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1.
J Proteome Res ; 23(5): 1634-1648, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38572994

ABSTRACT

The delay in making a correct diagnosis of Candida auris causes concern in the healthcare system setting, and immunoproteomics studies are important to identify immunoreactive proteins for new diagnostic strategies. In this study, immunocompetent murine systemic infections caused by non-aggregative and aggregative phenotypes of C. auris and by Candida albicans and Candida haemulonii were carried out, and the obtained sera were used to study their immunoreactivity against C. auris proteins. The results showed higher virulence, in terms of infection signs, weight loss, and histopathological damage, of the non-aggregative isolate. Moreover, C. auris was less virulent than C. albicans but more than C. haemulonii. Regarding the immunoproteomics study, 13 spots recognized by sera from mice infected with both C. auris phenotypes and analyzed by mass spectrometry corresponded to enolase, phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase, and phosphoglycerate mutase. These four proteins were also recognized by sera obtained from human patients with disseminated C. auris infection but not by sera obtained from mice infected with C. albicans or Aspergillus fumigatus. Spot identification data are available via ProteomeXchange with the identifier PXD049077. In conclusion, this study showed that the identified proteins could be potential candidates to be studied as new diagnostic or even therapeutic targets for C. auris.


Subject(s)
Candida , Candidiasis , Immunoglobulin G , Animals , Mice , Candida/immunology , Candida/pathogenicity , Humans , Candidiasis/immunology , Candidiasis/microbiology , Candidiasis/blood , Immunoglobulin G/blood , Antigens, Fungal/immunology , Antigens, Fungal/blood , Proteomics/methods , Candida albicans/immunology , Candida albicans/pathogenicity , Fungal Proteins/immunology , Phosphoglycerate Mutase/immunology , Phosphoglycerate Kinase/immunology , Glyceraldehyde-3-Phosphate Dehydrogenases/immunology , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Antibodies, Fungal/blood , Antibodies, Fungal/immunology , Female , Virulence
2.
Front Cell Infect Microbiol ; 14: 1327299, 2024.
Article in English | MEDLINE | ID: mdl-38343890

ABSTRACT

In this study, two distinct in vitro infection models of Aspergillus fumigatus, using murine macrophages (RAW264.7) and human lung epithelial cells (A549), were employed to identify the genes important for fungal adaptation during infection. Transcriptomic analyses of co-incubated A. fumigatus uncovered 140 fungal genes up-regulated in common between both models that, when compared with a previously published in vivo transcriptomic study, allowed the identification of 13 genes consistently up-regulated in all three infection conditions. Among them, the maiA gene, responsible for a critical step in the L-phenylalanine degradation pathway, was identified. Disruption of maiA resulted in a mutant strain unable to complete the Phe degradation pathway, leading to an excessive production of pyomelanin when this amino acid served as the sole carbon source. Moreover, the disruption mutant exhibited noticeable cell wall abnormalities, with reduced levels of ß-glucans within the cell wall but did not show lack of chitin or mannans. The maiA-1 mutant strain induced reduced inflammation in primary macrophages and displayed significantly lower virulence in a neutropenic mouse model of infection. This is the first study linking the A. fumigatus maiA gene to fungal cell wall homeostasis and virulence.


Subject(s)
Aspergillus fumigatus , Fungal Proteins , Animals , Humans , Mice , Aspergillus fumigatus/metabolism , Cell Wall/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Homeostasis , Virulence/genetics
3.
Microbes Infect ; 26(4): 105305, 2024.
Article in English | MEDLINE | ID: mdl-38296157

ABSTRACT

The liver, and more specifically, the liver sinusoidal endothelial cells, constitute the beginning of one of the most important responses for the elimination of hematogenously disseminated Candida albicans. Therefore, we aimed to study the mechanisms involved in the interaction between these cells and C. albicans. Transcriptomics-based analysis showed an increase in the expression of genes related to the immune response (including receptors, cytokines, and adhesion molecules), as well as to aerobic glycolysis. Further in vitro analyses showed that IL-6 production in response to C. albicans is controlled by MyD88- and SYK-pathways, suggesting an involvement of Toll-like and C-type lectin receptors and the subsequent activation of the MAP-kinases and c-Fos/AP-1 transcription factor. In addition, liver sinusoidal endothelial cells undergo metabolic reprogramming towards aerobic glycolysis induced by C. albicans, as confirmed by the increased Extracellular Acidification Rate and the overexpression of enolase (Eno2), hexonikase (Hk2) and glucose transporter 1 (Slc2a1). In conclusion, these results indicate that the hepatic endothelium responds to C. albicans by increasing aerobic glycolysis and promoting an inflammatory environment.


Subject(s)
Candida albicans , Endothelial Cells , Glycolysis , Liver , Candida albicans/immunology , Endothelial Cells/metabolism , Endothelial Cells/microbiology , Animals , Liver/metabolism , Liver/microbiology , Syk Kinase/metabolism , Interleukin-6/metabolism , Interleukin-6/genetics , Mice , Myeloid Differentiation Factor 88/metabolism , Inflammation/metabolism , Gene Expression Profiling , Candidiasis/immunology , Candidiasis/microbiology , Candidiasis/metabolism
4.
FEMS Microbiol Rev ; 47(3)2023 05 19.
Article in English | MEDLINE | ID: mdl-37286896

ABSTRACT

The most common genetic hereditary disease affecting Caucasians is cystic fibrosis (CF), which is caused by autosomal recessive mutations in the CFTR gene. The most serious consequence is the production of a thick and sticky mucus in the respiratory tract, which entraps airborne microorganisms and facilitates colonization, inflammation and infection. Therefore, the present article compiles the information about the microbiota and, particularly, the inter-kingdom fungal-bacterial interactions in the CF lung, the molecules involved and the potential effects that these interactions may have on the course of the disease. Among the bacterial compounds, quorum sensing-regulated molecules such as homoserine lactones, phenazines, rhamnolipids, quinolones and siderophores (pyoverdine and pyochelin) stand out, but volatile organic compounds, maltophilin and CF-related bacteriophages are also explained. These molecules exhibit diverse antifungal mechanisms, including iron starvation and induction of reactive oxygen and nitrogen species production. The fungal compounds are less studied, but they include cell wall components, siderophores, patulin and farnesol. Despite the apparent competition between microorganisms, the persistence of significant rates of bacterial-fungal co-colonization in CF suggests that numerous variables influence it. In conclusion, it is crucial to increase scientific and economic efforts to intensify studies on the bacterial-fungal inter-kingdom interactions in the CF lung.


Subject(s)
Cystic Fibrosis , Microbiota , Humans , Cystic Fibrosis/genetics , Cystic Fibrosis/microbiology , Siderophores , Bacteria , Lung/microbiology
5.
J Fungi (Basel) ; 9(2)2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36836272

ABSTRACT

The detection of Scedosporium/Lomentospora is still based on non-standardized low-sensitivity culture procedures. This fact is particularly worrying in patients with cystic fibrosis (CF), where these fungi are the second most common filamentous fungi isolated, because a poor and delayed diagnosis can worsen the prognosis of the disease. To contribute to the discovery of new diagnostic strategies, a rapid serological dot immunobinding assay (DIA) that allows the detection of serum IgG against Scedosporium/Lomentospora in less than 15 min was developed. A crude protein extract from the conidia and hyphae of Scedosporium boydii was employed as a fungal antigen. The DIA was evaluated using 303 CF serum samples (162 patients) grouped according to the detection of Scedosporium/Lomentospora in the respiratory sample by culture, obtaining a sensitivity and specificity of 90.48% and 79.30%, respectively; positive and negative predictive values of 54.81% and 96.77%, and an efficiency of 81.72%. The clinical factors associated with the results were also studied using a univariate and a multivariate analysis, which showed that Scedosporium/Lomentospora positive sputum, elevated anti-Aspergillus serum IgG and chronic Pseudomonas aeruginosa infection were significantly associated with a positive result in DIA, while Staphylococcus aureus positive sputum showed a negative association. In conclusion, the test developed can offer a complementary, rapid, simple and sensitive method to contribute to the diagnosis of Scedosporium/Lomentospora in patients with CF.

6.
J Appl Microbiol ; 133(6): 3534-3545, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35988051

ABSTRACT

INTRODUCTION: Quantitative reverse transcription PCR (RT-qPCR) is the leading tool to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Given that it will almost certainly continue to coexist with other respiratory viruses in the coming years, our study aimed to design a multiplex PCR system not affected by supplier outages and with reduced cost compared to the existing commercially available kits. METHODS AND RESULTS: In this study, combinations of four primers/probe sets were used to construct a flexible RT-qPCR assay which is capable of discriminating between SARS-CoV-2 and the seasonal human coronavirus HCoV-OC43, or even influenza A virus. Additionally, the human RPP30 gene was used as an internal control. To demonstrate the robustness of the assay, it was applied to a collection of 150 clinical samples. The results showed 100% sensitivity and specificity compared to the automatized system used at the hospital and were better when indeterminate samples were analysed. CONCLUSIONS: This study provides an efficient method for the simultaneous detection of SARS-CoV-2, HCoV-OC43 and influenza A virus, and its efficacy has been tested on clinical samples showing outstanding results. SIGNIFICANCE AND IMPACT OF THE STUDY: The multiplex RT-qPCR design offers an accessible and economical alternative to commercial detection kits for hospitals and laboratories with limited economic resources or facing situations of supply shortage.


Subject(s)
COVID-19 , Influenza A virus , Humans , SARS-CoV-2/genetics , Multiplex Polymerase Chain Reaction/methods , Influenza A virus/genetics , COVID-19/diagnosis , Sensitivity and Specificity , Nasopharynx
7.
J Fungi (Basel) ; 7(12)2021 Dec 14.
Article in English | MEDLINE | ID: mdl-34947056

ABSTRACT

The Añana Salt Valley in Spain is an active continental solar saltern formed 220 million years ago. To date, no fungal genomic studies of continental salterns have been published, although DNA metabarcoding has recently expanded researchers' ability to study microbial community structures. Accordingly, the aim of this present study was to evaluate fungal diversity using the internal transcribed spacer (ITS) metabarcoding at different locations along the saltern (springs, ponds, and groundwater) to describe the fungal community of this saline environment. A total of 380 fungal genera were detected. The ubiquity of Saccharomyces was observed in the saltern, although other halotolerant and halophilic fungi like Wallemia, Cladosporium, and Trimmatostroma were also detected. Most of the fungi observed in the saltern were saprotrophs. The fungal distribution appeared to be influenced by surrounding conditions, such as the plant and soil contact, cereal fields, and vineyards of this agricultural region.

8.
J Fungi (Basel) ; 7(11)2021 Nov 03.
Article in English | MEDLINE | ID: mdl-34829223

ABSTRACT

The activity of fumagillin, a mycotoxin produced by Aspergillus fumigatus, has not been studied in depth. In this study, we used a commercial fumagillin on cultures of two cell types (A549 pneumocytes and RAW 264.7 macrophages). This toxin joins its target, MetAP2 protein, inside cells and, as a result, significantly reduces the electron chain activity, the migration, and the proliferation ability on the A549 cells, or affects the viability and proliferation ability of the RAW 264.7 macrophages. However, the toxin stimulates the germination and double branch hypha production of fungal cultures, pointing out an intrinsic resistant mechanism to fumagillin of fungal strains. In this study, we also used a fumagillin non-producer A. fumigatus strain (∆fmaA) as well as its complemented strain (∆fmaA::fmaA) and we tested the fumagillin secretion of the fungal strains using an Ultra High-Performance Liquid Chromatography (UHPLC) method. Furthermore, fumagillin seems to protect the fungus against phagocytosis in vitro, and during in vivo studies using infection of immunosuppressed mice, a lower fungal burden in the lungs of mice infected with the ∆fmaA mutant was demonstrated.

9.
J Fungi (Basel) ; 7(7)2021 Jun 28.
Article in English | MEDLINE | ID: mdl-34203370

ABSTRACT

Aspergillus fumigatus is a ubiquitous soil decomposer and an opportunistic pathogen that is characterized by its large metabolic machinery for acquiring nutrients from media. Lately, an ever-increasing number of genes involved in fungal nutrition has been associated with its virulence. Of these, nitrogen, iron, and zinc metabolism-related genes are particularly noteworthy, since 78% of them have a direct implication in virulence. In this review, we describe the sensing, uptake and regulation process of the acquisition of these nutrients, the connections between pathways and the virulence-implicated genes. Nevertheless, only 40% of the genes mentioned in this review have been assayed for roles in virulence, leaving a wide field of knowledge that remains uncertain and might offer new therapeutic and diagnostic targets.

10.
J Fungi (Basel) ; 7(2)2021 Jan 22.
Article in English | MEDLINE | ID: mdl-33499053

ABSTRACT

Infections caused by the opportunistic pathogens Scedosporium/Lomentospora are on the rise. This causes problems in the clinic due to the difficulty in diagnosing and treating them. This review collates information published on immune response against these fungi, since an understanding of the mechanisms involved is of great interest in developing more effective strategies against them. Scedosporium/Lomentospora cell wall components, including peptidorhamnomannans (PRMs), α-glucans and glucosylceramides, are important immune response activators following their recognition by TLR2, TLR4 and Dectin-1 and through receptors that are yet unknown. After recognition, cytokine synthesis and antifungal activity of different phagocytes and epithelial cells is species-specific, highlighting the poor response by microglial cells against L. prolificans. Moreover, a great number of Scedosporium/Lomentospora antigens have been identified, most notably catalase, PRM and Hsp70 for their potential medical applicability. Against host immune response, these fungi contain evasion mechanisms, inducing host non-protective response, masking fungal molecular patterns, destructing host defense proteins and decreasing oxidative killing. In conclusion, although many advances have been made, many aspects remain to be elucidated and more research is necessary to shed light on the immune response to Scedosporium/Lomentospora.

11.
Front Cell Infect Microbiol ; 10: 602089, 2020.
Article in English | MEDLINE | ID: mdl-33324582

ABSTRACT

The detection and diagnosis of the opportunistic fungi Scedosporium spp. and Lomentospora prolificans still relies mainly on low-sensitive culture-based methods. This fact is especially worrying in Cystic Fibrosis (CF) patients in whom these fungal species are frequently isolated and may increase the risk of suffering from an infection or other health problems. Therefore, with the purpose of developing a serologic detection method for Scedosporium/Lomentospora, four different Scedosporium boydii protein extracts (whole cell protein extract, secretome, total cell surface and conidial surface associated proteins) were studied by ELISA to select the most useful for IgG detection in sera from CF patients. The four extracts were able to discriminate the Scedosporium/Lomentospora-infected from Aspergillus-infected and non-infected patients. However, the whole cell protein extract was the one selected, as it was the one with the highest output in terms of protein concentration per ml of fungal culture used, and its discriminatory capacity was the best. The ELISA test developed was then assayed with 212 sera from CF patients and it showed to be able to detect Scedosporium spp. and Lomentospora prolificans with very high sensitivity and specificity, 86%-100% and 93%-99%, respectively, depending on the cut-off value chosen (four values were proposed A450nm= 0.5837, A450nm= 0.6042, A450nm= 0.6404, and A450nm= 0.7099). Thus, although more research is needed to reach a standardized method, this ELISA platform offers a rapid, low-cost and easy solution to detect these elusive fungi through minimally invasive sampling, allowing the monitoring of the humoral response to fungal presence.


Subject(s)
Ascomycota , Cystic Fibrosis , Scedosporium , Antifungal Agents , Cystic Fibrosis/complications , Enzyme-Linked Immunosorbent Assay , Humans
12.
Rev Iberoam Micol ; 37(3-4): 81-86, 2020.
Article in English | MEDLINE | ID: mdl-33168341

ABSTRACT

BACKGROUND: Mucor circinelloides is an opportunistic fungus capable of causing mucormycosis, a highly aggressive infection of quick spreading. Besides, it also has a high mortality rate due to late diagnosis and difficult treatment. AIMS: In this study we have identified the most immunoreactive proteins of the secretome and the total protein extract of M. circinelloides using sera from immunocompromised infected mice. METHODS: The proteins of the secretome and the total extract were analyzed by two-dimensional electrophoresis and the most immunoreactive antigens were detected by Western Blot, facing the sera of immunocompromised infected mice to the proteins obtained in both extracts of M. circinelloides. RESULTS: Seven antigens were detected in the secretome extract, and two in the total extract, all of them corresponding only to three proteins. The enzyme enolase was detected in both extracts, while triosephosphate isomerase was detected in the secretome, and heat shock protein HSS1 in the total extract. CONCLUSIONS: In this work the most immunoreactive antigens of the secretome and the total extract of M. circinelloides were identified. The identified proteins are well known fungal antigens and, therefore, these findings can be useful for future research into alternatives for the diagnosis and treatment of mucormycosis.


Subject(s)
Mucor , Mucormycosis , Animals , Mice , Mucormycosis/diagnosis , Oxidation-Reduction
13.
Rev. iberoam. micol ; 37(3/4): 81-86, jul.-oct. 2020. ilus, tab
Article in English | IBECS | ID: ibc-200357

ABSTRACT

BACKGROUND: Mucor circinelloides is an opportunistic fungus capable of causing mucormycosis, a highly aggressive infection of quick spreading. Besides, it also has a high mortality rate due to late diagnosis and difficult treatment. AIMS: In this study we have identified the most immunoreactive proteins of the secretome and the total protein extract of M. circinelloides using sera from immunocompromised infected mice. METHODS: The proteins of the secretome and the total extract were analyzed by two-dimensional electrophoresis and the most immunoreactive antigens were detected by Western Blot, facing the sera of immunocompromised infected mice to the proteins obtained in both extracts of M. circinelloides. RESULTS: Seven antigens were detected in the secretome extract, and two in the total extract, all of them corresponding only to three proteins. The enzyme enolase was detected in both extracts, while triosephosphate isomerase was detected in the secretome, and heat shock protein HSS1 in the total extract. CONCLUSIONS: In this work the most immunoreactive antigens of the secretome and the total extract of M. circinelloides were identified. The identified proteins are well known fungal antigens and, therefore, these findings can be useful for future research into alternatives for the diagnosis and treatment of mucormycosis


ANTECEDENTES: Mucor circinelloides es un hongo oportunista causante de la mucormicosis, una infección altamente agresiva y de rápida expansión. Además, también presenta una alta mortalidad debido al diagnóstico tardío y el difícil tratamiento. OBJETIVOS: En este estudio se han identificado las proteínas más inmunorreactivas del secretoma y del extracto total de proteínas de M. circinelloides mediante el uso de sueros obtenidos de ratones inmunodeprimidos infectados. MÉTODOS: Las proteínas del secretoma y del extracto total se analizaron mediante electroforesis bidimensional y se detectaron los antígenos más inmunorreactivos mediante Western Blot, enfrentando el suero de los ratones inmunodeprimidos infectados a las proteínas obtenidas en ambos extractos de M. circinelloides. RESULTADOS: Se identificaron 7 antígenos en el secretoma y 2 en el extracto total, todos ellos correspondientes a 3 proteínas. La enolasa se detectó en ambos extractos, mientras que la triosafosfato isomerasa se detectó en el secretoma, y la proteína de choque térmico HSS1 en el extracto total. CONCLUSIONES: En este trabajo se identificaron los antígenos más inmunorreactivos del secretoma y del extracto total de M. circinelloides. Todas las proteínas identificadas son antígenos fúngicos muy conocidos y, por ello, estos resultados pueden ser de gran utilidad en futuras investigaciones relacionadas con la mejora del diagnóstico y el tratamiento de la mucormicosis


Subject(s)
Animals , Mice , Antigens, Fungal/immunology , Immunocompromised Host , Mucormycosis/immunology , Mucor/immunology , Two-Dimensional Difference Gel Electrophoresis , Models, Animal
14.
Sci Rep ; 10(1): 9206, 2020 06 08.
Article in English | MEDLINE | ID: mdl-32514067

ABSTRACT

Candida albicans is a commensal yeast able to cause life threatening invasive infections particularly in immunocompromised patients. Despite the availability of antifungal treatments, mortality rates are still unacceptably high and drug resistance is increasing. We, therefore, generated the Ca37 monoclonal antibody against the C. albicans alcohol dehydrogenase (Adh) 1. Our data showed that Ca37 was able to detect C. albicans cells, and it bound to Adh1 in yeast and Adh2 in hyphae among the cell wall-associated proteins. Moreover, Ca37 was able to inhibit candidal growth following 18 h incubation time and reduced the minimal inhibitory concentration of amphotericin B or fluconazole when used in combination with those antifungals. In addition, the antibody prolonged the survival of C. albicans infected-Galleria mellonella larvae, when C. albicans was exposed to antibody prior to inoculating G. mellonella or by direct application as a therapeutic agent on infected larvae. In conclusion, the Ca37 monoclonal antibody proved to be effective against C. albicans, both in vitro and in vivo, and to act together with antifungal drugs, suggesting Adh proteins could be interesting therapeutic targets against this pathogen.


Subject(s)
Alcohol Dehydrogenase/immunology , Antibodies, Monoclonal/pharmacology , Candida albicans/enzymology , Fungal Proteins/immunology , Alcohol Dehydrogenase/deficiency , Alcohol Dehydrogenase/genetics , Amphotericin B/pharmacology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , Antifungal Agents/pharmacology , Candida albicans/drug effects , Candida albicans/pathogenicity , Candidiasis/drug therapy , Candidiasis/microbiology , Candidiasis/veterinary , Fluconazole/pharmacology , Hyphae/enzymology , Larva/drug effects , Microbial Sensitivity Tests , Moths/drug effects , Moths/growth & development , Moths/microbiology , Virulence
15.
Vaccines (Basel) ; 7(4)2019 Dec 10.
Article in English | MEDLINE | ID: mdl-31835471

ABSTRACT

The high mortality rates of Lomentospora prolificans infections are due, above all, to the tendency of the fungus to infect weakened hosts, late diagnosis and a lack of effective therapeutic treatments. To identify proteins of significance for diagnosis, therapy or prophylaxis, immunoproteomics-based studies are especially important. Consequently, in this study murine disseminated infections were carried out using L. prolificans, Scedosporium aurantiacum, Scedosporium boydii and Aspergillus fumigatus, and their sera used to identify the most immunoreactive proteins of L. prolificans total extract and secreted proteins. The results showed that L. prolificans was the most virulent species and its infections were characterized by a high fungal load in several organs, including the brain. The proteomics study showed a high cross-reactivity between Scedosporium/Lomentospora species, but not with A. fumigatus. Among the antigens identified were, proteasomal ubiquitin receptor, carboxypeptidase, Vps28, HAD-like hydrolase, GH16, cerato-platanin and a protein of unknown function that showed no or low homology with humans. Finally, Hsp70 deserves a special mention as it was the main antigen recognized by Scedosporium/Lomentospora species in both secretome and total extract. In conclusion, this study identifies antigens of L. prolificans that can be considered as potential candidates for use in diagnosis and as therapeutic targets and the production of vaccines.

16.
Toxins (Basel) ; 12(1)2019 12 20.
Article in English | MEDLINE | ID: mdl-31861936

ABSTRACT

Fumagillin is a mycotoxin produced, above all, by the saprophytic filamentous fungus Aspergillus fumigatus. This mold is an opportunistic pathogen that can cause invasive aspergillosis, a disease that has high mortality rates linked to it. Its ability to adapt to environmental stresses through the production of secondary metabolites, including several mycotoxins (gliotoxin, fumagillin, pseurotin A, etc.) also seem to play an important role in causing these infections. Since the discovery of the A. fumigatus fumagillin in 1949, many studies have focused on this toxin and in this review we gather all the information currently available. First of all, the structural characteristics of this mycotoxin and the different methods developed for its determination are given in detail. Then, the biosynthetic gene cluster and the metabolic pathway involved in its production and regulation are explained. The activity of fumagillin on its target, the methionine aminopeptidase type 2 (MetAP2) enzyme, and the effects of blocking this enzyme in the host are also described. Finally, the applications that this toxin and its derivatives have in different fields, such as the treatment of cancer and its microsporicidal activity in the treatment of honeybee hive infections with Nosema spp., are reviewed. Therefore, this work offers a complete review of all the information currently related to the fumagillin mycotoxin secreted by A. fumigatus, important because of its role in the fungal infection process but also because it has many other applications, notably in beekeeping, the treatment of infectious diseases, and in oncology.


Subject(s)
Aspergillus fumigatus/chemistry , Cyclohexanes/toxicity , Fatty Acids, Unsaturated/toxicity , Mycotoxins/toxicity , Animals , Bees , Cyclohexanes/chemistry , Fatty Acids, Unsaturated/biosynthesis , Fatty Acids, Unsaturated/chemistry , Humans , Mycotoxins/biosynthesis , Mycotoxins/chemistry , Sesquiterpenes/chemistry , Sesquiterpenes/toxicity
17.
Virulence ; 9(1): 1548-1561, 2018.
Article in English | MEDLINE | ID: mdl-30251593

ABSTRACT

Virulence mechanisms of the pathogenic fungus Aspergillus fumigatus are multifactorial and depend on the immune state of the host, but little is known about the fungal mechanism that develops during the process of lung invasion. In this study, microarray technology was combined with a histopathology evaluation of infected lungs so that the invasion strategy followed by the fungus could be described. To achieve this, an intranasal mice infection was performed to extract daily fungal samples from the infected lungs over four days post-infection. The pathological study revealed a heavy fungal progression throughout the lung, reaching the blood vessels on the third day after exposure and causing tissue necrosis. One percent of the fungal genome followed a differential expression pattern during this process. Strikingly, most of the genes of the intertwined fumagillin/pseurotin biosynthetic gene cluster were upregulated as were genes encoding lytic enzymes such as lipases, proteases (DppIV, DppV, Asp f 1 or Asp f 5) and chitinase (chiB1) as well as three genes related with pyomelanin biosynthesis process. Furthermore, we demonstrate that fumagillin is produced in an in vitro pneumocyte cell line infection model and that loss of fumagillin synthesis reduces epithelial cell damage. These results suggest that fumagillin contributes to tissue damage during invasive aspergillosis. Therefore, it is probable that A. fumigatus progresses through the lungs via the production of the mycotoxin fumagillin combined with the secretion of lytic enzymes that allow fungal growth, angioinvasion and the disruption of the lung parenchymal structure.


Subject(s)
Aspergillus fumigatus/genetics , Aspergillus fumigatus/pathogenicity , Fatty Acids, Unsaturated/genetics , Invasive Pulmonary Aspergillosis/pathology , Lung/microbiology , Alveolar Epithelial Cells/metabolism , Animals , Cell Line , Cyclohexanes , Female , Genome, Fungal , Host-Pathogen Interactions , Lung/pathology , Mice , Microarray Analysis , Multigene Family , Pyrrolidinones/metabolism , Sesquiterpenes , Virulence
18.
Med Mycol ; 56(suppl_1): 102-125, 2018 Apr 01.
Article in English | MEDLINE | ID: mdl-29538735

ABSTRACT

Species of Scedosporium and Lomentospora are considered as emerging opportunists, affecting immunosuppressed and otherwise debilitated patients, although classically they are known from causing trauma-associated infections in healthy individuals. Clinical manifestations range from local infection to pulmonary colonization and severe invasive disease, in which mortality rates may be over 80%. These unacceptably high rates are due to the clinical status of patients, diagnostic difficulties, and to intrinsic antifungal resistance of these fungi. In consequence, several consortia have been founded to increase research efforts on these orphan fungi. The current review presents recent findings and summarizes the most relevant points, including the Scedosporium/Lomentospora taxonomy, environmental distribution, epidemiology, pathology, virulence factors, immunology, diagnostic methods, and therapeutic strategies.


Subject(s)
Antifungal Agents/therapeutic use , Ascomycota/physiology , Drug Resistance, Multiple, Fungal/genetics , Mycoses/microbiology , Scedosporium/physiology , Antifungal Agents/pharmacology , Ascomycota/classification , Ascomycota/drug effects , Ascomycota/genetics , Combined Modality Therapy , Ecology , Host-Pathogen Interactions/immunology , Humans , Immunocompromised Host , Molecular Typing , Mycoses/diagnosis , Mycoses/pathology , Mycoses/therapy , Opportunistic Infections/diagnosis , Opportunistic Infections/microbiology , Opportunistic Infections/pathology , Opportunistic Infections/therapy , Scedosporium/classification , Scedosporium/drug effects , Scedosporium/genetics , Surgical Procedures, Operative , Virulence Factors
19.
Cell Microbiol ; 20(8): e12847, 2018 08.
Article in English | MEDLINE | ID: mdl-29582549

ABSTRACT

Lomentospora (Scedosporium) prolificans is an opportunistic pathogen capable of causing invasive infections in immunocompromised patients. The fungus is able to disseminate via the bloodstream finally arriving at the central nervous system producing neurological symptoms and, in many cases, patient death. In this context, microglial cells, which are the resident immune cells in the central nervous system, may play an important role in these infections. However, this aspect of anti-L. prolificans immunity has been poorly researched to date. Thus, the interactions and activity of microglial cells against L. prolificans were analysed, and the results show that there was a remarkable impairment in their performance regarding phagocytosis, the development of oxidative burst, and in the production of pro-inflammatory cytokines, compared with macrophages. Interestingly, L. prolificans displays great growth also when challenged with immune cells, even when inside them. We also proved that microglial phagocytosis of the fungus is highly dependent on mannose receptor and especially on dectin-1. Taken together, these data provide evidence for an impaired microglial response against L. prolificans and contribute to understanding the pathobiology of its neurotropism.


Subject(s)
Host-Pathogen Interactions , Immune Evasion , Microglia/immunology , Microglia/microbiology , Scedosporium/immunology , Scedosporium/pathogenicity , Animals , Cells, Cultured , Cytokines/metabolism , Macrophages/immunology , Macrophages/microbiology , Mice , Phagocytosis , Respiratory Burst , Scedosporium/growth & development
20.
Mycopathologia ; 183(1): 273-289, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28484941

ABSTRACT

Cystic fibrosis (CF) is a genetic disorder that increases the risk of suffering microbial, including fungal, infections. In this paper, proteomics-based information was collated relating to secreted and cell wall proteins with potential medical applications from the most common filamentous fungi in CF, i.e., Aspergillus and Scedosporium/Lomentospora species. Among the Aspergillus fumigatus secreted allergens, ß-1,3-endoglucanase, the alkaline protease 1 (Alp1/oryzin), Asp f 2, Asp f 13/15, chitinase, chitosanase, dipeptidyl-peptidase V (DppV), the metalloprotease Asp f 5, mitogillin/Asp f 1, and thioredoxin reductase receive a special mention. In addition, the antigens ß-glucosidase 1, catalase, glucan endo-1,3-ß-glucosidase EglC, ß-1,3-glucanosyltransferases Gel1 and Gel2, and glutaminase A were also identified in secretomes of other Aspergillus species associated with CF: Aspergillus flavus, Aspergillus niger, Aspergillus nidulans, and Aspergillus terreus. Regarding cell wall proteins, cytochrome P450 and eEF-3 were proposed as diagnostic targets, and alkaline protease 2 (Alp2), Asp f 3 (putative peroxiredoxin pmp20), probable glycosidases Asp f 9/Crf1 and Crf2, GPI-anchored protein Ecm33, ß-1,3-glucanosyltransferase Gel4, conidial hydrophobin Hyp1/RodA, and secreted aspartyl protease Pep2 as protective vaccines in A. fumigatus. On the other hand, for Scedosporium/Lomentospora species, the heat shock protein Hsp70 stands out as a relevant secreted and cell wall antigen. Additionally, the secreted aspartyl proteinase and an ortholog of Asp f 13, as well as the cell wall endo-1,3-ß-D-glucosidase and 1,3-ß-glucanosyl transferase, were also found to be significant proteins. In conclusion, proteins mentioned in this review may be promising candidates for developing innovative diagnostic and therapeutic tools for fungal infections in CF patients.


Subject(s)
Aspergillus/chemistry , Fungal Proteins/analysis , Proteome/analysis , Proteomics/methods , Scedosporium/chemistry , Allergens/analysis , Antigens, Fungal/analysis , Cell Wall/chemistry , Cystic Fibrosis/microbiology , Humans
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