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2.
Braz J Microbiol ; 52(1): 5-18, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32440844

RESUMO

Sporotrichosis in immunocompromised patients has a high morbidity and may cause deaths. Particularly, patients with acquired immunodeficiency syndrome (AIDS) with low T CD4 counts develop a chronic disease, with severe and widespread forms. Recently, the ability of Sporothrix brasiliensis, the main agent of zoonotic sporotrichosis, to increase its virulence in a diabetic patient without HIV infection was described. Since it was a unique finding, it is not known how often this occurs in patients with chronic and refractory sporotrichosis. The aim of this study is to compare sequential Sporothrix isolates obtained from patients with sporotrichosis and AIDS in order to detect changes in virulence-related phenotypes and acquisition of antifungal resistance during the evolution of the disease. Fungal growth in different substrates, antifungal susceptibility, thermotolerance, resistance to oxidative stress, and production of hydrolytic enzymes were evaluated. Correlations were assessed between clinical and phenotypic variables. Sixteen isolates, all identified as S. brasiliensis, obtained from five patients were studied. They grew well on glucose and N-acetyl-D-glucosamine, but poorly on lactate. Except from isolates collected from two patients, which were non-wild type for terbinafine, they were considered wild type for the antifungal drugs tested. Thermotolerance of the isolates was moderate to high. Except for phytase and phospholipase, isolates were able to produce virulence-related enzymes on different levels. Changes in all studied phenotypes were observed during the course of the disease in some patients. The results show that the HIV-driven immunosuppression is more relevant than fungal phenotypes on the unfavorable outcomes of disseminated sporotrichosis.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Sporothrix/patogenicidade , Esporotricose/microbiologia , Acetilglucosamina/metabolismo , Adulto , Animais , Antifúngicos/farmacologia , Evolução Biológica , Farmacorresistência Fúngica , Feminino , Glucose/metabolismo , Humanos , Ácido Láctico/metabolismo , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Fenótipo , Sporothrix/efeitos dos fármacos , Sporothrix/genética , Sporothrix/metabolismo , Esporotricose/etiologia , Virulência/efeitos dos fármacos , Adulto Jovem
3.
Med Mycol ; 59(3): 301-304, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32944733

RESUMO

Sporotrichosis is a disease caused by thermally dimorphic fungi belonging to the Sporothrix schenckii complex. We report the occurrence of multiple cases of sporotrichosis in cats in Porto Alegre (RS), Brazil, from 2015 to 2019. A set of 21 fungal isolates were collected and the partial sequence of calmodulin (CAL) gene compared. All isolates were identified at phenotypic and molecular level as S. brasiliensis. Phylogenetic analysis showed the isolates clustered in two distinct groups, suggesting the presence of multiple genetic variants of S. brasiliensis in the region.


Assuntos
Doenças do Gato/microbiologia , Filogenia , Úlcera Cutânea/veterinária , Sporothrix/genética , Esporotricose/veterinária , Animais , Brasil , Gatos , Variação Genética , Análise de Sequência de DNA , Úlcera Cutânea/microbiologia , Sporothrix/classificação , Sporothrix/patogenicidade , Esporotricose/microbiologia
4.
Future Microbiol ; 15: 1217-1225, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33026880

RESUMO

Background: Sporotrichosis occurs through contact with contaminated soil and plant. However, the incidence of sporotrichosis as a zoonotic epidemic has increased, particularly in Rio de Janeiro. Aim: In this work, we decided to evaluate some T-cell phenotypes involved in the immune response. Materials & methods: We used flow cytometry to quantify TCD4+ and TCD8+ and Treg from immunocompetent and immunosuppressed mice infected with Sporothrix species with different levels of virulence and pathogenicity. Results: It was demonstrated the predominance of TCD4+ over the TCD8+ cells in both groups, inoculated with all the species, and percentages of Treg observed in infected immunocompetent mice. Conclusion: This regulatory phenotype can be associated with a protective immunity in the initial periods of infection.


Assuntos
Sporothrix/patogenicidade , Esporotricose/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Interações Hospedeiro-Patógeno/imunologia , Humanos , Contagem de Linfócitos , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Baço/imunologia , Sporothrix/isolamento & purificação , Esporotricose/microbiologia , Virulência
5.
Rev. bras. ciênc. vet ; 27(4): 183-187, out./dez. 2020. il.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1369656

RESUMO

A esporotricose é uma zoonose causada por fungos do gênero Sporothrix. Os gatos doentes têm importante potencial zoonótico e frequentemente revelam uma apresentação disseminada da doença. O objetivo deste relato de caso é descrever as características clínicas e anatomopatológicas de um caso de esporotricose felina refratária ao tratamento com apresentação clínica cutânea disseminada e sistêmica. Um felino macho de 3 anos de idade foi tratado para esporotricose com itraconazol e obteve resolução completa das lesões cutâneas. Porém, um ano após alta clínica, o animal apresentou aumento e ulceração da região nasal. Após cultura fúngica positiva para Sporothrix spp foi instituído tratamento com itraconazol 100mg associado ao iodeto de potássio 20mg por via oral diariamente e transcorrido 3 meses de tratamento, foi observada piora progressiva do sinais clínicos com disseminação de lesões para outras regiões do corpo. O animal foi submetido à eutanásia e encaminhado para necrópsia no Serviço de Anatomia Patológica da Faculdade de Veterinária da Universidade Federal Fluminense. Amostras da língua, pulmão, fígado, baço, rim, cérebro, linfonodo e pele foram coletadas para evidência de disseminação do agente fúngico e avaliação de alterações microscópicas. A coloração de metenamina de prata de Grocott foi utilizada para facilitar a visualização de leveduras sugestivas de Sporothrix spp nos cortes histológicos. Leveduras foram visualizadas em amostras de pele, língua, linfonodo, rim, fígado, baço e cérebro. No presente relato a disseminação do Sporothrixspp para diversos órgãos sinaliza a necessidade de uma minuciosa investigação dos casos graves de esporotricose felina para o tratamento adequado.


Sporotrichosis is a zoonosis caused by fungi of the genus Sporothrix. Sick cats have an significant zoonotic potential and often show a widespread presentation of the disease. The purpose of this case report is to describe the clinical and anatomopathological characteristics of a case of feline sporotrichosis refractory to treatment with disseminated and systemic cutaneous clinical presentation. A 3-year-old male feline was treated for sporotrichosis with itraconazole and achieved complete resolution of the skin lesions. However, one year after clinical discharge, the animal presented an increase and ulceration of the nasal region. After a positive fungal culture for Sporothrix spp, treatment with itraconazole 100mg associated with potassium iodide 20mg was instituted orally daily and after 3 months of treatment, a progressive worsening of the symptoms was observed with the spread of lesions to other regions of the body. The animal was euthanized and sent for necropsy at the Pathological Anatomy Service of the Veterinary Faculty of Universidade Federal Fluminense. Samples of the tongue, lung, liver, spleen, kidney, brain, lymph node, and skin were collected for evidence of spread of the fungal agent and evaluation of microscopic changes. Grocott silver methenamine staining was used to facilitate the visualization of yeasts suggestive of Sporothrix spp in histological sections. Yeasts were visualized in samples of skin, tongue, lymph node, kidney, liver, spleen, and brain. In the present report, the spread of Sporothrix spp to different organs signals the need for a thorough investigation of severe cases of feline sporotrichosis for the proper treatment.


Assuntos
Animais , Gatos , Autopsia/veterinária , Esporotricose/veterinária , Sporothrix/patogenicidade , Gatos/fisiologia , Itraconazol/uso terapêutico , Vírus da Imunodeficiência Felina , Vírus da Leucemia Felina
6.
Mycoses ; 63(12): 1311-1320, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32816371

RESUMO

BACKGROUND: An alternative therapy for sporotrichosis is necessary to reduce the treatment time and raise clinical efficacy. The 5-Aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) is a promising platform with which to treat mycoses. However, despite the worldwide prevalence of Sporothrix globosa, a causative agent of sporotrichosis, the effect of ALA-PDT on this pathogen has not been validated. OBJECTIVES: The aim of this study was to evaluate the effect of ALA-PDT on S globosa and the protection of melanin through an in vitro study. The mechanisms involved were also investigated. METHODS: To estimate the survival rate of S globosa treated with ALA-PDT and the protection offered by melanin, the conidia and yeast cells of wild-type S globosa (Mel+), other clinical strains, tricyclazole-treated Mel+ and an albino mutant strain (Mel-) were incubated with and without ALA or irradiation. Reactive oxygen species generation by Mel+ conidia induced by ALA-PDT was assayed. SEM and TEM were conducted to obverse ultrastructural changes in the conidia. A comet assay was performed to evaluate DNA damage. RESULTS: The survival rate of S globosa conidia and yeast cells significantly decreased following incubation with 1.19M ALA and 162 J/cm2 irradiation in vitro. Melanin was not only capable of protecting the conidia against ALA-PDT, but also against ALA or irradiation alone. After induction by ALA-PDT, alterations in reactive oxygen species generation, DNA damage and ultrastructural changes were observed. CONCLUSIONS: ALA-PDT inhibits the survival of S globosa conidia in vitro and therefore has potential for the treatment of sporotrichosis.


Assuntos
Ácido Aminolevulínico/farmacologia , Antifúngicos/farmacologia , Fotoquimioterapia , Sporothrix/efeitos dos fármacos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pele/microbiologia , Pele/patologia , Esporos Fúngicos/efeitos dos fármacos , Sporothrix/isolamento & purificação , Sporothrix/patogenicidade , Esporotricose/tratamento farmacológico , Esporotricose/microbiologia
7.
Fungal Genet Biol ; 140: 103397, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32325170

RESUMO

Microbial interactions may impact patient's diagnosis, prognosis and treatment. Sporotrichosis is a hyperendemic neglected zoonosis in Brazil, caused by Sporothrix brasiliensis. Four pairs of clinical isolates of Sporothrix were recovered from four diseased cats (CIM01-CIM04, two isolates per animal) raising the possibility of coinfection in a sporotrichosis hyperendemic area, Brazil. Each isolate of the pair had distinct pigmentation in mycological culture, and was designated as "Light" or "Dark", for low and high pigmentation, respectively. Dark isolates reacted strongly with monoclonal antibodies to melanin (p ≤ 0.05) by both ELISA and FACS quantitation, and displayed a ring pattern with some regions exhibiting higher punctuated labeling at cell wall by immunofluorescence. In turn, Light isolates reacted less intensely, with few and discrete punctuated labeling at the cell wall. PCR identified all isolates as S. brasiliensis, MAT1-2 idiomorph. Sequencing of ß-tubulin and calmodulin genes followed by phylogenetic analysis placed all eight isolates within the same cluster as others from the Brazilian hyperendemic area. The ability of these strains to stimulate cytokine production by human PBMCs (Peripheral blood mononuclear cells) was also analyzed. CIM01 and CIM03 Light and Dark isolates showed similar cytokine profiles to the control strain, while CIM02 and CIM04 behaved differently (p < 0.001), suggesting that differences in the surface of the isolates can influence host-fungus interaction. MICs for amphotericin B, terbinafine, caspofungin, micafungin, itraconazole, fluconazole, and voriconazole were obtained (CLSI M38-A2/M27-A3). Pairwise comparisons showed distinct MICs between Sporothrix Light and Dark isolates, higher than at least two-fold dilutions, to at least one of the antifungals tested. Isolates from the same pair displayed discrepancies in relation to fungistatic or fungicidal drug activity, notably after itraconazole exposure. Since S. brasiliensis Light and Dark isolates show disparate phenotypic parameters it is quite possible that coinfection represents a common occurrence in the hyperendemic area, with potential clinical implications on feline sporotrichosis dynamics. Alternatively, future studies will address if this specie may have, as reported for other fungi, broad phenotypic plasticity.


Assuntos
Coinfecção/microbiologia , Sporothrix/genética , Esporotricose/microbiologia , Animais , Brasil/epidemiologia , Gatos , Coinfecção/genética , Coinfecção/veterinária , Doenças Endêmicas/prevenção & controle , Doenças Endêmicas/veterinária , Leucócitos Mononucleares/microbiologia , Testes de Sensibilidade Microbiana , Filogenia , Sporothrix/classificação , Sporothrix/isolamento & purificação , Sporothrix/patogenicidade , Esporotricose/epidemiologia , Esporotricose/genética , Esporotricose/veterinária
8.
Mycopathologia ; 185(5): 813-842, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32052359

RESUMO

Sporotrichosis is a neglected subcutaneous mycosis of humans and animals acquired by traumatic inoculation of soil and plant material (classical route) contaminated with infectious propagules of the pathogen or being bitten/scratched by infected cats (alternative route). Within a genus composed of 53 species displaying an essentially environmental core, there are only a few members which have considerable impacts on human or animal health. Infections are typically caused by S. brasiliensis, S. schenckii or S. globosa. Rare mammal pathogens include members of the S. pallida and S. stenocereus complexes. To illustrate the tremendous impact of emerging zoonotic sporotrichosis on public health, we discuss the main features of the expanding epidemics driven by S. brasiliensis in cats and humans. The cat entry in the transmission chain of sporotrichosis, causing epizooties (cat-cat) or zoonosis (cat-human), has contributed to the definition of new paradigms in Sporothrix transmission, reaching epidemic levels, making the disease a serious public health problem. Indeed, S. brasiliensis infection in humans and animals is likely to become even more important in the future, with projections of its expansion in biogeographic domains and host range, as well as greater virulence in mammals. Therefore, lessons from a long-standing outbreak in the state of Rio de Janeiro about the source and distribution of the etiological agents among outbreak areas can be used to create better control and prevention plans and increase awareness of sporotrichosis as a serious emerging zoonotic disease.


Assuntos
Sporothrix , Esporotricose , Animais , Brasil/epidemiologia , Doenças do Gato/microbiologia , Gatos , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Transmissíveis Emergentes/veterinária , Dermatomicoses/epidemiologia , Dermatomicoses/prevenção & controle , Dermatomicoses/veterinária , Surtos de Doenças/veterinária , Humanos , Controle de Infecções , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/prevenção & controle , Doenças Negligenciadas/veterinária , Sporothrix/classificação , Sporothrix/isolamento & purificação , Sporothrix/patogenicidade , Esporotricose/epidemiologia , Esporotricose/prevenção & controle , Esporotricose/veterinária , Virulência , Zoonoses/epidemiologia , Zoonoses/prevenção & controle
9.
Mem Inst Oswaldo Cruz ; 114: e190260, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644705

RESUMO

BACKGROUND: Sporotrichosis is a subcutaneous mycosis caused by dimorphic pathogenic fungi belonging to the Sporothrix genus. Pathogenic Sporothrix species typically produce melanin, which is known to be a virulence factor. OBJECTIVES: The aim of this study was to perform phenotypic, genotypic, and virulence analyses of two distinct Sporothrix brasiliensis strains isolated from the same lesion on a patient from Rio de Janeiro. METHODS AND FINDINGS: Genotypic analyses by partial sequencing of the calmodulin, ß-tubulin, and chitin synthase genes, as well as polymerase chain reaction (PCR)-fingerprinting by T3B, M13, and GACA, showed that the isolates were very similar but not identical. Both isolates had similar phenotypic characteristics and effectively produced melanin in their yeast forms, accounting for their ability of causing disease in a murine sporotrichosis model. Remarkably, isolate B was albino in its environmental form but caused more severe disease than the pigmented A isolate. CONCLUSIONS: These findings indicate that the patient was infected by two genetically and biologically distinct S. brasiliensis that vary in their production of melanin in their environmental forms. The results underscore the importance of characterizing phenotypically different isolates found in the same clinical specimen or patient.


Assuntos
Antifúngicos/farmacologia , Sporothrix/patogenicidade , Esporotricose/patologia , Esporotricose/virologia , Animais , Impressões Digitais de DNA , Modelos Animais de Doenças , Genótipo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Fenótipo , Reação em Cadeia da Polimerase , Sporothrix/efeitos dos fármacos , Sporothrix/genética , Virulência
11.
Mem. Inst. Oswaldo Cruz ; 114: e190260, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1040612

RESUMO

BACKGROUND Sporotrichosis is a subcutaneous mycosis caused by dimorphic pathogenic fungi belonging to the Sporothrix genus. Pathogenic Sporothrix species typically produce melanin, which is known to be a virulence factor. OBJECTIVES The aim of this study was to perform phenotypic, genotypic, and virulence analyses of two distinct Sporothrix brasiliensis strains isolated from the same lesion on a patient from Rio de Janeiro. METHODS AND FINDINGS Genotypic analyses by partial sequencing of the calmodulin, β-tubulin, and chitin synthase genes, as well as polymerase chain reaction (PCR)-fingerprinting by T3B, M13, and GACA, showed that the isolates were very similar but not identical. Both isolates had similar phenotypic characteristics and effectively produced melanin in their yeast forms, accounting for their ability of causing disease in a murine sporotrichosis model. Remarkably, isolate B was albino in its environmental form but caused more severe disease than the pigmented A isolate. CONCLUSIONS These findings indicate that the patient was infected by two genetically and biologically distinct S. brasiliensis that vary in their production of melanin in their environmental forms. The results underscore the importance of characterizing phenotypically different isolates found in the same clinical specimen or patient.


Assuntos
Humanos , Animais , Camundongos , Esporotricose/patologia , Esporotricose/virologia , Sporothrix/patogenicidade , Antifúngicos/farmacologia , Fenótipo , Sporothrix/efeitos dos fármacos , Sporothrix/genética , Virulência , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Impressões Digitais de DNA , Modelos Animais de Doenças , Genótipo , Camundongos Endogâmicos BALB C
12.
Fungal Biol ; 122(12): 1163-1170, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30449354

RESUMO

Little is known about the differences in the CD4+ T-cell response induced by Sporothrix schenckii and Sporothrix brasiliensis, the most virulent species that cause sporotrichosis. Here, the helper (Th) and regulatory T cells (Tregs) responses were evaluated comparatively in a murine model of sporotrichosis on days 7, 21 and 35 after subcutaneous infection with either S. schenckii or S. brasiliensis conidia. The fungal load was measured at the site of infection, as well as in the liver and spleen. The Th1/Th17/Tregs responses were analyzed in the spleen, while the level of IL-2, IL-4, IL-6, TNF-alpha, IFN-É£, IL-17A and IL-10 cytokines were measured at the local site of infection on 24 h postinfections and in sera on the indicated days. S. brasiliensis caused a longer-lasting infection in the skin and chronic systemic dissemination associated to more severe granulomatous lesions. Similar Th1/Th1-Th17/Tregs responses were induced by both S. brasiliensis and S. schenckii on 7th and 21st d.p.i but on 35 d.p.i a reduction of Th1 and Th1-Th17 cells, associated to higher values of Th17/Tregs cells was observed only in S. brasiliensis-infected mice. In summary, S. brasiliensis caused a more severe disease associated with sustained Th17/Tregs responses than S. schenckii in mice.


Assuntos
Sporothrix/imunologia , Sporothrix/patogenicidade , Esporotricose/patologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Contagem de Colônia Microbiana , Citocinas/análise , Modelos Animais de Doenças , Granuloma/patologia , Fígado/microbiologia , Camundongos , Pele/patologia , Baço/microbiologia , Células Th1/imunologia , Fatores de Tempo
13.
Fungal Biol ; 122(10): 1023-1030, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30227928

RESUMO

Sporotrichosis is an infection caused by members of the Sporothrix genus, and among them, Sporothrix schenckii is one of the etiological agents. Both, the disease and the causative agent have gained interest in the recent years, because of the report of epidemic outbreaks, and the description of the disease transmission from animals to human beings. Despite the relevance of S. schenckii in the clinical field, there are basic aspects of its biology poorly explored. So far, Agrobacterium tumefaciens-mediated transformation has been reported as an alternative for genetic manipulation of this fungal pathogen. Here, we report the optimization of the transformation method and used this to generate insertional mutants that express the green fluorescent protein in S. schenckii. We obtained five mutant strains that showed mitotic stability and expression of the reporter gene. The strains displayed normal cell wall composition, and a similar ability to interact ex vivo with human monocytes and monocyte-derived macrophages. Moreover, the virulence in larvae of Galleria mellonella was similar to that obtained with the wild-type control strains. These data indicate that these fluorescent mutants with normal ability to interact with the host could be used in bioimaging to track the host-Sporothrix interaction in vivo.


Assuntos
Proteínas de Fluorescência Verde/genética , Interações entre Hospedeiro e Microrganismos , Sporothrix/genética , Sporothrix/patogenicidade , Esporotricose/microbiologia , Agrobacterium tumefaciens/genética , Animais , Parede Celular/ultraestrutura , Humanos , Mutagênese Insercional , Sporothrix/ultraestrutura , Transformação Genética , Virulência
14.
mSphere ; 3(3)2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29898987

RESUMO

Sporothrix brasiliensis is the prevalent agent of a large zoonotic outbreak in Brazil. With the involvement of several thousands of cases, this is the largest cohort of human and animal sporotrichosis on record in the world. Infections are characterized by local cutaneous dissemination in humans without underlying disease. S. brasiliensis has shown a high degree of virulence in a mouse model compared to the remaining Sporothrix species, including the ancestral species, Sporothrix schenckii The present paper investigates a genomic and expressed-proteome comparison of S. brasiliensis to S. schenckii Using bottom-up proteomics, we found 60 proteins exclusively expressed in S. brasiliensis No significant genomic differences were found among the genes coding for this protein set. A comparison with literature data identified nine proteins that are known to be involved in virulence and immune evasion in other species, several of which had not yet been reported for the Sporothrix species analyzed.IMPORTANCE Sporotrichosis is an important disease in Brazil that is caused by fungi of the genus Sporothrix and affects cats and humans. Our work investigated the proteins differentially expressed by S. brasiliensis in order to find out why this species is more virulent and pathogenic than S. schenckii We verified a set of proteins that may be related to immune escape and that can explain the high virulence.


Assuntos
Proteínas Fúngicas/análise , Evasão da Resposta Imune , Sporothrix/patogenicidade , Fatores de Virulência/análise , Proteínas Fúngicas/genética , Genômica , Espectrometria de Massas , Proteoma/análise , Sporothrix/química , Sporothrix/genética , Fatores de Virulência/genética
15.
Antonie Van Leeuwenhoek ; 111(6): 965-979, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29214366

RESUMO

The inflorescences and infructescences of African Protea trees provide habitat for a large diversity of Sporothrix species. Here we describe two additional members, Sporothrix nsini sp. nov. and Sporothrix smangaliso sp. nov., that are associated with the infructescences of various Protea species from grasslands and savannas in the KwaZulu-Natal, North-West, Gauteng and Mpumalanga provinces of South Africa. Their description raises the number of described Protea-associated Sporothrix species to twelve. S. smangaliso sp. nov. is distantly related to other Protea-associated species and, in phylogenies using multiple markers (ITS, beta-tubulin and calmodulin), groups with taxa such as Sporothrix bragantina from Brazil and Sporothrix curviconia from the Ivory Coast. S. nsini sp. nov. resolved as sister to a clade containing four other Protea-associated species within the Sporothrix stenoceras complex. S. nsini sp. nov. was collected from within the same infructescences of Protea caffra that also contained the closely related S. africana and S. protearum. This highlights the need to study and understand the factors that influence host selection and speciation of Sporothrix in this atypical niche.


Assuntos
Proteaceae/microbiologia , Sporothrix/patogenicidade , Pradaria , Filogenia , África do Sul
16.
Mol Med Rep ; 17(1): 721-728, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29115539

RESUMO

Sporothrix schenckii is a pathogenic dimorphic fungus with a global distribution. It grows in a multicellular hyphal form at 25˚C and a unicellular yeast form at 37˚C. The morphological switch from mold to yeast form is obligatory for establishing pathogenicity in S. schenckii. Two­component signaling systems are utilized by eukaryotes to sense and respond to external environmental changes. DRK1is a hybrid histidine kinase, which functions as a global regulator of dimorphism and virulence in Blastomyces dermatitidis and Histoplasma capsulatum. An intracellular soluble hybrid histidine kinase, homologous to DRK1 in B. dermatitidis, has previously been identified in S. schenckii and designated as SsDRK1. In the present study, the function of SsDRK1 was investigated using double stranded RNA interference mediated by Agrobacterium tumefaciens. SsDRK1 was demonstrated to be required for normal asexual development, yeast­phase cell formation, cell wall composition and integrity, melanin synthesis, transcription of the morphogenesis­associated gene Ste20 that is involved in the high osmolarity glycerol/mitogen­activated protein kinase pathway, and pathogenicity of S. schenckii in a murine model of cutaneous infection. Further investigations into the signals SsDRK1 responds to, and the interactions of upstream transmembrane hybrid histidine kinases with SsDRK1, are required to uncover novel targets for anti­fungal therapies.


Assuntos
Histidina Quinase/genética , Sporothrix/patogenicidade , Esporotricose/genética , Agrobacterium tumefaciens , Blastomyces/enzimologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Histoplasma/enzimologia , Humanos , Hifas/enzimologia , Hifas/genética , Hifas/patogenicidade , MAP Quinase Quinase Quinases/genética , Morfogênese/genética , Concentração Osmolar , RNA de Cadeia Dupla/genética , Proteínas de Saccharomyces cerevisiae/genética , Sporothrix/enzimologia , Sporothrix/genética , Esporotricose/enzimologia , Esporotricose/microbiologia
17.
PLoS Negl Trop Dis ; 11(8): e0005903, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28854184

RESUMO

Sporotrichosis is a polymorphic chronic infection of humans and animals classically acquired after traumatic inoculation with soil and plant material contaminated with Sporothrix spp. propagules. An alternative and successful route of transmission is bites and scratches from diseased cats, through which Sporothrix yeasts are inoculated into mammalian tissue. The development of a murine model of subcutaneous sporotrichosis mimicking the alternative route of transmission is essential to understanding disease pathogenesis and the development of novel therapeutic strategies. To explore the impact of horizontal transmission in animals (e.g., cat-cat) and zoonotic transmission on Sporothrix fitness, the left hind footpads of BALB/c mice were inoculated with 5×106 yeasts (n = 11 S. brasiliensis, n = 2 S. schenckii, or n = 1 S. globosa). Twenty days post-infection, our model reproduced both the pathophysiology and symptomology of sporotrichosis with suppurating subcutaneous nodules that progressed proximally along lymphatic channels. Across the main pathogenic members of the S. schenckii clade, S. brasiliensis was usually more virulent than S. schenckii and S. globosa. However, the virulence in S. brasiliensis was strain-dependent, and we demonstrated that highly virulent isolates disseminate from the left hind footpad to the liver, spleen, kidneys, lungs, heart, and brain of infected animals, inducing significant and chronic weight loss (losing up to 15% of their body weight). The weight loss correlated with host death between 2 and 16 weeks post-infection. Histopathological features included necrosis, suppurative inflammation, and polymorphonuclear and mononuclear inflammatory infiltrates. Immunoblot using specific antisera and homologous exoantigen investigated the humoral response. Antigenic profiles were isolate-specific, supporting the hypothesis that different Sporothrix species can elicit a heterogeneous humoral response over time, but cross reaction was observed between S. brasiliensis and S. schenckii proteomes. Despite great diversity in the immunoblot profiles, antibodies were mainly derived against 3-carboxymuconate cyclase, a glycoprotein oscillating between 60 and 70 kDa (gp60-gp70) and a 100-kDa molecule in nearly 100% of the assays. Thus, our data broaden the current view of virulence and immunogenicity in the Sporothrix-sporotrichosis system, substantially expanding the possibilities for comparative genomic with isolates bearing divergent virulence traits and helping uncover the molecular mechanisms and evolutionary pressures underpinning the emergence of Sporothrix virulence.


Assuntos
Sporothrix/imunologia , Sporothrix/patogenicidade , Esporotricose/imunologia , Esporotricose/patologia , Estruturas Animais/microbiologia , Estruturas Animais/patologia , Animais , Anticorpos Antifúngicos/sangue , Antígenos de Fungos/imunologia , Peso Corporal , Modelos Animais de Doenças , Histocitoquímica , Immunoblotting , Camundongos Endogâmicos BALB C , Análise de Sobrevida , Fatores de Tempo , Virulência
18.
Microb Pathog ; 110: 78-84, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28645771

RESUMO

The available information about the role of Dectin-1 in sporotrichosis is scarce. Hence, we aimed to assess Dectin-1 expression by macrophages and the activation of some related antifungal mechanisms during the Sporothrix schenckii sensu stricto infection as a first attempt to elucidate the role of this receptor in sporotrichosis. Balb/c mice were intraperitoneally infected with S. schenckii sensu stricto yeast ATCC 16345 and euthanized on days 5, 10 and 15 post-infection, when the following parameters were evaluated: fungal burden in spleen, Dectin-1 expression and nitric oxide (NO) production by peritoneal macrophages, as well as IL-1ß, TNF-α and IL-10 ex vivo secretion by these same cells. Peritoneal macrophages were ex vivo challenged with either the alkali-insoluble fraction (F1) extracted from the S. schenckii cell wall, a commercially available purified ß-1,3-glucan or whole heat-killed S. schenckii yeasts (HKss). Additionally, a Dectin-1 antibody-mediated blockade assay was performed on day 10 post-infection to assess the participation of this receptor in cytokine secretion. Our results showed that Dectin-1 expression by peritoneal macrophages was augmented on days 10 and 15 post-infection alongside elevated NO production and ex vivo secretion of IL-10, TNF-α and IL-1ß. The antibody-mediated blockade of Dectin-1 inhibited cytokine production in both infected and non-infected mice, mainly after ß-1,3-glucan stimulation. Our results suggest a role for Dectin-1 in triggering the immune response during S. schenckii infection.


Assuntos
Antifúngicos/farmacologia , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Sporothrix/efeitos dos fármacos , Sporothrix/patogenicidade , Esporotricose/imunologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Lectinas Tipo C/imunologia , Macrófagos/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Baço/microbiologia , Esporotricose/microbiologia , Fator de Necrose Tumoral alfa/metabolismo
19.
Intern Med ; 56(10): 1243-1246, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28502945

RESUMO

A 72-year-old man presented with persistent oligoarthritis and positive results for rheumatoid factor and was suspected of having rheumatoid arthritis (RA). However, the musculoskeletal ultrasonography (MSUS) findings were not consistent with those of typical RA. He had undergone surgery for carpal tunnel syndrome, which allowed both histopathological and microbiological examinations to be performed. A synovial tissue culture was positive for Sporothrix schenckii, and he was diagnosed with sporotrichal tenosynovitis. He received anti-fungal therapy, and the sporotrichal tenosynovitis resolved. This case suggests that MSUS is a useful modality, and sporotrichal tenosynovitis, though rare, should be considered in the differential diagnosis of RA.


Assuntos
Sistema Musculoesquelético/diagnóstico por imagem , Iodeto de Potássio/uso terapêutico , Sporothrix/patogenicidade , Esporotricose/complicações , Esporotricose/tratamento farmacológico , Tenossinovite/diagnóstico , Tenossinovite/etiologia , Idoso , Humanos , Masculino , Sistema Musculoesquelético/microbiologia , Esporotricose/microbiologia , Tenossinovite/microbiologia , Resultado do Tratamento , Ultrassonografia
20.
J Med Microbiol ; 66(5): 560-569, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28327256

RESUMO

PURPOSE: The aim of the study was to evaluate the main sources and epidemiological patterns and speculate on the evolutionary origin of Sporothrix globosa in Asia. METHODOLOGY: Case and case series literature on sporotrichosis in Asia from January 2007 onwards were reviewed using meta-analysis. Phylogenetic analysis of relevant S. globosa was carried out on the basis of concatenated sequences of ITS, TEF3 and CAL. A haplotype network of CAL sequences of 281 Sporothrix isolates was analysed to determine the population structure of S. globosa. RESULTS: Nearly all cases of sporotrichosis caused by S. globosa in Asia were human. In contrast to the remaining pathogenic Sporothrix species, feline transmission was exceptional; nearly all regional cat-associated cases were caused by Sporothrix schenckii. While the latter species was highly variable and showed recombination, S. globosa seemed to be a clonal offshoot, as was Sporothrix brasiliensis. The origin of the segregants was located in an area of high variability in S. schenckii with a relatively high frequency of Asian strains. CONCLUSION: In Asia, S. globosa was the prevalent species. The low diversity of S. globosa suggested a recent divergence with a founder effect of low variability from the variable ancestral species, S. schenckii.


Assuntos
Sporothrix/genética , Esporotricose/epidemiologia , Esporotricose/microbiologia , Animais , Ásia/epidemiologia , Proteínas de Bactérias/genética , Calmodulina/genética , Doenças do Gato , Gatos , Evolução Molecular , Variação Genética , Humanos , Filogenia , Sporothrix/isolamento & purificação , Sporothrix/patogenicidade , Sporothrix/ultraestrutura , Esporotricose/transmissão , Esporotricose/veterinária
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