RESUMO
We evaluated the growth and the susceptibility to oxidative stress of Sporothrix spp., exposed to different iron concentrations in culture medium, and the susceptibility of Sporothrix spp. to itraconazole, alone and in combination with to the iron chelator deferasirox. The results showed that the growth of S. brasiliensis isolates was more affected by iron availability in comparison to S. schenckii, but both fungal species conidia became more prone to oxidative stress when iron was added to culture medium. Conversely, the combination of itraconazole and deferasirox only resulted in synergism against a minority of S. schenckii isolates.
Assuntos
Antifúngicos/farmacologia , Ferro/farmacologia , Itraconazol/farmacologia , Sporothrix/efeitos dos fármacos , Sporothrix/crescimento & desenvolvimento , Meios de Cultura/química , Deferasirox/farmacologia , Sinergismo Farmacológico , Ferro/metabolismo , Testes de Sensibilidade Microbiana , Esporos Fúngicos/efeitos dos fármacos , Sporothrix/metabolismo , Esporotricose/tratamento farmacológico , Esporotricose/microbiologiaRESUMO
Histopathological studies of human sporotrichosis lesions show pyogenic and granulomatous processes in which polymorphonuclear neutrophils (PMNs) play a central role. Few studies regarding the events associated with the interaction of human PMNs with Sporothrix schenckii have been made despite their importance in the clinical manifestations of the disease. In this study, human PMNs were co-cultured with conidia or yeast cells of S. schenckii to compare the phagocytic activity and morphological changes that could provide a clearer insight into the role of these phagocytes in the initial phase of sporotrichosis. PMNs showed increased cell size and separation of the nuclear lobes after phagocytosis. Through Scanning Electron Microscopy (SEM) analysis, an increase in cells with flattened filaments and vesicles on their surface was observed. Phagocytosed conidia showed a significant increase in width and size. The phagocytic activity was greater against yeasts than with conidia, but the viability of both S. schenckii cellular morphotypes was not drastically affected even after 2â¯h of co-culture. In conclusion, morphological changes in PMNs suggest that S. schenckii induces processes that may favor proinflammatory events. These phagocytes show a high ability to bind or ingest S. schenckii cells without affecting their viability. Morphological changes recorded in ingested conidia, suggest that this fungus could make the dimorphic switching in PMNs.
Assuntos
Neutrófilos/citologia , Neutrófilos/microbiologia , Fagocitose , Sporothrix/imunologia , Tamanho Celular , Células Cultivadas , Técnicas de Cocultura , Voluntários Saudáveis , Humanos , Microscopia Eletrônica de Varredura , Neutrófilos/imunologia , Sporothrix/crescimento & desenvolvimentoRESUMO
A esporotricose é uma doença crônica que envolve o tecido subcutâneo afetando seres humanos e animais, causada pelo fungo termodimórfico Sporothrix spp.. A esporotricose é endêmica na América latina, principalmente no Brasil que teve o maior surto zoonótico já registrado, ocorrendo na cidade do Rio de Janeiro. A espécie Sporothrix brasiliensis é a mais diagnosticada no surto e a mais virulenta entre as especies de Sporothrix spp., causando formas mais graves da doença. A esporotricose em gatos é endêmica, fatal e um dos principais fatores pelo alto número de casos no Rio de Janeiro. O tratamento é longo e não vem sendo o suficiente para conter o número de casos da doença. Uma vacina contra a esporotricose poderia mudar esse paradigma no Brasil. O presente trabalho obteve o proteoma da cepa S. brasiliensis 5110 por meio de uma eletroforese 2D, e caracterizou e identificou as possíveis proteínas imunogênicas do fungo por espectrometria de massa. Por meio de programas de predição, foi avaliado e sintetizado 7 sequências de aminoácidos,das proteínas identificadas com maiores chances de se acoplar a molécula MHC de classe II. Apenas 3 foram capazes de induzir proliferação in vitro, os peptídeos ZR3, ZR4 e ZR8, que foram utilizados como vacina na esporotricose subcutânea e avaliados sua eficácia por meio da carga fúngica, diâmetro das lesões, perfil celular e níveis de citocinas. Neste trabalho concluímos que o peptídeo ZR8 foi o melhor candidato à vacina na esporotricose, pois foi capaz de diminuir o diâmetro das lesões, aumentar os níveis de citocinas protetoras (IFN-γ, IL-17A e IL-1ß) e aumentar o número de células TCD4+ e CD3-/CD19+, sendo assim induzindo uma resposta imunológica protetora na esporotricose subcutânea
Sporotrichosis is a chronic disease, which involves the subcutaneous tissue affecting humans and animals caused by the thermodymorphic fungus Sporothrix spp. Sporotrichosis is endemic in Latin America, mainly in Brazil that had the largest zoonotic outbreak ever recorded, occurring in the city of Rio de Janeiro. The Sporothrix brasiliensis is the species more diagnosed in the outbreak and most virulent, causing severe forms of the disease. Sporotrichosis in cats is endemic, fatal and the main factors due to the high number of cases of the disease in Rio de Janeiro. The treatment is long, and has not been enough to contain the number of cases of sporotrichosis. A vaccine against sporotrichosis could change this paradigm in Brazil. The present work obtained the proteome of S. brasiliensis 5110 strain by 2D electrophoresis, and characterized and identified possible immunogenic proteins by mass spectrometry. By prediction programs were evaluated and synthesized 7 peptide sequence from antigenic proteins that have the highest chances of coupling to the MHC class II molecule. From these 7 peptides only 3 were able to induce proliferation in vitro, called ZR3, ZR4 and ZR8 peptides, that were used as a vaccine in subcutaneous sporotrichosis and evaluated their efficacy through fungal load, lesion diameter, cell profile and cytokine levels. We conclude that ZR8 peptide was the best candidate for sporotrichosis vaccine, since it was able to decrease the lesion diameter, increase the levels of protective cytokines (IFN-γ, IL-17A and IL-1ß) and increase the number of CD4+ T cells and CD3-/CD19+ inducing a protective immune response in subcutaneous sporotrichosis
Assuntos
Animais , Feminino , Camundongos , Peptídeos , Sporothrix/crescimento & desenvolvimento , Vacinas/análise , Espectrometria de Massas/métodos , Esporotricose/prevenção & controle , Proteoma , Eletroforese/instrumentação , MicosesRESUMO
The aim of this study was to evaluate the cholinesterase activity in serum, whole blood, and lymphocytes, as well as to verify its relation to immune response in rats experimentally infected by Sporothrix schenckii. For this study, 63 Wistar rats (Rattus norvegicus), male, adult were divided into three groups: the negative control group (GC: n = 21), the group infected subcutaneously (GSC: n = 21), and the group infected intraperitoneally (GIP: n = 21). The groups were divided into subgroups and the following variables were evaluated at 15, 30, and 40 days post-infection (PI): acetylcholinesterase (AChE) activity in lymphocytes and whole blood, butyrylcholinesterase (BChE) activity in serum, cytokines levels (IL-1, IL-6, TNFα, and INF-γ), immunoglobulins levels (IgA, IgG, IgM, and IgE), and protein profile by electrophoresis. Both infected groups showed increased levels of inflammatory parameters (P < 0.05) in tissue and inflammatory infiltrates. The activities of AChE in lymphocytes and BChE in serum increased (P < 0.05) significantly in animals from the GSC group on day 40 PI compared to the GC group. Regarding the GIP, there was a marked increase in the AChE activity in lymphocytes on days 30 and 40 PI, and in whole blood on days 15, 30, and 40 PI compared to GC. Furthermore, IL-10, an anti-inflammatory cytokine, was also present in high levels during chronic systemic S. schenckii infections in animals. Therefore, it is concluded that cholinesterase has an important modulatory role in the immune response during granulomatous infection by S. schenckii.
Assuntos
Colinesterases/análise , Inflamação/patologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/patologia , Animais , Anticorpos Antifúngicos/sangue , Citocinas/análise , Modelos Animais de Doenças , Linfócitos/enzimologia , Masculino , Proteínas/análise , Ratos Wistar , Soro/enzimologiaRESUMO
Se presenta un caso de onicomicosis de mano, de la cual se aisló en repetidas ocasiones Sporothrix pallida y Trichophyton rubrum. Se discute sobre los principales agentes de onicomicosis, el rol de los hon- gos ambientales y del aislamiento de S.pallida en este y en otro tipo de muestras.
It reports a case of hand onychomycosis, which was isolated repeatedly Sporothrix pallida and Trichophyton rubrum. We discuss the main agents of onychomycosis, the role of the environmental fungi and S.pallida isolation in this and other samples.
Assuntos
Humanos , Idoso , Unhas , Onicomicose , Sporothrix/isolamento & purificação , Sporothrix/crescimento & desenvolvimento , Sporothrix/fisiologia , Sporothrix/patogenicidade , Trichophyton/isolamento & purificação , Trichophyton/crescimento & desenvolvimento , Trichophyton/patogenicidadeRESUMO
BACKGROUND: Adaptive responses in fungi result from the interaction of membrane receptors and extracellular ligands. Many different classes of receptors have been described in eukaryotic cells. Recently a new family of receptors classified as belonging to the progesterone-adiponectin receptor (PAQR) family has been identified. These receptors have the seven transmembrane domains characteristic of G-protein coupled receptors, but their activity has not been associated directly to G proteins. They share sequence similarity to the eubacterial hemolysin III proteins. RESULTS: A new receptor, SsPAQR1 (Sporothrix schenckii progesterone-adiponectinQ receptor1), was identified as interacting with Sporothrix schenckii G protein alpha subunit SSG-2 in a yeast two-hybrid assay. The receptor was identified as a member of the PAQR family. The cDNA sequence revealed a predicted ORF of 1542 bp encoding a 514 amino acids protein with a calculated molecular weight of 57.8 kDa. Protein domain analysis of SsPAQR1 showed the 7 transmembrane domains (TM) characteristic of G protein coupled receptors and the presence of the distinctive motifs that characterize PAQRs. A yeast-based assay specific for PAQRs identified progesterone as the agonist. S. schenckii yeast cells exposed to progesterone (0.50 mM) showed an increase in intracellular levels of 3', 5' cyclic adenosine monophosphate (cAMP) within the first min of incubation with the hormone. Different progesterone concentrations were tested for their effect on the growth of the fungus. Cultures incubated at 35°C did not grow at concentrations of progesterone of 0.05 mM or higher. Cultures incubated at 25°C grew at all concentrations tested (0.01 mM-0.50 mM) with growth decreasing gradually with the increase in progesterone concentration. CONCLUSION: This work describes a receptor associated with a G protein alpha subunit in S. schenckii belonging to the PAQR family. Progesterone was identified as the ligand. Exposure to progesterone increased the levels of cAMP in fungal yeast cells within the first min of incubation suggesting the connection of this receptor to the cAMP signalling pathway. Progesterone inhibited the growth of both the yeast and mycelium forms of the fungus, with the yeast form being the most affected by the hormone.
Assuntos
Progesterona/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Sporothrix/genética , Sporothrix/metabolismo , Sequência de Aminoácidos , Sequência de Bases , AMP Cíclico/metabolismo , DNA Complementar/genética , DNA Fúngico/genética , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Fases de Leitura Aberta , Ligação Proteica , Estrutura Terciária de Proteína , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Progesterona/agonistas , Receptores de Progesterona/química , Transdução de Sinais , Sporothrix/efeitos dos fármacos , Sporothrix/crescimento & desenvolvimento , Temperatura , Técnicas do Sistema de Duplo-HíbridoRESUMO
BACKGROUND: Sporotrichosis caused by the dimorphic fungus Sporothrix schenckii can presents in a variety of clinical forms. Routine diagnosis is made by mycology and serology studies. Few investigations have been focused on the evaluation of the molecular diagnosis. AIM: To determine the value of the nested PCR technique for the diagnosis of experimental sporotrichosis in organs of mice, and to compare the results with the established laboratory diagnostic procedures. METHODS: BALB/c mice were inoculated with growing concentrations of the 2 morphological phases of the fungus. The infected animals were sacrificed one month later and specimens from liver, spleen, lung and testicle were obtained to perform wet mount, culture and molecular diagnosis by the nested PCR technique. Blood samples were obtained for determination of specific antibodies against S. schenckii by the double immunodiffusion procedure. RESULTS: The pathogenicity observed with the different concentrations of the fungus inoculated and its isolation by culture, showed scarce differences in the study of specimens from organs infected with the 2 morphological phases of S. schenckii. Specimens from organs of mice inoculated with the mycelial phase when studied by wet mount and culture, showed a higher positivity (100 and 37.5%) than those from mice inoculated with the yeast phase (73 and 2%). However, diagnosis by the nested PCR molecular technique applied to the latter specimens showed a higher percentage of positivity (75%) and 43% of positive results coming from animals infected with the mycelial phase. Specific antibody detection was positive in 100% all groups of infected mice. CONCLUSIONS: In the study of experimental sporotrichosis in mice, the culture, as well as the antibody detection, was an effective diagnostic procedure, while the nested PCR and microscopic studies had a lower diagnostic value.
Assuntos
DNA Fúngico/análise , Reação em Cadeia da Polimerase/métodos , Sporothrix/isolamento & purificação , Esporotricose/diagnóstico , Animais , Anticorpos Antifúngicos/sangue , Biópsia , Fígado/microbiologia , Pulmão/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Micélio/patogenicidade , Micologia/métodos , Baço/microbiologia , Sporothrix/genética , Sporothrix/crescimento & desenvolvimento , Sporothrix/imunologia , Sporothrix/patogenicidade , Testículo/microbiologia , VirulênciaRESUMO
Sporotrichosis is a subcutaneous mycosis caused by Sporothrix schenckii. Zoonotic transmission to man can occur after scratches or bites of animals, mainly cats. In this study, the gamma radiation effects on yeast of S. schenckii were analyzed with a view of developing a radioattenuated vaccine for veterinary use. The cultures were irradiated at doses ranging from 1.0 to 9.0 kGy. The reproductive capacity was measured by the ability of cells to form colonies. No colonies could be recovered above 8.0 kGy, using inocula up to 10(7) cells. Nevertheless, yeast cells irradiated with 7.0 kGy already were unable to produce infection in immunosuppressed mice. Evaluation by the FungaLight™ Kit (Invitrogen) indicated that yeast cells remained viable up to 9.0 kGy. At 7.0 kGy, protein synthesis, estimated by the incorporation of [L-(35)S] methionine, continues at levels slightly lower than the controls, but a significant decrease was observed at 9.0 kGy. The DNA of 7.0 kGy irradiated cells, analyzed by electrophoresis in agarose gel, was degraded. Cytoplasmic vacuolation was the main change verified in these cells by transmission electron microscopy. The dose of 7.0 kGy was considered satisfactory for yeast attenuation since irradiated cells were unable to produce infection but retained viability, metabolic activity, and morphology.
Assuntos
Raios gama , Sporothrix/efeitos da radiação , Animais , DNA Fúngico/efeitos da radiação , Vacinas Fúngicas/química , Vacinas Fúngicas/efeitos da radiação , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Sporothrix/crescimento & desenvolvimento , Sporothrix/metabolismo , Sporothrix/patogenicidade , Esporotricose/microbiologia , Esporotricose/terapia , Vacinas Atenuadas/química , Vacinas Atenuadas/efeitos da radiaçãoRESUMO
We earlier demonstrated that nitric oxide (NO) is a fungicidal molecule against Sporothrix schenckii in vitro. In the present study we used mice deficient in inducible nitric oxide synthase (iNOS-/-) and C57BL/6 wild-type (WT) mice treated with Nomega-nitro-arginine (Nitro-Arg-treated mice), an NOS inhibitor, both defective in the production of reactive nitrogen intermediates, to investigate the role of endogenous NO during systemic sporotrichosis. When inoculated with yeast cells of S. schenckii, WT mice presented T-cell suppression and high tissue fungal dissemination, succumbing to infection. Furthermore, susceptibility of mice seems to be related to apoptosis and high interleukin-10 and tumour necrosis factor-alpha production by spleen cells. In addition, fungicidal activity and NO production by interferon-gamma (IFN-gamma) and lipopolysaccharide-activated macrophages from WT mice were abolished after fungal infection. Strikingly, iNOS-/- and Nitro-Arg-treated mice presented fungal resistance, controlling fungal load in tissues and restoring T-cell activity, as well as producing high amounts of IFN-gamma Interestingly, macrophages from these groups of mice presented fungicidal activity after in vitro stimulation with higher doses of IFN-gamma. Herein, these results suggest that although NO was an essential mediator to the in vitro killing of S. schenckii by macrophages, the activation of NO system in vivo contributes to the immunosuppression and cytokine balance during early phases of infection with S. schenckii.
Assuntos
Óxido Nítrico/fisiologia , Esporotricose/imunologia , Animais , Apoptose/imunologia , Células Cultivadas , Citocinas/biossíntese , Inibidores Enzimáticos/uso terapêutico , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/imunologia , Interleucina-10/biossíntese , Macrófagos Peritoneais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/deficiência , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/fisiologia , Nitroarginina/uso terapêutico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Baço/imunologia , Sporothrix/crescimento & desenvolvimento , Sporothrix/isolamento & purificação , Esporotricose/tratamento farmacológico , Esporotricose/microbiologia , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/biossínteseRESUMO
Himachal Pradesh, India is a known endemic area for cutaneous sporotrichosis. No attempt has been made to isolate Sporothrix schenckii, the causative fungus, from environmental sources in this region or in India as such. This prospective study was carried out to isolate Sporothrix schenckii from different environmental samples collected from the vicinity of cutaneous sporotrichosis patients. All patients of cutaneous sporotrichosis diagnosed during March 2005-February 2006 were studied. Twenty-one biopsy specimens and 62 environmental samples of soil, various thorns, corn-stalk, grass-blades and sphagnum moss were subjected to mycologic culture on Sabouraud's glucose agar. Sporothrix schenckii was identified by colony characteristics, lacto-phenol cotton blue mounts and demonstration of temperature dimorphism. These patients (F : M 15 : 6) were between 12 and 72 years of age and had cutaneous lesions for 45 days to 4 years. Lymphocutaneous and fixed cutaneous sporotrichosis was seen in 14 (66.6%) and 7 (33.3%) patients respectively. Extremities were involved in 16 (76.2%); and 5 (23.8%) patients had facial lesions. Ten (47.4%) biopsy specimens and six environmental (three soil, three corn-stalk) samples were culture-positive, which showed morphological characteristics suggesting Sporothrix schenckii. No variation in colony characteristics and mycelial morphology was observed in growth isolates from clinical or environmental samples. Temperature dimorphism was observed in all the 10 isolates obtained from the clinical specimens and in two isolates cultured from corn-stalk. Corn-stalks are evidently important sources of Sporothrix schenckii infection although subsequent contamination of wounds appears more important for development of clinical disease. Culture of Sporothrix schenckii from environmental sources may not be always possible to correlate with profile of injuries.
Assuntos
Microbiologia do Solo , Sphagnopsida/microbiologia , Sporothrix/isolamento & purificação , Esporotricose/epidemiologia , Esporotricose/microbiologia , Zea mays/microbiologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Sporothrix/classificação , Sporothrix/crescimento & desenvolvimentoRESUMO
We excised surgically a feline granulomatous lesion and performed histopathological, mycological and molecular examinations. As a result, it was diagnosed as sporotrichosis, which was the second recorded case of a cat so afflicted in Japan. After the operation, we recognized another nodule on the lymph node. Histopathological examination was therefore performed, but no fungi were detected. To prevent recurrence, the cat was administered a antimycotic drug, itraconazole. As a result, no recurrence was found. Excision of the lesion is the treatment of choice for feline sporotrichosis.
Assuntos
Doenças do Gato/microbiologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/veterinária , Zoonoses/microbiologia , Animais , Antifúngicos/uso terapêutico , Doenças do Gato/tratamento farmacológico , Doenças do Gato/cirurgia , Gatos , Membro Posterior/cirurgia , Histocitoquímica/veterinária , Itraconazol/uso terapêutico , Masculino , Esporotricose/tratamento farmacológico , Esporotricose/microbiologia , Esporotricose/cirurgiaRESUMO
We performed a serological study with sera from 92 patients with confirmed sporotrichosis registered between 1999 and 2004 in two hospitals in Rio de Janeiro State, Brazil. The clinical presentation of sporotrichosis was distributed as follows: lymphocutaneous, 67%; fixed cutaneous, 23%; disseminated cutaneous, 8%; and extracutaneous, 2%. Sera were assayed by ELISA against a cell wall antigen of Sporothrix schenckii, SsCBF, that we have previously described. The cross-reactivity was determined with 77 heterologous sera. The serological test showed a sensitivity of 90% and a global efficiency of 86%. A group of 55 patients with several clinical presentations of sporotrichosis was clinically and serologically followed-up for at least 6 months. We observed by ELISA data a decrease in the antibody serum titers which correlated with the progress in healing. An HIV-positive patient with meningeal sporotrichosis was serologically followed-up for over 2 years. Serum and cerebrospinal fluid specimens were examined and significant antibodies levels against the antigen SsCBF were detected. Our results strongly suggest that this serological test is valuable for the differential diagnosis and follow-up of all clinical forms of sporotrichosis.
Assuntos
Antígenos de Fungos/química , Ensaio de Imunoadsorção Enzimática/métodos , Sporothrix/crescimento & desenvolvimento , Esporotricose/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Anticorpos Antifúngicos/sangue , Anticorpos Antifúngicos/líquido cefalorraquidiano , Parede Celular , Glicopeptídeos/química , Infecções por HIV/microbiologia , Humanos , Proteínas de Plantas , Sensibilidade e Especificidade , Esporotricose/sangue , Esporotricose/líquido cefalorraquidianoRESUMO
Sporotrichosis is a chronic granulomatous mycosis caused by the dimorphic fungus Sporothrix schenckii, which is widely distributed in nature, and presents a saprophytic mycelial form on plant debris and soil. The immunological mechanisms involved in the prevention and control of sporotrichosis are not yet fully understood. In this study, mice were studied after infection with Sporothrix schenckii. In the first week after infection, fungal loading increased and thence decreased drastically 14 days after infection. Analysis by immunoblotting showed that the sera of all mice tested had antibodies reacting only with a 70 kDa antigen, with predominance of IgG1 and IgG3. Taken together, our results show that antigens from S. schenckii induced a specific humoral response in infected mice.
Assuntos
Anticorpos Antifúngicos/sangue , Antígenos de Fungos/imunologia , Sporothrix/imunologia , Esporotricose/imunologia , Animais , Antígenos de Fungos/análise , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Feminino , Immunoblotting , Imunoglobulina G/sangue , Fígado/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Baço/microbiologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/microbiologiaRESUMO
The adherence of Sporothrix schenckii yeast cells to several extracellular matrix (ECM) components has already been demonstrated, but the mechanisms of these interactions remained to be defined. In indirect immunofluorescence assays with polyclonal antibodies directed towards the ECM proteins, both hyphae and yeast cells of S. schenckii exhibited the ability to bind laminin and fibronectin. Flow cytometry confirmed the binding of these proteins, and revealed a significant greater binding capability for the yeast cells than for the conidia. Fibronectin and laminin binding was dose-dependent and specific. In addition, competition experiments with synthetic peptides mimicking the adhesive sequences of these proteins, or with cell wall fractions and carbohydrates constitutive of their sugar chains, were performed in order to specify the peptide or carbohydrate motifs involved in the recognition process. A 50% reduction was noticed in fibronectin binding in the presence of the synthetic peptide RGD, and a 38% reduction in laminin binding with the peptide YIGSR. Some carbohydrate-containing fractions of the yeast cell wall also inhibited the binding of fibronectin, but had no significant effect on laminin binding. Together, these results suggest the presence at the yeast surface of distinct receptors for laminin and fibronectin.
Assuntos
Fibronectinas/metabolismo , Laminina/metabolismo , Sporothrix/metabolismo , Adesão Celular , Fibronectinas/química , Citometria de Fluxo , Imunofluorescência , Laminina/química , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Ligação Proteica , Sporothrix/crescimento & desenvolvimento , Sporothrix/fisiologiaRESUMO
We compared the immune defense of mice with chronic granulomatous disease (CGD mice) with that of wild-type C57BL/6 mice for their response to Sporothrix schenckii. A subcutaneous injection of 5 x 10(4) CFU S. schenckii strain IFM41598 into CGD mice resulted in systemic infection and death within 84 days. In contrast, injected C57BL/6 mice did not develop systemic infection and were able to survive through 100 days of observation. Differences in host resistance were analyzed in vitro. Neutrophils and macrophages obtained from CGD mice were found to allow greater growth of this organism than did those obtained from C57BL/6 mice. Moreover, macrophages obtained from immunized CGD mice were able to simply inhibit the growth of this fungus whereas macrophages obtained from immunized C57BL/6 mice killed the fungus within 48 h after phagocytosis. These results suggest that (i) the lack of NADPH oxidase function is a risk factor for lethal S. schenckii infection and (ii) superoxide anion and its reactive oxidative metabolites produced by neutrophils and macrophages are involved in fungistatic and fungicidal activities.
Assuntos
Doença Granulomatosa Crônica/imunologia , Sporothrix/patogenicidade , Esporotricose/imunologia , Animais , Ativação de Macrófagos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Ativação de Neutrófilo , Neutrófilos/imunologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/microbiologiaRESUMO
Morphological differentiation has commanded attention for its putative impact on the pathogenesis of invasive fungal infections. We evaluated in vitro and in vivo the dimorphism from mycelial to yeast-phase of Sporothrix schenckii, Blastomyces dermatitidis and Paracoccidioides brasiliensis isolates, two strains for each species, preserved in mineral oil. S. schenckii strains showed typical micromorphology at 25 degrees C but one strain was unable to complete the dimorphic process in vitro. After in vivo passage through mice the strains had the ability to turn into yeast-like cells and to form colonies on brain-heart infusion medium at 36 degrees C. B. dermatitidis strains grew as dirty white to brownish membranous colonies at 25 degrees C and their micromorphology showed thin filaments with single hyaline conidia. At 36 degrees C the colonies did not differ from those grown at 25 degrees C, but produced a transitional micromorphology. P. brasiliensis strains grew as cream-colored cerebriform colonies at 25 degrees C showing a transitional morphology. B. dermatitidis and P. brasiliensis strains did not turn into yeast-like cells in vivo. The present results demonstrate that B. dermatitidis and P. brasiliensis strains were unable to complete the dimorphic process even after in vivo passage, in contrast to the S. schenckii strain.
Assuntos
Paracoccidioides/citologia , Preservação Biológica/métodos , Sporothrix/citologia , Animais , Meios de Cultura , Estudos de Avaliação como Assunto , Técnicas In Vitro , Camundongos , Óleo Mineral , Micologia/métodos , Paracoccidioides/crescimento & desenvolvimento , Paracoccidioides/isolamento & purificação , Sporothrix/crescimento & desenvolvimento , Sporothrix/isolamento & purificação , Temperatura , VirulênciaRESUMO
Several dimorphic fungi are important human pathogens, but the origin and maintenance of virulence in these organisms is enigmatic, since an interaction with a mammalian host is not a requisite for fungal survival. Recently, Cryptococcus neoformans was shown to interact with macrophages, slime molds, and amoebae in a similar manner, suggesting that fungal pathogenic strategies may arise from environmental interactions with phagocytic microorganisms. In this study, we examined the interactions of three dimorphic fungi with the soil amoeba Acanthameobae castellanii. Yeast forms of Blastomyces dermatitidis, Sporothrix schenckii, and Histoplasma capsulatum were each ingested by amoebae and macrophages, and phagocytosis of yeast cells resulted in amoeba death and fungal growth. H. capsulatum conidia were also cytotoxic to amoebae. For each fungal species, exposure of yeast cells to amoebae resulted in an increase in hyphal cells. Exposure of an avirulent laboratory strain of H. capsulatum to A. castellanii selected for, or induced, a phenotype of H. capsulatum that caused a persistent murine lung infection. These results are consistent with the view that soil amoebae may contribute to the selection and maintenance of certain traits in pathogenic dimorphic fungi that confer on these microbes the capacity for virulence in mammals.
Assuntos
Acanthamoeba/microbiologia , Blastomyces/patogenicidade , Histoplasma/patogenicidade , Sporothrix/patogenicidade , Animais , Blastomyces/crescimento & desenvolvimento , Blastomyces/fisiologia , Linhagem Celular , Feminino , Histoplasma/crescimento & desenvolvimento , Histoplasmose/microbiologia , Histoplasmose/mortalidade , Pneumopatias Fúngicas/microbiologia , Pneumopatias Fúngicas/mortalidade , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Fagocitose , Sporothrix/crescimento & desenvolvimento , VirulênciaRESUMO
A yeast-like fungus isolated from a granulomatous and ulcerative skin lesion in a mongrel cat was mycologically examined. The isolate was identified as Sporothrix schenckii from the morphological findings and its pathogenicity in a mouse, confirming the first case of feline sporotrichosis in Japan. Fortunately, no transmission to humans occurred in this case, however the risk of humans contracting Sporothrix schenckii infection increases with the increase in the number of animals with sporotrichosis. Consequently when handling such animals protective clothing such as gloves should be worn to reduce the risk of transmission of the fungus through open wounds.
Assuntos
Antifúngicos/uso terapêutico , Doenças do Gato , Cetoconazol/uso terapêutico , Sporothrix/isolamento & purificação , Esporotricose/veterinária , Animais , Biópsia , Gatos , Feminino , Granuloma/tratamento farmacológico , Granuloma/patologia , Granuloma/veterinária , Masculino , Camundongos , Ovariectomia , Escroto/microbiologia , Escroto/patologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/tratamento farmacológico , Esporotricose/patologiaRESUMO
A 9-year old male Arabian horse was referred to the Department of Large Animal Surgery of the University of Utrecht because of multiple nodules on the inner side of the right hind leg. The nodules seemed to follow a cutaneolymphatic pattern. Histopathology of a nodule showed a granulomatous inflammation with the presence of multinucleated giant cells. In PAS- and Grocott-stained sections, spheroid yeast-like organisms with some budding were found throughout the tissue. A preliminary diagnosis of sporotrichosis was made. A fresh nodule was cultured and the presence of Sporothrix c.f. schenckii was confirmed. Antifungal therapy was started, which stopped the extension of the granulomata. Sporotrichosis is a rare disease in Europe, but it is quite common in the southern part of the U.S.A.
Assuntos
Doenças dos Cavalos/microbiologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/veterinária , Animais , Doenças dos Cavalos/tratamento farmacológico , Cavalos , Masculino , Iodeto de Sódio/administração & dosagem , Esporotricose/tratamento farmacológico , Esporotricose/microbiologiaRESUMO
Se hace una revisión acerca de la esporotricosis, de acuerdo a la historia natural de la enfermedad y los niveles de prevención. Se hace énfasis en las medidas preventivas para evitar la infección, sobre todo en personas que están en contacto con productos vegetales que pudieran estar contaminados. Se revisan métodos de diagnóstico, tanto de laboratorio como de gabinete, resaltando la importancia a la intradermorreacción de la esporotriquina