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mSphere ; 4(6)2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694899


The release of extracellular vesicles (EVs) by fungi is a fundamental cellular process. EVs carry several biomolecules, including pigments, proteins, enzymes, lipids, nucleic acids, and carbohydrates, and are involved in physiological and pathological processes. EVs may play a pivotal role in the establishment of fungal infections, as they can interact with the host immune system to elicit multiple outcomes. It has been observed that, depending on the fungal pathogen, EVs can exacerbate or attenuate fungal infections. The study of the interaction between fungal EVs and the host immune system and understanding of the mechanisms that regulate those interactions might be useful for the development of new adjuvants as well as the improvement of protective immune responses against infectious or noninfectious diseases. In this review, we describe the immunomodulatory properties of EVs produced by pathogenic fungi and discuss their potential as adjuvants for prophylactic or therapeutic strategies.

Biomolecules ; 9(10)2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547546


Fungal diseases have been underestimated worldwide but constitute a substantial threat to several plant and animal species as well as to public health. The increase in the global population has entailed an increase in the demand for agriculture in recent decades. Accordingly, there has been worldwide pressure to find means to improve the quality and productivity of agricultural crops. Antifungal agents have been widely used as an alternative for managing fungal diseases affecting several crops. However, the unregulated use of antifungals can jeopardize public health. Application of fungicides in agriculture should be under strict regulation to ensure the toxicological safety of commercialized foods. This review discusses the use of antifungals in agriculture worldwide, the need to develop new antifungals, and improvement of regulations regarding antifungal use.

Nat Commun ; 8(1): 1968, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29213074


Cryptococcus neoformans is an encapsulated fungal pathogen that causes cryptococcosis, which is a major opportunistic infection in immunosuppressed individuals. Mammalian ß-galactoside-binding protein Galectin-3 (Gal-3) modulates the host innate and adaptive immunity, and plays significant roles during microbial infections including some fungal diseases. Here we show that this protein plays a role also in C. neoformans infection. We find augmented Gal-3 serum levels in human and experimental infections, as well as in spleen, lung, and brain tissues of infected mice. Gal-3-deficient mice are more susceptible to cryptococcosis than WT animals, as demonstrated by the higher fungal burden and lower animal survival. In vitro experiments show that Gal-3 inhibits fungal growth and exerts a direct lytic effect on C. neoformans extracellular vesicles (EVs). Our results indicate a direct role for Gal-3 in antifungal immunity whereby this molecule affects the outcome of C. neoformans infection by inhibiting fungal growth and reducing EV stability, which in turn could benefit the host.

Antifúngicos/imunologia , Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Criptococose/imunologia , Cryptococcus neoformans/efeitos dos fármacos , Galectina 3/imunologia , Galectina 3/farmacologia , Imunidade Adaptativa , Animais , Cápsulas Bacterianas/efeitos dos fármacos , Encéfalo/imunologia , Criptococose/microbiologia , Cryptococcus neoformans/crescimento & desenvolvimento , Cryptococcus neoformans/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Galectina 3/sangue , Galectina 3/genética , Expressão Gênica , Humanos , Pulmão/imunologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Baço/imunologia
Curr Genomics ; 17(2): 112-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27226767


Paracoccidioidomycosis is the most prevalent systemic mycosis in Latin America. It is caused by the temperature-dependent dimorphic fungus Paracoccidioides brasiliensis. The P. brasiliensis cell wall is a dynamic outer structure, composed of a network of glycoproteins and polysaccharides, such as chitin, glucan and N-glycosylated proteins. These glycoproteins can interact with the host to affect infection rates, and are known to perform other functions. We inhibited N-linked glycosylation using tunicamycin (TM), and then evaluated the expression of P. brasiliensis genes related to cell wall remodeling. Our results suggest that cell wall synthesis related genes, such as ß-1,3-glucanosyltransferase (PbGEL3), 1,3-ß-D-glucan synthase (PbFKS1), and α-1,4-amylase (PbAMY), as well as cell wall degrading related genes, such as N-acetyl-ß-D-glucosaminidase (PbNAG1), α-1,3-glucanase (PbAGN), and ß-1,3-glucanase (PbBGN1 and PbBGN2), have their expression increased by the N-glycosylation inhibition, as detected by qRT-PCR. The observed increases in gene expression levels reveal possible compensatory mechanisms for diminished enzyme activity due to the lack of glycosylation caused by TM.

PLoS One ; 10(12): e0144507, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26659253


Toxoplasma gondii is an obligate intracellular protozoan parasite found worldwide that is able to chronically infect almost all vertebrate species, especially birds and mammalians. Chitinases are essential to various biological processes, and some pathogens rely on chitinases for successful parasitization. Here, we purified and characterized a chitinase from T. gondii. The enzyme, provisionally named Tg_chitinase, has a molecular mass of 13.7 kDa and exhibits a Km of 0.34 mM and a Vmax of 2.64. The optimal environmental conditions for enzymatic function were at pH 4.0 and 50 °C. Tg_chitinase was immunolocalized in the cytoplasm of highly virulent T. gondii RH strain tachyzoites, mainly at the apical extremity. Tg_chitinase induced macrophage activation as manifested by the production of high levels of pro-inflammatory cytokines, a pathogenic hallmark of T. gondii infection. In conclusion, to our knowledge, we describe for the first time a chitinase of T. gondii tachyzoites and provide evidence that this enzyme might influence the pathogenesis of T. gondii infection.

Quitinases/imunologia , Ativação de Macrófagos/imunologia , Macrófagos Peritoneais/imunologia , Proteínas de Protozoários/imunologia , Toxoplasma/imunologia , Sequência de Aminoácidos , Animais , Quitinases/genética , Quitinases/metabolismo , Cromatografia Líquida , Citocinas/imunologia , Citocinas/metabolismo , Citoplasma/enzimologia , Interações Hospedeiro-Parasita/imunologia , Concentração de Íons de Hidrogênio , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Cinética , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/parasitologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Confocal , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Proteínas de Protozoários/química , Espectrometria de Massas em Tandem , Temperatura Ambiente , Toxoplasma/enzimologia , Toxoplasma/fisiologia