies suggest intense kinase- and phosphatase-mediated echinocandin adaptation in A. fumigatus. To identify A. fumigatus protein kinases required for survival under echinocandin stress, we employed CRISPR/Cas9-mediated gene targeting to generate a protein kinase disruption mutant library in a wild type genetic background. Cell wall and echinocandin stress screening of the 118 disruption mutants comprising the library identified only five protein kinase disruption mutants displaying greater than 4-fold decreased echinocandin minimum effective concentrations (MEC) compared to the parental strain. Two of these mutated genes, the previously uncharacterized A. fumigatus sepL and sidB genes, were predicted to encode protein kinases functioning as core components of the Septation Initiation Network (SIN), a tripartite kinase cascade that is necessary for septation in fungi. As the A. fumigatus SIN is completely uncharacterized, we sought to explore these network components as effectors of echinocandin stress survival. Our data show that mutation of any single SIN kinase gene caused complete loss of hyphal septation and increased susceptibility to cell wall stress, as well as widespread hyphal damage and loss of viability in response to echinocandin stress. Strikingly, mutation of each SIN kinase gene also resulted in a profound loss of virulence characterized by lack of tissue invasive growth. Through the deletion of multiple novel regulators of hyphal septation, we show that the non-invasive growth phenotype is not SIN-kinase dependent, but likely due to hyphal septation deficiency. Finally, we also find that echinocandin therapy is highly effective at eliminating residual tissue burden in mice infected with an aseptate strain of A. fumigatus. Together, our findings suggest that inhibitors of septation could enhance echinocandin-mediated killing while simultaneously limiting the invasive potential of A. fumigatus hyphae.


Subject(s)
Aspergillosis/drug therapy , Aspergillus fumigatus/drug effects , Echinocandins/pharmacology , Fungal Proteins/metabolism , Lung/drug effects , Protein Kinases/deficiency , Animals , Antifungal Agents/pharmacology , Aspergillosis/enzymology , Aspergillosis/microbiology , Aspergillosis/pathology , Aspergillus fumigatus/enzymology , Female , Lung/microbiology , Lung/pathology , Mice
16.
PLoS Pathog ; 17(8): e1009794, 2021 08.
Article in English | MEDLINE | ID: mdl-34437655

ABSTRACT

Aspergillus fumigatus is a saprophytic, filamentous fungus found in soils and compost and the causative agent of several pulmonary diseases in humans, birds, and other mammals. A. fumigatus and other filamentous fungi grow as networks of filamentous hyphae that have characteristics of a classic microbial biofilm. These characteristics include production of an extracellular matrix (ECM), surface adhesion, multicellularity, and increased antimicrobial drug resistance. A. fumigatus biofilm growth occurs in vivo at sites of infection, highlighting the importance of defining mechanisms underlying biofilm development and associated emergent properties. We propose that there are 3 distinct phases in the development of A. fumigatus biofilms: biofilm initiation, immature biofilm, and mature biofilm. These stages are defined both temporally and by unique genetic and structural changes over the course of development. Here, we review known mechanisms within each of these stages that contribute to biofilm structure, ECM production, and increased resistance to contemporary antifungal drugs. We highlight gaps in our understanding of biofilm development and function that when addressed are expected to aid in the development of novel antifungal therapies capable of killing filamentous fungal biofilms.


Subject(s)
Antifungal Agents/pharmacology , Aspergillosis/microbiology , Aspergillus fumigatus/growth & development , Biofilms/growth & development , Drug Resistance, Fungal , Animals , Aspergillosis/drug therapy , Aspergillosis/pathology , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/physiology , Biofilms/drug effects , Disease Progression , Humans , Microbial Viability
17.
J Exp Med ; 218(9)2021 09 06.
Article in English | MEDLINE | ID: mdl-34313733

ABSTRACT

Pulmonary innate immunity is required for host defense; however, excessive neutrophil inflammation can cause life-threatening acute lung injury. B lymphocytes can be regulatory, yet little is known about peripheral transitional IgM+ B cells in terms of regulatory properties. Using single-cell RNA sequencing, we discovered eight IgM+ B cell subsets with unique gene regulatory networks in the lung circulation dominated by transitional type 1 B and type 2 B (T2B) cells. Lung intravital confocal microscopy revealed that T2B cells marginate in the pulmonary capillaries via CD49e and require CXCL13 and CXCR5. During lung inflammation, marginated T2B cells dampened excessive neutrophil vascular inflammation via the specialized proresolving molecule lipoxin A4 (LXA4). Exogenous CXCL13 dampened excessive neutrophilic inflammation by increasing marginated B cells, and LXA4 recapitulated neutrophil regulation in B cell-deficient mice during inflammation and fungal pneumonia. Thus, the lung microvasculature is enriched in multiple IgM+ B cell subsets with marginating capillary T2B cells that dampen neutrophil responses.


Subject(s)
B-Lymphocytes/pathology , Lung/pathology , Neutrophils/pathology , Pneumonia/pathology , Animals , Aspergillosis/microbiology , Aspergillosis/pathology , B-Lymphocytes/physiology , Capillaries/pathology , Cell Adhesion , Chemokine CXCL13/metabolism , Integrin alpha5/metabolism , Intravital Microscopy , Lipoxins/metabolism , Lung/blood supply , Lung/diagnostic imaging , Mice, Mutant Strains , Pneumonia/diagnostic imaging , Receptors, CXCR5/metabolism , Single-Cell Analysis
18.
J Immunol Res ; 2021: 5538612, 2021.
Article in English | MEDLINE | ID: mdl-34222495

ABSTRACT

PURPOSE: Aspergillus fumigatus, as an opportunistic fungus, has developed a series of escape mechanisms under the host's immune response to obtain nutrients and promote fungal growth in the hostile environment. The immune escape of pathogens may be through suppressing the inflammatory response mediated by regulatory T cells (Tregs). The aim of this study was to explore whether A. fumigatus influences Gasdermin-D-dependent pyroptosis of the lung by regulating Toll-like receptor 2-mediated regulatory T cell differentiation. METHODS: Collect peripheral blood from patients with A. fumigatus. ELISA kits we used to detect the expression levels of IL-1ß, IL-6, IL-2R, and IL-10 in the serum and flow cytometry to detect the percentage of CD4+CD25+Foxp3+ Tregs in the patients' peripheral blood mononuclear cells (PBMCs). The mouse model of A. fumigatus infection was constructed by tracheal instillation. The pathological changes in the lungs of the mice were observed under a microscope. The fungal load in the lung tissue was determined by the plate colony count. ELISA kit was used to detect the lung tissue homogenate proinflammatory cytokines TNF-α, IL-6, CCL2, and VEGF. Q-PCR was used for the detection of the expression of Foxp3 and TLR2 genes in the lung. Western blot was used for the detection of the expression of TLR2, Gasdermin-D (GSDMD), IL-1α, and IL-1ß in the lung. Flow cytometry was used to detect splenic CD4+CD25+FOXP3+ Tregs. Using magnetic beads to extract CD4+ T cells from mice spleen, the effects of A. fumigatus conidia or TLR2 inhibitor (C29) to differentiate CD4+ T cells in vitro were tested. RESULTS: The expression of Foxp3 and TLR2 in the lung tissue of mice infected with A. fumigatus increased, and we observed that the proportion of Tregs in both A. fumigatus infection patients and mice was upregulated. After using the CD25 neutralizing antibody, the number of Tregs in the mice spleen was significantly reduced. However, lung damage was reduced and the ability to clear lung fungi was enhanced. We found that the Tregs in TLR2-/- mice were significantly reduced and the nonlethal dose of A. fumigatus conidia did not cause severe lung damage in TLR2-/- mice. Compared with that of wild-type mice, the fungal burden in the lung of TLR2-deficient mice was reduced and the knockout of TLR2 changed the expression of GSDMD, IL-1α, and IL-1ß in A. fumigatus. In in vitro experiments, we found that the inhibition of TLR2 can reduce Treg differentiation. CONCLUSIONS: A. fumigatus triggers CD4+CD25+FOXP3+ Treg proliferation and differentiation by activating the TLR2 pathway, which may be a potential mechanism for evading host defenses in A. fumigatus. This effect can modulate GSDMD-dependent pyroptosis and may partly involve TRL2 signaling.


Subject(s)
Aspergillosis/immunology , T-Lymphocytes, Regulatory/immunology , Toll-Like Receptor 2/metabolism , Animals , Aspergillosis/microbiology , Aspergillosis/pathology , Aspergillus fumigatus/immunology , Cell Differentiation/immunology , Disease Models, Animal , Host Microbial Interactions/immunology , Humans , Immune Evasion , Intracellular Signaling Peptides and Proteins/metabolism , Lung/immunology , Lung/microbiology , Lung/pathology , Lymphocyte Activation , Male , Mice , Mice, Knockout , Phosphate-Binding Proteins/metabolism , Pyroptosis/immunology , T-Lymphocytes, Regulatory/metabolism , Toll-Like Receptor 2/genetics
19.
Rev. Assoc. Med. Bras. (1992) ; 67(7): 1021-1025, July 2021. tab, graf
Article in English | LILACS | ID: biblio-1346962

ABSTRACT

SUMMARY OBJECTIVE: Gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index are three systemic immune and inflammation indexes that were investigated for their diagnostic and prognostic proficiencies in cardiovascular diseases and cancers. However, their predictive values for invasive aspergillosis have not yet been studied. The aim of this study was to evaluate Gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index levels and their diagnostic values in invasive aspergillosis. METHODS: A total of 23 patients with invasive aspergillosis and 23 sex- and age-matched healthy participants were included in this study. Complete blood count parameters and liver function tests were studied. Gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index were calculated. RESULTS: Leukocyte, neutrophil, lymphocyte, and monocyte levels were statistically significantly higher in IA group (p=0.031, p=0.027, p=0.033, and p=0.001, respectively). In invasive aspergillosis group, platelets were numerically lower; Aspartate transaminase, alanine aminotransferase, and lactic dehydrogenase levels were numerically higher than those in control group but differences between levels were not statistically significant (p>0.05). The γ-glutamyl transpeptidase levels of patients were statistically significantly higher (p=0.007), and in addition, statistically significant differences were found between groups in terms of gamma-glutamyl transpeptidase-platelet ratio, system inflammation response index, and systemic immune inflammation index (p<0.001, p=0.037, p=0.001, respectively). Receiver operating characteristic analysis was performed, and areas under the curves were evaluated. gamma-glutamyl transpeptidase-platelet ratio had the higher area under the curve than systemic immune inflammation index and system inflammation response index (AUC 0.849, 0.798, 0.693, respectively). The results from receiver operating characteristic analysis of the data suggested that the use of a cutoff value of 0.15 for gamma-glutamyl transpeptidase-platelet ratio would be optimum for clinical use to confirm independent predictors of patients with invasive aspergillosis. CONCLUSIONS: Gamma-glutamyl transpeptidase-platelet ratio is an independent, a useful predictor, and is superior to other evaluated markers in the diagnosis of inflammation in invasive aspergillosis. Gamma-glutamyl transpeptidase-platelet ratio may also be a helpful biomarker for clinicians to follow-up the inflammatory process of these patients.


Subject(s)
Humans , Aspergillosis/pathology , gamma-Glutamyltransferase , Platelet Count , Blood Platelets , Retrospective Studies , ROC Curve , Inflammation/pathology , Liver Cirrhosis/pathology
20.
N Z Med J ; 134(1536): 41-51, 2021 06 04.
Article in English | MEDLINE | ID: mdl-34140712

ABSTRACT

BACKGROUND: Azole resistance in Aspergillus fumigatus (A. fumigatus) is increasing globally. A pan-azole-resistant isolate prompted genetic analysis of local azole-resistant isolates to determine resistance genotypes. METHODS: All A. fumigatus complex isolates were tested by the broth colorimetric micro-dilution method, Sensititre® YeastOne® (SYO) (TREK Diagnostic Systems, West Sussex, England). Epidemiological cutoff values derived from the Clinical & Laboratory Standards Institute method were used to determine the proportion of non-wild-type (non-WT) isolates (ie, those with an increased likelihood to harbour acquired mechanisms of resistance). Non-WT isolates were identified by ß-tubulin gene sequencing and the genotype for azole resistance was determined. The history of the patient with the first pan-resistant isolate was reviewed along with the treatment history of patients with azole-resistant strains. RESULTS: From January 2001 to August 2020, antifungal susceptibility testing was performed on 260 A. fumigatus complex isolates: six isolates were non-WT for one or more azole agent, two A. fumigatus sensu stricto and four other members within the species complex: two A. fischeri and two A. lentulus. There were three non-WT isolates for amphotericin B, three for itraconazole, five for posaconazole and five for voriconazole. All six non-WT strains were isolated in the past nine years (P<0.01), and four in the past three years. Azole-resistance genotyping for the A. fumigatus sensu stricto isolates detected amino acid changes at hot spots in the cyp51A gene: one at G54E and one at G138C. All six isolates were WT for caspofungin. Five of the six patients with azole-resistant strains had previous azole treatment, and the patient with the pan-azole-resistant strain had been on continuous azole treatment for 42 months preceding strain isolation. CONCLUSIONS: New Zealand can be added to the growing list of countries with azole-resistant A. fumigatus complex isolates, including pan-azole resistance in A. fumigatus sensu stricto. While uncommon and mostly found in cryptic species within the complex, azole resistance is increasing. The results provide a baseline for monitoring this emerging antifungal resistance trend in A. fumigatus in New Zealand.


Subject(s)
Antifungal Agents/pharmacology , Aspergillosis/microbiology , Aspergillus fumigatus/drug effects , Azoles/pharmacology , Drug Resistance, Fungal , Amphotericin B/pharmacology , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Aspergillosis/drug therapy , Aspergillosis/pathology , Aspergillus fumigatus/genetics , Azoles/therapeutic use , Humans , Lung/pathology , Male , Microbial Sensitivity Tests , Middle Aged , New Zealand , Retrospective Studies
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