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1.
Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, a systemic mycosis that affects mainly rural workers in Brazil and other Latin American countries. The participation of domestic and wild animal species in the ecoepidemiology of paracoccidioidomycosis is not well understood. The objective of this study was to evaluate P. brasiliensis infection in dairy goats. The humoral immune response to the gp43 antigen, the main antigen used for paracoccidioidomycosis serodiagnosis and seroepidemiology, was evaluated in two goats immunized with inactivated P. brasiliensis yeast cells. Both animals produced antibodies against the P. brasiliensis gp43 antigen, detected by ELISA, 2 weeks after immunization. A total of 202 goat serum samples were analyzed by ELISA and the immunodiffusion test using P. brasiliensis gp43 and exoantigen as antigens. The seropositivity observed by ELISA was 26.2 % although no reactivity was detected by immunodiffusion. The animals over 18 months of age showed significantly higher positivity (40 %) than animals aged 6–18 months (14.8 %) and 0–6 months (2.6 %). Taking into account that cross-reactivity may occur with other pathogens, the serum samples were also analyzed by ELISA using Histoplasma capsulatum exoantigen as antigen and the positivity observed was 14.3 %. The low correlation (0.267) observed between reactivity to P. brasiliensis gp43 and H. capsulatum exoantigen suggests co-infection rather than cross-reactivity. This is the first report showing serological evidence of P. brasiliensis infection in goats and reinforces that domestic animals are useful epidemiological markers of paracoccidioidomycosis.  相似文献   

2.
Paracoccidioides brasiliensis is a temperature-dependent dimorphic fungus and the agent of paracoccidioidomycosis (PCM), which is prevalent in rural workers of Latin American countries. Until a decade ago, most of the studies involving P. brasiliensis used clinical isolates, since environmental samples from soil are difficult to obtain. More recently, P. brasiliensis has been isolated from infected wild and domestic animals, especially from the nine-banded armadillo Dasypus novemcinctus in Brazil. Over the years, diversity within the species has been observed at several phenotypic levels. The present review will discuss the reports focusing on genetic polymorphism, which culminated with the detection of P. brasiliensis phylogenetic species as a result of a multilocus study. Polymorphism in the PbGP43 gene is detailed. This gene encodes fungal glycoprotein gp43, a dominant P. brasiliensis antigen largely studied in the last two decades for its importance in diagnosis, immune protection, and adhesive properties to extracellular matrix-associated proteins. Fungal traits associated with genetic groups are discussed.  相似文献   

3.
Epidemiological studies of paracoccidioidomycosis have been based on surveys achieved with intradermal tests, and paracoccidioidin is the most common antigen used in most cases. The glycoprotein of 43-kDa (gp43) has been used in intradermal tests. It is the most antigenic component of Paracoccidioides brasiliensis, and it provides greater specificity to evaluate infection for this fungus. In this study, the prevalence of P. brasiliensis infection was estimated with intradermal tests involving gp43 for 695 people in rural Central-West Brazil. The infection rate was 45.8 % (95 % CI = 42.1–49.5), and the average age of those infected was 45.8 ± 18.2 years. The prevalence did not show gender-based differences but increased with age. The results demonstrate the importance of P. brasiliensis infection in rural settlements and the early exposure of children in the region to the fungus. Despite the high antigenicity and specificity of gp43, its usage must be standardized, so that epidemiological surveys will be comparable and more accurately reflect P. brasiliensis infection in endemic areas.  相似文献   

4.
Glycoprotein gp43 is an immunodominant diagnostic antigen for paracoccidioidomycosis caused by Paracoccidioides brasiliensis. It is abundantly secreted in isolates such as Pb339. It is structurally related to beta-1,3-exoglucanases, however inactive. Its function in fungal biology is unknown, but it elicits humoral, innate and protective cellular immune responses; it binds to extracellular matrix-associated proteins. In this study we applied an antisense RNA (aRNA) technology and Agrobacterium tumefaciens-mediated transformation to generate mitotically stable PbGP43 mutants (PbGP43 aRNA) derived from wild type Pb339 to study its role in P. brasiliensis biology and during infection. Control PbEV was transformed with empty vector. Growth curve, cell vitality and morphology of PbGP43 aRNA mutants were indistinguishable from those of controls. PbGP43 expression was reduced 80–85% in mutants 1 and 2, as determined by real time PCR, correlating with a massive decrease in gp43 expression. This was shown by immunoblotting of culture supernatants revealed with anti-gp43 mouse monoclonal and rabbit polyclonal antibodies, and also by affinity-ligand assays of extracellular molecules with laminin and fibronectin. In vitro, there was significantly increased TNF-α production and reduced yeast recovery when PbGP43 aRNA1 was exposed to IFN-γ-stimulated macrophages, suggesting reduced binding/uptake and/or increased killing. In vivo, fungal burden in lungs of BALB/c mice infected with silenced mutant was negligible and associated with decreased lung ΙΛ−10 and IL-6. Therefore, our results correlated low gp43 expression with lower pathogenicity in mice, but that will be definitely proven when PbGP43 knockouts become available. This is the first study of gp43 using genetically modified P. brasiliensis.  相似文献   

5.
We aimed to evaluate whether the occurrence of cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii, has implications in the immunodiagnosis of paracoccidioidomycosis (PCM). Small quantities of the antigen gp43 were found in culture filtrates of P. lutzii strains and this molecule appeared to be more variable within P. lutzii because the synonymous-nonsynonymous mutation rate was lower, indicating an evolutionary process different from that of the remaining genotypes. The production of gp43 also varied between isolates belonging to the same species, indicating that speciation events are important, but not sufficient to fully explain the diversity in the production of this antigen. The culture filtrate antigen AgEpm83, which was obtained from a PS3 isolate, showed large quantities of gp43 and reactivity by immunodiffusion assays, similar to the standard antigen (AgB-339) from an S1 isolate. Furthermore, AgEpm83 was capable of serologically differentiating five serum samples from patients from the Botucatu and Jundiaí regions. These patients had confirmed PCM but, were non-reactive to the standard antigen, thus demonstrating an alternative for serological diagnosis in regions in which S1 and PS2 occur. We also emphasise that it is not advisable to use a single antigen preparation to diagnose PCM, a disease that is caused by highly diverse pathogens.  相似文献   

6.
There is some evidence that dogs can be naturally infected by Paracoccidioides brasiliensis in endemic areas of paracoccidioidomycosis. In order to evaluate canine infection with this fungus, a survey with 149 urban and 126 rural dogs was carried out using ELISA and intradermal tests with the gp43 antigen of P. brasiliensis in Uberaba, Minas Gerais state of Brazil. Forty-one out of 149 urban dogs were euthanatized and had their lungs, liver and spleen removed. One slice from each viscera was processed for histopathological examination and the remaining was homogenized and then cultivated on mycobiotic agar at room temperature and Fava-Netto medium at 35°C and observed for 12 weeks. Of urban dogs, 75 (50.3%) were small adult females, 56 (36%) were strays, while 93 (64%) had been donated to the municipal zoonosis control center. Nine (6.2%) had a positive intradermal test without statistical differences regarding gender, race, nutritional status or origin. No colonies with microscopic or morphology appearances resembling P. brasiliensis were isolated, nor granulomatous process or fungal structures were observed from histopathological examination. Eighty (53.6%) of the urban dogs presented seroreactivity, without statistical differences regarding gender, race, nutritional state, origin, or positive intradermal test. Of 126 rural dogs, 102 (80.5%) presented antibodies against gp43 antigen, and this was statistically significant in relation to the reactivity detected in urban dogs (P = 0.0001). Thus, dogs are commonly infected with P. brasiliensis, but they probably present natural resistance to develop paracoccidioidomycosis.  相似文献   

7.
The objective of this study was to evaluate the prevalence of antibodies against Paracoccidioides brasiliensis in sheep from Guarapuava, Paraná State, Brazil. The seroepidemiological study was carried out in 262 sheep. The samples were analyzed by ELISA and immunodiffusion test using P. brasiliensis gp43 and exoantigen as antigens, respectively. Initially, two sheep were immunized with P. brasiliensis to evaluate whether contact with the fungal cells could induce a humoral immune response against gp43 and exoantigen from P. brasiliensis. Both animals produced antibodies against gp43 and exoantigen, the main antigens used for diagnosis and seroepidemiology of paracoccidioidomycosis. A reactivity of 37% was observed to the P. brasiliensis gp43 antigen by ELISA although no reactivity had been observed by the immunodiffusion test. Sheep under extensive grazing system showed higher frequency of positivity to P. brasiliensis (P ≤ 0.05) than those under intensive and semi-intensive systems. These data suggest that sheep may be a useful epidemiological marker of P. brasiliensis presence in the environment and reinforce that contact with soil is an important risk factor for infection.  相似文献   

8.
Paracoccidioidomycosis, caused by the thermodimorphic fungus Paracoccidioides brasiliensis, is a human systemic mycosis prevalent in Latin America. Paracoccidioidomycosis affects mainly male rural workers, causing granulomatous lesions in several organs such as the lungs, liver and spleen. The participation of other animal species in the fungus epidemiology is not well understood. The objective of this study was to evaluate the infection of free-range domestic pigs by P. brasiliensis. Serum samples from 106 pigs were analyzed by ELISA and the immunodiffusion test, using P. brasiliensis gp43 and exoantigen as antigens, respectively. The overall positivity to gp43 in ELISA was 37.7 %, although no reactivity was observed in the immunodiffusion test and nor was P. brasiliensis detected in tissue samples (spleen, lung, liver and lymph nodes) from slaughtered animals submitted to culture, histopathological examination and PCR analysis. Five pigs seronegative to gp43 were exposed to natural infection by P. brasiliensis, and all animals seroconverted 3 months after exposure. The results suggest that free-range pigs are frequently infected with P. brasiliensis but are resistant to disease development. This is the first report of paracoccidioidomycosis in pigs.  相似文献   

9.
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.  相似文献   

10.
Distinct glycolipid profiles are described in microorganisms, which have been shown to modulate the innate immune system. We tested the hypothesis that glycosphingolipids from Paracoccidioides brasiliensis have immunomodulatory properties on monocytes and dendritic cells of two groups of healthy individuals, one cured of paracoccidioidomycosis in the past (CUR-I) and the other nonexposed to P. brasiliensis (HNE-I). Two classes of glycosphingolipids purified from yeast cells were evaluated: a neutral glycosphingolipid, monohexosylceramide (CMH), and acidic glycosylinositolphosphorylceramides (GIPCs). Both glycosphingolipids affected the functioning of innate immunity cells, interfering with the antigen presenting process: P. brasiliensis yeast cells phagocytosis, IL-10 secretion, and costimulatory molecules and recognition receptors expression by monocytes were altered, while dendritic cell antigen presentation to autologous T cells was markedly down-modulated as shown by reduced T-cell proliferative responses. The mechanisms by which CMH and GIPCs exert their effects differ since the target cells did not always respond similarly to the challenge with the glycosphingolipids. Moreover, CUR-I and HNE-I presented different responses to the glycosphingolipids. Differences not only in the glycosphingolipid structure (such as the polar head group or the ceramide moiety), but also in the innate immunity properties of CUR-I and HNE-I, may underlie these differences and contribute to individual’s susceptibility or resistance to develop paracoccidioidomycosis.  相似文献   

11.

Background

Paracoccidioides brasiliensis and P. lutzii cause paracoccidioidomycosis (PCM). P. brasiliensis main diagnostic antigen is glycoprotein gp43, and its peptide sequence is 81% identical with a P. lutzii ortholog here called Plp43. P. lutzii (“Pb01-like”) apparently predominates in Midwestern/Northern Brazil, where high percentages of false-negative reactions using P. brasiliensis antigens have recently been reported. The aim of this work was to produce recombinant Plp43 to study its antigenic identity with gp43.

Methodology

We expressed rPlp43 as a secreted major component in Pichia pastoris and studied its reactivity in immunoblot with PCM patients'' sera from Southwestern and Midwestern Brazil.

Principal Findings

We showed that rPlp43 is not glycosylated and bears glucanase activity. The protein did not react with anti-gp43 monoclonal antibodies in immunoblot, suggesting absence of the corresponding gp43 epitopes. Nevertheless, common epitope(s) might exist, considering that gp43-positive PCM sera recognized rPlp43 in immunoblot, while gp43-negative sera (33 out of 51) from patients resident in Midwestern Brazil were also rPlp43-negative. Two genotyped P. lutzii were from patients with gp43-negative sera, suggesting that non-reactive sera are from patients infected with this species.

Conclusion

Our data suggest that gp43 and Plp43 bear one or only a few common epitopes and that gp43 cannot be used in diagnosis of PCM patients infected with P. lutzii probably because Plp43 is poorly expressed during infection.  相似文献   

12.
The objective of the present study was to evaluate infection of cats by Paracoccidioides brasiliensis. Serum samples of 136 cats from rural (n = 86) and urban areas (n = 50) were analyzed by indirect ELISA and immunodiffusion test using P. brasiliensis gp43 and exoantigen as antigens, respectively, and an overall reactivity of 31.6 % was observed by ELISA although no reactivity was detected by immunodiffusion. The positivity observed in animals living in rural areas (48.8 %) with free access to soil was significantly higher (P < 0.0001) than among urban animals (2 %) with limited access to soil, although no significant difference was observed in relation to age or sex. The high rates of positivity observed in cats from rural areas suggest that not diagnosed cases of this mycosis may be occurring in cats living in endemic areas for human paracoccidioidomycosis. This is the first report showing serological evidence of P. brasiliensis infection in cats.  相似文献   

13.
The objective of this study was to detect antibodies against Paracoccidioides brasiliensis in free-range and caged chickens Gallus domesticus. Initially, the humoral immune response of two chickens immunized with P. brasiliensis was evaluated. Both animals showed the production of antibodies to gp43, the major P. brasiliensis antigen. The seroepidemiological survey was conducted in chickens from the Pantanal region in Mato Grosso do Sul State (free-range n = 40) and from northern region of Paraná State (free-range n = 100, caged n = 43). The serum samples were analyzed by indirect ELISA using gp43 as antigen. The positivity observed in free-range chickens from Mato Grosso do Sul (55%) was significantly higher (P = 0.0001) than in free-range chickens from Paraná State (16%). In contrast to the free-range chickens, no positivity was observed in the caged chickens (P = 0.003). This is the first report showing serological evidence of P. brasiliensis infection in chickens. The results suggest that free-range chickens are more frequently infected by P. brasiliensis, probably due to the constant contact with soil than caged chickens and could be useful as epidemiological markers of paracoccidioidomycosis.  相似文献   

14.
An enzyme-linked immunosorbent assay (ELISA) for detection and quantification of antibodies antiParacoccidioides brasiliensis is described. Polystyrene plates have been used as solid phase to absorb P. brasiliensis metabolic yeast phase antigen. Twenty sera of proven paracoccidioidomycosis, 11 of histoplasmosis due Histoplasma capsulatum, 20 of aspergillosis and 20 human normal sera were tested. Ninety-five percent of the paracoccidioidomycosis sera had O.D. superior to 0.150 (from 0.163 to 2.650) at 1/400 serum dilution. ELISA assay was compared with counterimmunoelectrophoresis and erythro-immunoassay tests; a correlation was observed only with erythro-immunoassay. ELISA test should give new perspectives for the serodiagnosis of paracoccidioidomycosis.  相似文献   

15.
Paracoccidioides lutzii is a new agent of paracoccidioidomycosis (PCM) and has its epicenter localized to the Central-West region of Brazil. Serological diagnosis of PCM caused by P. lutzii has not been established. This study aimed to develop new antigenic preparations from P. lutzii and to apply them in serological techniques to improve the diagnosis of PCM due to P. lutzii. Paracoccidioides lutzii exoantigens, cell free antigen (CFA), and a TCA-precipitated antigen were evaluated in immunodiffusion (ID) tests using a total of 89 patient sera from the Central-West region of Brazil. Seventy-two sera were defined as reactive for P. brasiliensis using traditional antigens (AgPbB339 and gp43). Non-reactive sera for traditional antigens (n = 17) were tested with different P. lutzii preparations and P. lutzii CFA showed 100% reactivity. ELISA was found to be a very useful test to titer anti-P. lutzii antibodies using P. lutzii-CFA preparations. Sera from patients with PCM due to P. lutzii presented with higher antibody titers than PCM due to P. brasiliensis and heterologous sera. In western blot, sera from patients with PCM due to P. lutzii were able to recognize antigenic molecules from the P. lutzii-CFA antigen, but sera from patients with PCM due to P. brasiliensis could not recognize any P. lutzii molecules. Due to the facility of preparing P. lutzii CFA antigens we recommend its use in immunodiffusion tests for the diagnosis of PCM due to P. lutzii. ELISA and western blot can be used as complementary tests.  相似文献   

16.
Paracoccidioides brasiliensis rarely shows bone marrow involvement and its response to treatment with itraconazole in children needs further assessment. We describe here a child with a juvenile disseminated form of paracoccidioidomycosis, which showed reticuloendothelial system involvement and the presence of Paracoccidioides brasiliensis in the bone marrow. The patient showed an effective and rapid response to itraconazole therapy.  相似文献   

17.
Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis, the most prevalent systemic mycosis in Latin America. The morbidity and mortality associated with paracoccidioidomycosis necessitate our understanding of fungal pathogenesis and discovering of new agents to treat this infection. Animal models have contributed much to the knowledge of fungal infections and their corresponding therapeutic treatments. This is true for animal models of the primary fungal pathogens such as P. brasiliensis. This review describes the development, details and utility of animal models of paracoccidioidomycosis for studying and developing the current antifungal agents used for therapy of this fungal disease and novel agents with antifungal properties against P. brasiliensis.  相似文献   

18.

Paracoccidioidomycosis is a systemic mycosis prevalent in Latin American countries, caused by the dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. The habitat of these fungi in nature remains undefined, although it is believed that infection occurs by inhalation of infective propagules present in soil. Sentinel animals, such as dogs, can be valuable epidemiological markers of paracoccidioidomycosis. Taking into account that paracoccidioidomycosis and visceral leishmaniasis may occur in the same area, the objective of this study was to evaluate the occurrence of P. brasiliensis infection in dogs positive for Leishmania sp. Serum samples of dogs positive (n = 199) and negative (n = 101) for Leishmania sp. were analyzed by the immunodiffusion test using P. brasiliensis exoantigen, and 22 samples (7.3%) were positive. The serum samples positive in the immunodiffusion test were also analyzed by Western blotting using the P. brasiliensis gp43 recombinant protein, and 86% of the samples were positive. A high positive correlation (r = 0.96) between positivity for Leishmania sp. and P. brasiliensis was observed. These data suggest an association between leishmaniasis and paracoccidioidomycosis in dogs.

  相似文献   

19.
Chemotherapy is the basis of treatment of paracoccidioidomycosis in its various forms. Depending on the Paracoccidioides brasiliensis virulence, the status of host immunity, the degree of tissue involvement and fungal dissemination, treatment can be extended for long periods with an alarming frequency of relapses. Association of chemotherapy with a vaccine to boost the cellular immune response seemed a relevant project not only to reduce the time of treatment but also to prevent relapses and improve the prognosis of anergic cases. The candidate immunogen is the gp43 major diagnostic antigen of P.␣brasiliensis and more specifically its derived peptide P10, carrying the CD4+ T-cell epitope. Both gp43 and P10 protected Balb/c mice against intratracheal infections with virulent P. brasiliensis strain. P10 as single peptide or in a multiple-antigen-peptide (MAP) tetravalent construction was protective without adjuvant either by preimmunization and intratracheal challenge or as a therapeutic agent in mice with installed infection. P10 showed additive protective effects in drug-treated mice stimulating a Th-1 type immune response with high IFN-γ and IL-12. P10 and few other peptides in the gp43 were selected by Tepitope algorithm and actually shown to promiscuously bind several prominent HLA-DR molecules suggesting that a peptide vaccine could be devised for a genetically heterogenous population. P10 was protective in animals turned anergic, was effective in a DNA minigene vaccine, and increased the protection by monoclonal antibodies in Balb/c mice. DNA vaccines and peptide vaccines are promising therapeutic tools to be explored in the control of systemic mycoses.  相似文献   

20.

Background

Paracoccidioides brasiliensis (Eukaryota, Fungi, Ascomycota) is a thermodimorphic fungus, the etiological agent of paracoccidioidomycosis, the most important systemic mycoses in Latin America. Three isolates corresponding to distinct phylogenetic lineages of the Paracoccidioides species complex had their genomes sequenced. In this study the identification and characterization of class II transposable elements in the genomes of these fungi was carried out.

Results

A genomic survey for DNA transposons in the sequence assemblies of Paracoccidioides, a genus recently proposed to encompass species P. brasiliensis (harboring phylogenetic lineages S1, PS2, PS3) and P. lutzii (Pb01-like isolates), has been completed. Eight new Tc1/mariner families, referred to as Trem (Tr ansposable e lement m ariner), labeled A through H were identified. Elements from each family have 65-80% sequence similarity with other Tc1/mariner elements. They are flanked by 2-bp TA target site duplications and different termini. Encoded DDD-transposases, some of which have complete ORFs, indicated that they could be functionally active. The distribution of Trem elements varied between the genomic sequences characterized as belonging to P. brasiliensis (S1 and PS2) and P. lutzii. TremC and H elements would have been present in a hypothetical ancestor common to P. brasiliensis and P. lutzii, while TremA, B and F elements were either acquired by P. brasiliensis or lost by P. lutzii after speciation. Although TremD and TremE share about 70% similarity, they are specific to P. brasiliensis and P. lutzii, respectively. This suggests that these elements could either have been present in a hypothetical common ancestor and have evolved divergently after the split between P. brasiliensis and P. Lutzii, or have been independently acquired by horizontal transfer.

Conclusions

New families of Tc1/mariner DNA transposons in the genomic assemblies of the Paracoccidioides species complex are described. Families were distinguished based on significant BLAST identities between transposases and/or TIRs. The expansion of Trem in a putative ancestor common to the species P. brasiliensis and P. lutzii would have given origin to TremC and TremH, while other elements could have been acquired or lost after speciation had occurred. The results may contribute to our understanding of the organization and architecture of genomes in the genus Paracoccidioides.  相似文献   

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