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1.
Mycopathologia ; 176(5-6): 345-52, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24005606

RESUMO

Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the fungus Paracoccidioides brasiliensis (S1, PS2, and PS3) and by the new species, P. lutzii. Considering that genetic differences in the Paracoccidioides genus could elicit distinct immune responses by the host, current research investigated serum IgG levels to antigens from P. brasiliensis B339 (S1), P. brasiliensis LDR3 (PS2), and atypical strain LDR2 (P. lutzii), in patients with chronic PCM from the northern and west regions of Paraná, Brazil (n = 35). Cell-free antigen (CFA) and high molecular mass fraction (hMM) were produced from each strain. Samples were analyzed by ELISA and immunodiffusion (ID). ELISA positivity using CFA: B339-100 %, LDR3-83 %, and LDR2-74 %. Response to CFA from B339 was more intense (p < 0.05), while there was no difference between LDR3-LDR2. IgG anti-hMM was higher for antigens from B339 or LDR3, when compared with LDR2 (p < 0.05). There was a positive correlation for each strain between CFA-hMM and for hMM between B339-LDR3 and LDR3-LDR2. ID positivity with CFA: B339-63 %, LDR3-66 %, and LDR2-60 %. We conclude that the intensity of reaction of the patients' sera varies with the strain used; hMM influences tests that use CFA, independently of strain; using ID, positive rates were very similar, but there was a large number of false negative results; ELISA tests using antigens from P. brasiliensis S1 were able to detect a larger number of patients than PS2 and P. lutzii (which had a considerable number of false negative results), and therefore, its use may be more appropriate in this region of Brazil.


Assuntos
Anticorpos Antifúngicos/sangue , Antígenos de Fungos , Imunoglobulina G/sangue , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/microbiologia , Antígenos de Fungos/imunologia , Brasil , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paracoccidioidomicose/diagnóstico , Sensibilidade e Especificidade , Soro/imunologia
2.
Mycopathologia ; 175(3-4): 307-13, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23397251

RESUMO

Paracoccidioidomycosis (PCM) is a disease caused by the Paracoccidioides genus, which includes P. brasiliensis and the new phylogenetic species P. lutzii. Resistance to this infection has been correlated with a Th1 pattern of cellular immune response, while susceptibility is correlated to an intense humoral immune response with an increase in IgE levels. Serum levels of IgE and IgG anti-gp70 and anti-exoantigen in chronic PCM were analyzed by enzyme-linked immunosorbent assay. Results showed a higher gp70 concentration in somatic antigen (SA) than in cell-free antigen (CFA) preparation and significantly higher levels of IgE and IgG anti-gp70 in chronic PCM patients' serum (n = 12) than in normal human serum (n = 12) (p < 0.05). Pearson's correlation analysis showed a strong correlation between IgG and IgE anti-gp70 (r = 0.8424). Additionally, IgE purified from a pool of acute and chronic PCM patient's serum was analyzed by immunoblotting. The patients with the acute form of the disease showed strong bands for gp43 and gp70 in SA but only for gp43 in CFA. In patients with the chronic form, solely the gp43 band was observed. In conclusion, we found that SA is a better source of gp70 than CFA is, and chronic PCM patients show high levels of IgE anti-gp70. This finding suggests that the Th2 immune response is potentially induced by gp70 in PCM disease, which calls for further study.


Assuntos
Anticorpos Antifúngicos/sangue , Imunoglobulina E/sangue , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Antígenos de Fungos/imunologia , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Imunoglobulina G/sangue , Masculino , Soro/imunologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-21598137

RESUMO

An indirect competitive enzyme-linked immunosorbent assay (ELISA) method using a monoclonal antibody for deoxynivalenol (DON) detection in wheat and flour was standardised and validated (detection limit = 177.1 µg kg(-1)) and its performance was compared with LC-MS, quantification limit =140 µg kg(-1)). DON recovery ranged from 88.7% to 122.6% for wheat grain and from 70.6% to 139.3% for flour. Among the 38 wheat samples evaluated, DON was detected in 29 samples (76.3%) by ic-ELISA (281.6-12 291.4 µg kg(-1)) and in 22 samples (57.9%) by LC-MS (155.3-9906.9 µg kg(-1)). The 0.93 correlation coefficient between ic-ELISA and LC-MS data in 19 positive DON wheat samples demonstrated the reliability and efficiency of ic-ELISA. Results indicated that standardised ic-ELISA was suitable for DON screening in wheat samples and the need for continuous monitoring of mycotoxin levels in foodstuffs.


Assuntos
Anticorpos Monoclonais/imunologia , Cromatografia Líquida/métodos , Farinha/análise , Imunoensaio/métodos , Espectrometria de Massas/métodos , Triticum/química , Brasil , Ensaio de Imunoadsorção Enzimática
4.
Mycopathologia ; 171(3): 161-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20835848

RESUMO

Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the fungus Paracoccidioides brasiliensis (Pb). The cyclosporin A (CsA) is an immunosuppressant drug that inhibits calcineurin and has been described as a potential antifungal drug. The present study investigated the effect of CsA on the immune response, fungal load/antigenemia in experimental murine PCM. It was used four groups of BALB/c mice: (a) infected with 1 x 105 Pb18 yeast cells (Pb), (b) infected and treated with CsA every other day 10 mg/kg of CsA (s.c.) during 30 days (Pb/CsA), (c) treated with CsA (CsA) and (d) no infected/treated (PBS). The immune response was evaluated by lymphocyte proliferation, DTH assays to exoAgs, ELISA for IgG anti-gp43 (specific immune responses) and cytokine serum levels (IFN-γ, TNF-α, IL-4 and IL-10). Fungal load was determined by lung colony-forming units (CFU) counts, lung and liver histopathology analysis and antigenemia determined by inhibition-ELISA. As expected, CsA was able to inhibit the specific cellular and humoral immune response (P < 0.05), with decrease in serum IFN-γ, TNF-α and IL-4 levels (P < 0.05). Cyclosporin A treatment also resulted in significantly decreased lung Pb CFU (P < 0.05) as well as a lower number of yeasts in the lung and liver (P < 0.05) by histopathology. In concordance, the decreased antigenemia was observed in Pb/CsA group (P < 0.05). In conclusion, even with immunosuppressive action, treatment with CsA results in decreased lung fungal load/antigenemia in experimental PCM in BALB/c mice. Further study is required to determine whether this represents less severe disease or protection by CsA.


Assuntos
Ciclosporina/uso terapêutico , Pulmão/microbiologia , Paracoccidioides , Paracoccidioidomicose/tratamento farmacológico , Animais , Anticorpos Antifúngicos/sangue , Antígenos de Fungos/sangue , Antígenos de Fungos/imunologia , Contagem de Colônia Microbiana , Ciclosporina/imunologia , Ensaio de Imunoadsorção Enzimática , Proteínas Fúngicas/sangue , Proteínas Fúngicas/imunologia , Glicoproteínas/sangue , Glicoproteínas/imunologia , Hipersensibilidade Tardia/imunologia , Imunoglobulina G/sangue , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-4/sangue , Fígado/microbiologia , Fígado/patologia , Pulmão/patologia , Ativação Linfocitária , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Paracoccidioides/efeitos dos fármacos , Paracoccidioides/crescimento & desenvolvimento , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/microbiologia , Paracoccidioidomicose/patologia , Fator de Necrose Tumoral alfa/sangue
5.
Mycopathologia ; 169(3): 151-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19908162

RESUMO

Histoplasma capsulatum var. capsulatum is a thermally dimorphic fungus that causes histoplasmosis. Fungal hemagglutination activity and cases of reactive hemophagocytic syndrome (RHS) have been reported in the disseminated form of disease. In the present study, soluble components of H. capsulatum var. capsulatum have been investigated for hemagglutinin activity and the capacity to induce hemophagocytosis in the mouse system. To analyze hemagglutinating activity, mouse red blood cells (RBC) (1% v/v in PBS) were incubated (37 degrees C, 1 h) with cell-free antigen (CFAg) from H. capsulatum var. capsulatum (isolate IMT/HC128) (RBC-CFAg) or previously heated CFAg (56 degrees C, 30 min) (RBC-hCFAg) or as control with PBS (RBC-PBS). Hemophagocytosis was analyzed by incubating BALB/c mouse peritoneal phagocytic cells (5 x 10(6) cells) with syngeneic RBC, sensitized or not with CFAg. In addition, mouse polyclonal antibodies were raised against syngeneic RBC-CFAg (anti-RBC-CFAg) and used to analyze CFAg chromatographic fractions (Sephadex G75/120) by immunoenzymatic assay (ELISA). Hemagglutinin activity was observed with RBC-CFAg, but not with RBC-hCFAg or RBC. Also, hemophagocytosis was observed with RBC-CFAg, but not with RBC. The anti-RBC-CFAg antibodies reacted with CFAg fractions corresponding to a molecular mass (MM) higher than 150 kDa. In conclusion, the yeast form of H. capsulatum var. capsulatum releases thermolabile soluble components with hemagglutinin activity and it has been demonstrated for the first time that soluble components of the same fungus induce syngeneic hemophagocytosis in the in vitro mouse system. Also, indirect analysis with antibodies suggests that high-MM components (>150 kDa) are responsible for the interaction with RBC.


Assuntos
Proteínas Fúngicas/imunologia , Proteínas Fúngicas/isolamento & purificação , Hemaglutinação , Histoplasma/química , Fagocitose , Animais , Ensaio de Imunoadsorção Enzimática , Proteínas Fúngicas/química , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular
6.
Braz. j. microbiol ; 40(2): 234-237, Apr.-June 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-520210

RESUMO

The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, a human granulomatous disease. Recently the first case of natural disease in dogs was reported. The complement system is an important effector component of humoral immunity against infectious agents. Therefore, the aim of this study was to evaluate the activation of the dog alternative complement pathway by P. brasiliensis. Initially, the ability of erythrocytes of guinea pig, rabbit, sheep, chicken and swine to activate the dog alternative pathway was evaluated. The guinea pig erythrocytes showed the greatest capacity to activate dog alternative pathway. The alternative (AH50) hemolytic activity was evaluated in 27 serum samples from healthy dogs and the mean values were 87.2 AH50/ml. No significant differences were observed in relation to sex and age. The alternative pathway activation by P. brasiliensis was higher in serum samples from adult dogs when compared to puppies and aged dogs (p < 0.05). This is the first report of dog alternative complement pathway activation by P. brasiliensis and suggests that it may play a protective role in canine paracoccidioidomycosis.


O fungo dimórfico Paracoccidioides brasiliensis é o agente etiológico da paracoccidioidomicose, uma doença granulomatosa humana. Recentemente, foi relatado o primeiro caso da doença natural em cães. O sistema complemento é um importante componente efetor da imunidade humoral contra agentes infecciosos. Portanto, o objetivo deste trabalho foi avaliar a ativação da via alternativa do complemento canina pelo P. brasiliensis. Inicialmente, foi avaliada a capacidade de eritrócitos de cobaia, coelho, carneiro, galinha e suíno ativarem a via alternativa do complemento canino. Os eritrócitos de cobaia apresentaram maior capacidade de ativar a via alternative do complemento canino. A atividade hemolítica da via alternativa (AH50) foi avaliada em 27 amostras de soro de cães saldáveis e os valores médios observados foram de 87,2 AH50/ml. Não foi observada diferença significativa ao sexo e idade. A ativação da via alternativa pelo P. brasiliensis foi maior nas amostras de soro de cães adultos quando comparada aos cães filhotes e idosos (p < 0.05). Este é o primeiro relato da ativação da via alternative do complemento canino pelo fungo P. brasiliensis e sugere que pode ter um papel protetor na paracoccidioidomicose canina.


Assuntos
Animais , Cães , Formação de Anticorpos , Ensaio de Atividade Hemolítica de Complemento , Eritrócitos , Paracoccidioidomicose , Cães , Métodos , Técnicas e Procedimentos Diagnósticos
7.
J Clin Lab Anal ; 23(2): 139-43, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19288448

RESUMO

The fungus Paracoccidioides brasiliensis is the pathogen of paracoccidioidomycosis (PCM), a systemic mycosis prevalent in Latin America. The loop-mediated isothermal amplification method (LAMP) was used in this study to detect the presence of P. brasiliensis in sputa samples from patients with chronic PCM, suspected PCM, and a negative control. The target P. brasiliensis gp43 gene was amplified in less than 4 hr in 11 of 18 sputa samples tested. The LAMP method had the advantage of speed and simplicity compared with the classic diagnostic methods such as the histopathological test or biological material culture and did not require sophisticated technical apparatus. It would be an important aid in cases where immediate treatment would mean patient survival, especially in immune-suppressed patients.


Assuntos
Antígenos de Fungos/genética , Proteínas Fúngicas/genética , Glicoproteínas/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/diagnóstico , Escarro/microbiologia , Adulto , Idoso , Erros de Diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Paracoccidioides/genética , Sensibilidade e Especificidade
8.
Braz J Microbiol ; 40(2): 234-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031350

RESUMO

The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, a human granulomatous disease. Recently the first case of natural disease in dogs was reported. The complement system is an important effector component of humoral immunity against infectious agents. Therefore, the aim of this study was to evaluate the activation of the dog alternative complement pathway by P. brasiliensis. Initially, the ability of erythrocytes of guinea pig, rabbit, sheep, chicken and swine to activate the dog alternative pathway was evaluated. The guinea pig erythrocytes showed the greatest capacity to activate dog alternative pathway. The alternative (AH50) hemolytic activity was evaluated in 27 serum samples from healthy dogs and the mean values were 87.2 AH50/ml. No significant differences were observed in relation to sex and age. The alternative pathway activation by P. brasiliensis was higher in serum samples from adult dogs when compared to puppies and aged dogs (p ≤ 0.05). This is the first report of dog alternative complement pathway activation by P. brasiliensis and suggests that it may play a protective role in canine paracoccidioidomycosis.

9.
Artigo em Inglês | VETINDEX | ID: vti-444371

RESUMO

The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, a human granulomatous disease. Recently the first case of natural disease in dogs was reported. The complement system is an important effector component of humoral immunity against infectious agents. Therefore, the aim of this study was to evaluate the activation of the dog alternative complement pathway by P. brasiliensis. Initially, the ability of erythrocytes of guinea pig, rabbit, sheep, chicken and swine to activate the dog alternative pathway was evaluated. The guinea pig erythrocytes showed the greatest capacity to activate dog alternative pathway. The alternative (AH50) hemolytic activity was evaluated in 27 serum samples from healthy dogs and the mean values were 87.2 AH50/ml. No significant differences were observed in relation to sex and age. The alternative pathway activation by P. brasiliensis was higher in serum samples from adult dogs when compared to puppies and aged dogs (p 0.05). This is the first report of dog alternative complement pathway activation by P. brasiliensis and suggests that it may play a protective role in canine paracoccidioidomycosis.


O fungo dimórfico Paracoccidioides brasiliensis é o agente etiológico da paracoccidioidomicose, uma doença granulomatosa humana. Recentemente, foi relatado o primeiro caso da doença natural em cães. O sistema complemento é um importante componente efetor da imunidade humoral contra agentes infecciosos. Portanto, o objetivo deste trabalho foi avaliar a ativação da via alternativa do complemento canina pelo P. brasiliensis. Inicialmente, foi avaliada a capacidade de eritrócitos de cobaia, coelho, carneiro, galinha e suíno ativarem a via alternativa do complemento canino. Os eritrócitos de cobaia apresentaram maior capacidade de ativar a via alternative do complemento canino. A atividade hemolítica da via alternativa (AH50) foi avaliada em 27 amostras de soro de cães saldáveis e os valores médios observados foram de 87,2 AH50/ml. Não foi observada diferença significativa ao sexo e idade. A ativação da via alternativa pelo P. brasiliensis foi maior nas amostras de soro de cães adultos quando comparada aos cães filhotes e idosos (p 0.05). Este é o primeiro relato da ativação da via alternative do complemento canino pelo fungo P. brasiliensis e sugere que pode ter um papel protetor na paracoccidioidomicose canina.

10.
Mycopathologia ; 165(6): 367-71, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18320347

RESUMO

The aim of this study was to evaluate the humoral immune response in cattle immunized with Paracoccidioides brasiliensis and perform a seroepidemiological study of paracoccidioidomycosis in dairy cattle from Mato Grosso do Sul. Two animals (one steer and one heifer) were inoculated with a suspension of P. brasiliensis in Freund incomplete adjuvant. Blood samples were collected periodically to evaluate humoral immune response by immunodiffusion and ELISA, using exoantigen and gp43 as antigens, respectively. The antibody production was detected by immunodiffusion and ELISA, in both animals, 14 days after immunization. The soroepidemiologic study was carried out in 400 cattle of Mato Grosso do Sul from four municipalities: Corumbá, Dourados, Nova Andradina, and São Gabriel d'Oeste. The municipalities of Corumbá (30%) and Nova Andradina (28%) showed higher positivity than Dourados (8%) and São Gabriel d'Oeste (4%). In this study we concluded that cattle immunized with P. brasiliensis develop humoral immune response for gp43, remaining with high titers of antibodies, and that this animal species could be an epidemiologic marker of paracoccidioidomycosis.


Assuntos
Anticorpos Antifúngicos/sangue , Antígenos de Fungos/imunologia , Proteínas Fúngicas/imunologia , Glicoproteínas/imunologia , Paracoccidioides/imunologia , Paracoccidioidomicose/epidemiologia , Paracoccidioidomicose/veterinária , Animais , Bovinos , Ensaio de Imunoadsorção Enzimática , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/patologia , Estudos Soroepidemiológicos
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