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1.
Proc Natl Acad Sci U S A ; 119(21): e2200413119, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35576468

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection fatality rate (IFR) doubles with every 5 y of age from childhood onward. Circulating autoantibodies neutralizing IFN-α, IFN-ω, and/or IFN-ß are found in ∼20% of deceased patients across age groups, and in ∼1% of individuals aged <70 y and in >4% of those >70 y old in the general population. With a sample of 1,261 unvaccinated deceased patients and 34,159 individuals of the general population sampled before the pandemic, we estimated both IFR and relative risk of death (RRD) across age groups for individuals carrying autoantibodies neutralizing type I IFNs, relative to noncarriers. The RRD associated with any combination of autoantibodies was higher in subjects under 70 y old. For autoantibodies neutralizing IFN-α2 or IFN-ω, the RRDs were 17.0 (95% CI: 11.7 to 24.7) and 5.8 (4.5 to 7.4) for individuals <70 y and ≥70 y old, respectively, whereas, for autoantibodies neutralizing both molecules, the RRDs were 188.3 (44.8 to 774.4) and 7.2 (5.0 to 10.3), respectively. In contrast, IFRs increased with age, ranging from 0.17% (0.12 to 0.31) for individuals <40 y old to 26.7% (20.3 to 35.2) for those ≥80 y old for autoantibodies neutralizing IFN-α2 or IFN-ω, and from 0.84% (0.31 to 8.28) to 40.5% (27.82 to 61.20) for autoantibodies neutralizing both. Autoantibodies against type I IFNs increase IFRs, and are associated with high RRDs, especially when neutralizing both IFN-α2 and IFN-ω. Remarkably, IFRs increase with age, whereas RRDs decrease with age. Autoimmunity to type I IFNs is a strong and common predictor of COVID-19 death.


Assuntos
Anticorpos Neutralizantes , Autoanticorpos , Autoimunidade , COVID-19 , Interferon Tipo I , SARS-CoV-2 , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Autoanticorpos/sangue , COVID-19/imunologia , COVID-19/mortalidade , Feminino , Humanos , Interferon Tipo I/imunologia , Masculino , Pessoa de Meia-Idade , Risco
2.
Mult Scler ; 30(6): 755-758, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38247156

RESUMO

BACKGROUND: Fungal infections of the central nervous system usually affect immunocompromised patients. Primary Aspergillus myelitis has never been described. REPORT: A 45-year-old immunocompetent male with subacute paraplegia was treated for inflammatory myelitis before clinical deterioration requiring mechanical ventilation. Purulent meningitis preceded the formation of a paraspinal nodule biopsied by neurosurgery. Histopathological analysis revealed the presence of fungal hyphae, and polymerase chain reaction was positive for Aspergillus fumigatus. No cause of immunodeficiency was identified in this patient. DISCUSSION: Primary Aspergillus myelitis may be confused with inflammatory myelitis and should be considered even in the absence of apparent immunosuppression.


Assuntos
Mielite , Humanos , Masculino , Pessoa de Meia-Idade , Mielite/microbiologia , Aspergillus fumigatus/isolamento & purificação , Imunocompetência , Imageamento por Ressonância Magnética , Neuroaspergilose , Aspergilose/complicações , Aspergilose/diagnóstico , Antifúngicos/uso terapêutico
4.
Antimicrob Agents Chemother ; 67(3): e0113022, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36853002

RESUMO

We report the first identification of a fluconazole-resistant Candida parapsilosis (FR-Cp) strain in our hospital, which subsequently caused an outbreak involving 17 patients (12 deaths) within a 26-bed French intensive care unit. Microsatellite genotyping confirmed that all FR-Cp isolates belonged to the same clone. Given recent reports of rapid dissemination of these emerging clones, routine testing of azole susceptibility for all Candida parapsilosis isolates should be encouraged, at least in ICU patients.


Assuntos
Candida parapsilosis , Fluconazol , Humanos , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Candida parapsilosis/genética , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica/genética , Testes de Sensibilidade Microbiana , Unidades de Terapia Intensiva , Surtos de Doenças , Hospitais
5.
Artigo em Inglês | MEDLINE | ID: mdl-33593841

RESUMO

The worldwide emergence of multidrug-resistant pathogenic fungi is a threat to human health. At this very moment, an emergence of Candida parapsilosis isolates harbouring a resistance to fluconazole, one of the most popular antifungal drugs, is being described in several countries. We seek to better understanding the epidemiology, pathogenicity and transmission of resistant Candida parapsilosis Faced with an outbreak of invasive infections due to resistant isolates of C. parapsilosis, we performed a 7-year retrospective and prospective analysis of 283 C. parapsilosis isolates collected in 240 patients, among who 111 had invasive candidiasis. Study included review of hospital records, genotyping analysis and susceptibility testing that allow determining the type and outcome of infections, as well as the spatial and temporal spread of clusters. Overall the incidence of azole resistance was 7.5%. Genotyping analysis unveiled several previously undetected outbreaks and clonal spread of susceptible and resistant isolates over a long period of time. In comparison with susceptible isolates, resistant ones have a more restricted genetic diversity and seem to be more likely to spread and more frequently associated with invasive infections. In intensive care units, patients with invasive infections due to resistant isolates had poorer outcome (overall mortality at day 30 of 40%; 4/10) than susceptible ones (overall mortality at day 30 of 26.5%; 9/34). Our results suggest that the propensity of C. parapsilosis to spread on an epidemic fashion is underestimated, which warrants reinforced control and epidemiological survey of this species.

6.
J Clin Immunol ; 43(6): 1093-1103, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37209324

RESUMO

Autoantibodies (auto-Abs) neutralizing type I interferons (IFNs) are found in the blood of at least 15% of unvaccinated patients with life-threatening COVID-19 pneumonia. We report here the presence of auto-Abs neutralizing type I IFNs in the bronchoalveolar lavage (BAL) of 54 of the 415 unvaccinated patients (13%) with life-threatening COVID-19 pneumonia tested. The 54 individuals with neutralizing auto-Abs in the BAL included 45 (11%) with auto-Abs against IFN-α2, 37 (9%) with auto-Abs against IFN-ω, 54 (13%) with auto-Abs against IFN-α2 and/or ω, and five (1%) with auto-Abs against IFN-ß, including three (0.7%) with auto-Abs neutralizing IFN-α2, IFN-ω, and IFN-ß, and two (0.5%) with auto-Abs neutralizing IFN-α2 and IFN-ß. Auto-Abs against IFN-α2 also neutralize the other 12 subtypes of IFN-α. Paired plasma samples were available for 95 patients. All seven patients with paired samples who had detectable auto-Abs in BAL also had detectable auto-Abs in plasma, and one patient had auto-Abs detectable only in blood. Auto-Abs neutralizing type I IFNs are, therefore, present in the alveolar space of at least 10% of patients with life-threatening COVID-19 pneumonia. These findings suggest that these auto-Abs impair type I IFN immunity in the lower respiratory tract, thereby contributing to hypoxemic COVID-19 pneumonia.


Assuntos
COVID-19 , Interferon Tipo I , Humanos , Autoanticorpos , Interferon-alfa , Lavagem Broncoalveolar
7.
Am J Respir Crit Care Med ; 203(3): 307-317, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33480831

RESUMO

Rationale: Whether severe coronavirus disease (COVID-19) is a significant risk factor for the development of invasive fungal superinfections is of great medical interest and remains, for now, an open question.Objectives: We aim to assess the occurrence of invasive fungal respiratory superinfections in patients with severe COVID-19.Methods: We conducted the study on patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related pneumonia admitted to five ICUs in France who had respiratory and serum sampling performed for specific screening of fungal complications.Measurements and Main Results: The study population included a total of 145 patients; the median age was 55 years old. Most of them were male (n = 104; 72%), were overweight (n = 99; 68%), and had hypertension (n = 83; 57%) and diabetes (n = 46; 32%). Few patients presented preexisting host risk factors for invasive fungal infection (n = 20; 14%). Their global severity was high; all patients were on invasive mechanical ventilation, and half (n = 73, 54%) were on extracorporeal membrane oxygenation support. Mycological analysis included 2,815 mycological tests (culture, galactomannan, ß-glucan, and PCR) performed on 475 respiratory samples and 532 sera. A probable/putative invasive pulmonary mold infection was diagnosed in 7 (4.8%) patients and linked to high mortality. Multivariate analysis indicates a significantly higher risk for solid organ transplant recipients (odds ratio, = 4.66; interquartile range, 1.98-7.34; P = 0.004). False-positive fungal test and clinically irrelevant colonization, which did not require the initiation of antifungal treatment, was observed in 25 patients (17.2%).Conclusions: In patients with no underlying immunosuppression, severe SARS-CoV-2-related pneumonia seems at low risk of invasive fungal secondary infection, especially aspergillosis.


Assuntos
COVID-19/terapia , Infecções Fúngicas Invasivas/epidemiologia , Pneumopatias Fúngicas/epidemiologia , Idoso , COVID-19/complicações , COVID-19/mortalidade , Feminino , França , Hospitalização , Humanos , Infecções Fúngicas Invasivas/diagnóstico , Pneumopatias Fúngicas/diagnóstico , Masculino , Pessoa de Meia-Idade , Respiração Artificial , Estudos Retrospectivos , Fatores de Risco
8.
Clin Infect Dis ; 72(8): 1379-1385, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-32155262

RESUMO

BACKGROUND: Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergillosis (IA). This multicenter study describes the epidemiology and outcome of A. ustus infections. METHODS: Patients with A. ustus isolated from any clinical specimen were retrospectively identified in 22 hospitals from 8 countries. When available, isolates were sent for species identification (BenA/CaM sequencing) and antifungal susceptibility testing. Additional cases were identified by review of the literature. Cases were classified as proven/probable IA or no infection, according to standard international criteria. RESULTS: Clinical report forms were obtained for 90 patients, of whom 27 had proven/probable IA. An additional 45 cases were identified from literature review for a total of 72 cases of proven/probable IA. Hematopoietic cell and solid-organ transplant recipients accounted for 47% and 33% cases, respectively. Only 8% patients were neutropenic at time of diagnosis. Ongoing antimold prophylaxis was present in 47% of cases. Pulmonary IA represented 67% of cases. Primary or secondary extrapulmonary sites of infection were observed in 46% of cases, with skin being affected in 28% of cases. Multiple antifungal drugs were used (consecutively or in combination) in 67% of cases. The 24-week mortality rate was 58%. A. calidoustus was the most frequent causal agent. Minimal inhibitory concentrations encompassing 90% isolates (MIC90) were 1, 8, >16, and 4 µg/mL for amphotericin B, voriconazole, posaconazole, and isavuconazole, respectively. CONCLUSIONS: Aspergillus ustus IA mainly occurred in nonneutropenic transplant patients and was frequently associated with extrapulmonary sites of infection. Mortality rate was high and optimal antifungal therapy remains to be defined.


Assuntos
Aspergilose , Infecções Fúngicas Invasivas , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/epidemiologia , Aspergillus , Humanos , Infecções Fúngicas Invasivas/diagnóstico , Infecções Fúngicas Invasivas/tratamento farmacológico , Infecções Fúngicas Invasivas/epidemiologia , Estudos Retrospectivos
9.
Antimicrob Agents Chemother ; 65(12): e0149521, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34543091

RESUMO

We determined the susceptibility of 182 Fusarium species isolates to five antifungal drugs (amphotericin B, voriconazole, posaconazole, isavuconazole, and terbinafine) by the EUCAST method. Based on the latest taxonomic insights, isolates collected from 20 European centers were distributed into seven complexes and 27 species. The susceptibility was variable, depending on the species. Comparison with the gradient concentration strip method, which was used for 77 isolates, showed essential agreement values for voriconazole, posaconazole, isavuconazole, and amphotericin B of 17%, 91%, 83%, and 70%, respectively.


Assuntos
Antifúngicos , Fusarium , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Voriconazol/farmacologia
10.
J Clin Microbiol ; 59(10): e0129921, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34319807

RESUMO

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) represents a promising tool for the rapid and efficient identification of molds, but improvements are still necessary to achieve satisfactory results when identifying cryptic species. Here, we aimed to validate a new web application, MSI-2, which replaces MSI-1, an application that was built and deployed online in 2017. For the evaluation, we gathered 633 challenging isolates obtained from daily hospital practice that were first identified with DNA-based methods, and we submitted their corresponding mass spectra to three identification programs (Bruker, MSI-1, and MSI-2). The MSI-2 application had a better identification performance at the species level than MSI-1 and Bruker, reaching 83.25% correct identifications, compared with 63.19% (MSI-1), 38.07% (Bruker with a 1.7 threshold), and 21.8% (Bruker with a 2.0 threshold). The MSI-2 application performed especially well for Aspergillus and Fusarium species, including for many cryptic species, reaching 90% correct identifications for Aspergillus species and 78% for Fusarium species compared to 69% and 43% with MSI-1. Such an improvement may have a positive impact on patient management by facilitating the identification of cryptic species potentially associated with a specific antifungal resistance profile.


Assuntos
Fungos , Fusarium , Aspergillus/genética , Bases de Dados Factuais , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Mycoses ; 64(11): 1346-1353, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34181773

RESUMO

OBJECTIVES: Aspergillus cryptic species are increasingly recognised causes of Aspergillus diseases, including life-threatening invasive aspergillosis (IA). However, as their accurate identification remains challenging in a routine practice, few is known from a clinical and epidemiological perspective. Recently, the MSI application has emerged as a powerful tool for the detection and identification of Aspergillus cryptic species. We aimed to use to the network of users of the MSI application to conduct a multicentre prospective screening of Aspergillus cryptic species-related IA and analyse their epidemiological, clinical and mycological characteristics. METHODS: Over a 27-month period, the clinical involvement of 369 Aspergillus cryptic isolates, from 13 French and Danish MSI application users, was prospectively analysed. Species identification was confirmed by DNA-sequencing and antifungal susceptibility testing was performed using EUCAST reference method. Fifty-one A fumigatus sensu stricto invasive cases were also analysed. RESULTS: Fifteen cryptic isolates were responsible of IA. Eight species were involved, including 5 cases related to the species A sublatus. These species showed high rate of in vitro low susceptibility to antifungal drugs. In comparison with A fumigatus sensu stricto invasive cases, pre-exposure to azole drugs was significantly associated with cryptic IA (P = .02). DISCUSSION: This study brings new insights in cryptic species related IA and underlines the importance to identify accurately at the species level these Aspergillus isolates. The increasing use of antifungal drugs might lead in the future to an epidemiologic shift with an emergence of resistant isolates involved in IA.


Assuntos
Aspergillus/classificação , Aspergilose Pulmonar Invasiva/microbiologia , Adulto , Idoso , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Farmacorresistência Fúngica , Feminino , França/epidemiologia , Humanos , Aspergilose Pulmonar Invasiva/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Emerg Infect Dis ; 26(7): 1636-1637, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32343223

RESUMO

Invasive pulmonary aspergillosis is a complication in critically ill patients with acute respiratory distress syndrome, especially those with severe influenza pneumonia. We report a fatal case of invasive pulmonary aspergillosis in an immunocompetent patient in France who had severe coronavirus disease-associated pneumonia.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Aspergilose Pulmonar/etiologia , Idoso , COVID-19 , Infecções por Coronavirus/mortalidade , Humanos , Imunocompetência , Masculino , Pandemias , Pneumonia Viral/mortalidade , Aspergilose Pulmonar/mortalidade , SARS-CoV-2
13.
Emerg Infect Dis ; 26(9)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32819454

RESUMO

Nine new human invasive infections caused by the keratinophilic fungi Nannizziopsis obscura have been reported in France since 2004. The patients had variable clinical manifestations, had frequent dissemination, were mainly T-cell immunocompromised, and all originated from sub-Saharan West Africa. Before collection of the isolates, the etiologies of these infections were often misidentified, underscoring the extent of microscopic and cultural polymorphisms. All isolates but 1 had low MICs for the 8 antifungal drugs tested. When treated, patients received mainly azole therapy. Two of 7 patients with a known outcome died. We performed multilocus sequence analysis of N. obscura clinical strains and several strains of Nannizziopsis spp. isolated from reptiles. The human strains were clearly differentiated from the animal strains. N. obscura might be endemic to West Africa and responsible for undetected infections, which might become reactivated when immunosuppression occurs. N. obscura infection is probably underestimated because only sequencing enables proper identification.


Assuntos
Antifúngicos , África Subsaariana , África Ocidental/epidemiologia , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , França/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Onygenales
14.
Haematologica ; 105(2): 478-489, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31171644

RESUMO

The Bruton tyrosine kinase inhibitor ibrutinib has become a leading therapy against chronic lymphoid leukemia. Recently, ibrutinib has been associated with the occurrence of invasive fungal infections, in particular invasive aspergillosis. The mechanisms underlying the increased susceptibility to fungal infections associated with exposure to ibrutinib are currently unknown. Innate immunity, in particular polymer-phonuclear neutrophils, represents the cornerstone of anti-Aspergillus immunity; however, the potential impact of ibrutinib on neutrophils has been little studied. Our study investigated the response to Aspergillus fumigatus and neutrophil function in patients with chronic lymphoid leukemia or lymphoma, who were undergoing ibrutinib therapy. We studied the consequences of ibrutinib exposure on the functions and anti-Aspergillus responses of neutrophils obtained from healthy donors and 63 blood samples collected at different time points from 32 patients receiving ibrutinib for lymphoid malignancies. We used both flow cytometry and video-microscopy approaches to analyze neutrophils' cell surface molecule expression, cytokine production, oxidative burst, chemotaxis and killing activity against Aspergillus Ibrutinib is associated, both in vitro and in patients under treatment, with multiple functional defects in neutrophils, including decreased production of reactive oxygen species, impairment of their capacity to engulf Aspergillus and inability to efficiently kill germinating conidia. Our results demonstrate that ibrutinib-exposed neutrophils develop significant functional defects that impair their response against Aspergillus fumigatus, providing a plausible explanation for the emergence of invasive aspergillosis in ibrutinib-treated patients.


Assuntos
Aspergilose , Aspergillus fumigatus , Adenina/análogos & derivados , Aspergilose/tratamento farmacológico , Humanos , Neutrófilos , Piperidinas , Esporos Fúngicos
15.
Med Mycol ; 57(8): 962-968, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30690478

RESUMO

The taxonomy of Aspergillus species has recently been revolutionized with the introduction of cryptic species and section concepts. However, their species-level identification in routine laboratories remains a challenge. The aim of this study was to prospectively assess the identification accuracy of cryptic species of Aspergillus in various laboratories using the mass spectrometry identification (MSI) platform, an independent and freely accessible online mass spectrometry database. Over a 12-month period, when a select set of MSI users identified cryptic species, they were contacted and requested to send the isolates to our laboratory for sequence-based identification. Sequence and MSI identification results were then compared. During the study period, 5108 Aspergillus isolates were identified using MSI including 1477 (28.9%) cryptic species. A total of 245 isolates that corresponded to 56 cryptic species and 13 sections were randomly selected for DNA sequencing confirmation. Agreement between the two methods was 99.6% at the section level and 66.1% at the species level. However, almost all discrepancies (72/83, 86.7%) were misidentifications between closely related cryptic species belonging to the same section. Fifty-one isolates from noncryptic species were also identified, thus yielding 100% and 92.2% agreement at the section and species level, respectively. Although the MSI fungus database is a reliable tool to identify Aspergillus at the section level, the database still requires adjustment to correctly identify rare or cryptic species at the species level. Nevertheless, the application properly differentiated between cryptic and sensu stricto species in the same section, thus alerting on possible specific isolate characteristics.


Assuntos
Aspergillus/química , Aspergillus/classificação , Bases de Dados Factuais , Internet , Técnicas Microbiológicas/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos
16.
Artigo em Inglês | MEDLINE | ID: mdl-27855078

RESUMO

Liver transplant recipients are at risk of invasive fungal infections, especially candidiasis. Echinocandin is recommended as prophylactic treatment but is increasingly associated with resistance. Our aim was to assess echinocandin drug resistance in Candida spp. isolated from liver transplant recipients treated with this antifungal class. For this, all liver-transplanted patients in a University Hospital (Créteil, France) between January and June of 2013 and 2015 were included. Susceptibilities of Candida isolates to echinocandins were tested by Etest and the EUCAST reference method. Isolates were analyzed by FKS sequencing and genotyped based on microsatellites or multilocus sequence typing (MLST) profiles. Ninety-four patients were included, and 39 patients were colonized or infected and treated with echinocandin. Echinocandin resistance appeared in 3 (8%) of the treated patients within 1 month of treatment. One patient was colonized by resistant Candida glabrata, one by resistant Candida dubliniensis, and one by resistant Candida albicans Molecular analysis found three mutations in FKS2 HS1 (F659S, S663A, and D666E) for C. glabrata and one mutation in FKS1 HS1 (S645P) for C. dubliniensis and C. albicans Susceptible and resistant isolates belonged to the same genotype. To our knowledge, this is the first study on echinocandin resistance in Candida spp. in a liver transplant population. Most resistant isolates were found around/in digestive sites, perhaps due to lower diffusion of echinocandin in these sites. This work documents the risk of emergence of resistance to echinocandin, even after short-term treatment.


Assuntos
Candida/efeitos dos fármacos , Candida/genética , Farmacorresistência Fúngica/efeitos dos fármacos , Equinocandinas/farmacologia , Transplante de Fígado , Adulto , Idoso , Candida/isolamento & purificação , Equinocandinas/uso terapêutico , Feminino , França , Proteínas Fúngicas/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Proteína 2 Homóloga a MutS/genética , Mutação
17.
Cell Microbiol ; 18(12): 1881-1891, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27603677

RESUMO

The galactomannan is a major cell wall molecule of Aspergillus fumigatus. This molecule is composed of a linear mannan with a repeating unit composed of four α1,6 and α1,2 linked mannose with side chains of galactofuran. To obtain a better understanding of the mannan biosynthesis in A. fumigatus, it was decided to undertake the successive deletion of the 11 genes which are putative orthologs of the mannosyltransferases responsible for establishing α1,6 and α1,2 mannose linkages in yeast. These deletions did not lead to a reduction of the mannan content of the cell wall of the mycelium of A. fumigatus. In contrast, the mannan content of the conidial cell wall was reduced and this reduction was associated with a partial disorganization of the cell wall leading to defects in conidial survival both in vitro and in vivo.


Assuntos
Aspergillus fumigatus/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Mananas/metabolismo , Manosiltransferases/genética , Micélio/metabolismo , Esporos Fúngicos/metabolismo , Animais , Aspergilose/microbiologia , Aspergilose/patologia , Aspergillus fumigatus/genética , Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/patogenicidade , Configuração de Carboidratos , Parede Celular/química , Parede Celular/metabolismo , Proteínas Fúngicas/metabolismo , Galactose/análogos & derivados , Deleção de Genes , Interações Hospedeiro-Patógeno , Mananas/química , Manose/química , Manose/metabolismo , Manosiltransferases/metabolismo , Camundongos , Micélio/genética , Micélio/crescimento & desenvolvimento , Micélio/patogenicidade , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/patogenicidade , Virulência
18.
J Allergy Clin Immunol ; 138(3): 860-868, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27132218

RESUMO

BACKGROUND: Neutrophils are key effectors against the widely distributed mold Aspergillus fumigatus, which is a major threat for immunocompromised patients, including allogeneic hematopoietic stem cell transplant (HSCT) recipients. Yet little is known about neutrophil activity over time after cell transplantation, especially regarding A fumigatus. OBJECTIVE: We aimed at assessing the activity of neutrophils on A fumigatus in allogeneic HSCT recipients at different posttransplantation time points. METHODS: We performed a longitudinal study involving 37 patients undergoing HSCT, drawing blood samples at engraftment and at 2, 6, and 10 months after the HSCT. Posttransplantation neutrophil activity in the recipients was compared with that of the respective donors. Neutrophil/A fumigatus coculture, flow cytometry, and video microscopy were used to assess neutrophil inhibition of fungal growth, cell/fungus interactions, reactive oxygen species production, major surface molecule expression, and neutrophil extracellular trap (NET) formation. RESULTS: The ability of neutrophils to interfere with Aspergillus species hyphal growth was impaired after HSCT. The administration of calcineurin inhibitors appeared to play an important role in this impairment. We also observed that post-HSCT neutrophils produced less NETs, which was correlated with increased fungal growth. Tapering immunosuppression led to the recuperation of inhibition capacity 10 months after HSCT. CONCLUSION: In HSCT recipients neutrophil-driven innate immunity to fungi is altered in the early posttransplantation period (between recovery from neutropenia and up to 6 months). This alteration is at least partly related to administration of calcineurin inhibitors and diminution of NETs production.


Assuntos
Aspergillus fumigatus/crescimento & desenvolvimento , Inibidores de Calcineurina/farmacologia , Transplante de Células-Tronco Hematopoéticas , Neutrófilos/efeitos dos fármacos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Adulto Jovem
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