Limits...
Proteomics-Based Characterization of the Humoral Immune Response in Sporotrichosis: Toward Discovery of Potential Diagnostic and Vaccine Antigens.

Rodrigues AM, Fernandes GF, Araujo LM, Della Terra PP, dos Santos PO, Pereira SA, Schubach TM, Burger E, Lopes-Bezerra LM, de Camargo ZP - PLoS Negl Trop Dis (2015)

Bottom Line: Epidemiological surveillance has highlighted an overwhelming occurrence of the highly pathogenic fungus Sporothrix brasiliensis during feline outbreaks, leading to massive transmissions to humans.Antigen profiling included protein extracts from the closest known relatives S. brasiliensis and S. schenckii.We propose that 3-carboxymuconate cyclase has potential for the serological diagnosis of sporotrichosis and as target for the development of an effective multi-species vaccine against sporotrichosis in animals and humans.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Immunology and Parasitology, Discipline of Cellular Biology, Federal University of São Paulo, São Paulo, Brazil.

ABSTRACT

Background: Sporothrix schenckii and associated species are agents of human and animal sporotrichosis that cause large sapronoses and zoonoses worldwide. Epidemiological surveillance has highlighted an overwhelming occurrence of the highly pathogenic fungus Sporothrix brasiliensis during feline outbreaks, leading to massive transmissions to humans. Early diagnosis of feline sporotrichosis by demonstrating the presence of a surrogate marker of infection can have a key role for selecting appropriate disease control measures and minimizing zoonotic transmission to humans.

Methodology: We explored the presence and diversity of serum antibodies (IgG) specific against Sporothrix antigens in cats with sporotrichosis and evaluated the utility of these antibodies for serodiagnosis. Antigen profiling included protein extracts from the closest known relatives S. brasiliensis and S. schenckii. Enzyme-linked immunosorbent assays and immunoblotting enabled us to characterize the major antigens of feline sporotrichosis from sera from cats with sporotrichosis (n = 49), healthy cats (n = 19), and cats with other diseases (n = 20).

Principal findings: Enzyme-linked immunosorbent assay-based quantitation of anti-Sporothrix IgG exhibited high sensitivity and specificity in cats with sporotrichosis (area under the curve, 1.0; 95% confidence interval, 0.94-1; P<0.0001) versus controls. The two sets of Sporothrix antigens were remarkably cross-reactive, supporting the hypothesis that antigenic epitopes may be conserved among closely related agents. One-dimensional immunoblotting indicated that 3-carboxymuconate cyclase (a 60-kDa protein in S. brasiliensis and a 70-kDa protein in S. schenckii) is the immunodominant antigen in feline sporotrichosis. Two-dimensional immunoblotting revealed six IgG-reactive isoforms of gp60 in the S. brasiliensis proteome, similar to the humoral response found in human sporotrichosis.

Conclusions: A convergent IgG-response in various hosts (mice, cats, and humans) has important implications for our understanding of the coevolution of Sporothrix and its warm-blooded hosts. We propose that 3-carboxymuconate cyclase has potential for the serological diagnosis of sporotrichosis and as target for the development of an effective multi-species vaccine against sporotrichosis in animals and humans.

No MeSH data available.


Related in: MedlinePlus

ELISA of antibody titers in sera from cats (n = 49) with confirmed sporotrichosis (Spor +).The range of antibody titers against S. brasiliensis (A) and S. schenckii s. str. (B) antigens were expressed as optical density (absorbance). Each symbol represents an individual cat; horizontal lines indicate the mean. Data are representative of two independent experiments. Titers from the control group (NFS: non-feline sporotrichosis) were significantly lower (P<0.001) than titers from infected cats (Spor +). Further information about ELISA statistics appears in S1 Table.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4549111&req=5

pntd.0004016.g001: ELISA of antibody titers in sera from cats (n = 49) with confirmed sporotrichosis (Spor +).The range of antibody titers against S. brasiliensis (A) and S. schenckii s. str. (B) antigens were expressed as optical density (absorbance). Each symbol represents an individual cat; horizontal lines indicate the mean. Data are representative of two independent experiments. Titers from the control group (NFS: non-feline sporotrichosis) were significantly lower (P<0.001) than titers from infected cats (Spor +). Further information about ELISA statistics appears in S1 Table.

Mentions: We previously reported a high prevalence of S. brasiliensis in feline sporotrichosis outbreaks [8, 9, 20]. Based on this information, the main goal of the present investigation was to evaluate the presence and diversity of serum-derived antibodies against S. brasiliensis antigens in naturally infected cats. Further, we previously proposed the existence of a convergent humoral response in human sporotrichosis against antigens from S. brasiliensis, S. schenckii, and S. globosa [45]. To establish whether S. brasiliensis and S. schenckii express different antigens, we assessed whole cellular protein extracts from two strains of S. brasiliensis plus two strains of S. schenckii s. str. that were previously characterized by molecular [8, 9, 25, 54] and serological [3, 44–47] methods. Remarkably, and in support of our hypothesis that immunological distance increases with phylogenetic distance, sera from these cats reacted similarly, with no significant differences in titer between ELISA plates coated with proteins from S. brasiliensis or S. schenckii (Fig 1).


Proteomics-Based Characterization of the Humoral Immune Response in Sporotrichosis: Toward Discovery of Potential Diagnostic and Vaccine Antigens.

Rodrigues AM, Fernandes GF, Araujo LM, Della Terra PP, dos Santos PO, Pereira SA, Schubach TM, Burger E, Lopes-Bezerra LM, de Camargo ZP - PLoS Negl Trop Dis (2015)

ELISA of antibody titers in sera from cats (n = 49) with confirmed sporotrichosis (Spor +).The range of antibody titers against S. brasiliensis (A) and S. schenckii s. str. (B) antigens were expressed as optical density (absorbance). Each symbol represents an individual cat; horizontal lines indicate the mean. Data are representative of two independent experiments. Titers from the control group (NFS: non-feline sporotrichosis) were significantly lower (P<0.001) than titers from infected cats (Spor +). Further information about ELISA statistics appears in S1 Table.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4549111&req=5

pntd.0004016.g001: ELISA of antibody titers in sera from cats (n = 49) with confirmed sporotrichosis (Spor +).The range of antibody titers against S. brasiliensis (A) and S. schenckii s. str. (B) antigens were expressed as optical density (absorbance). Each symbol represents an individual cat; horizontal lines indicate the mean. Data are representative of two independent experiments. Titers from the control group (NFS: non-feline sporotrichosis) were significantly lower (P<0.001) than titers from infected cats (Spor +). Further information about ELISA statistics appears in S1 Table.
Mentions: We previously reported a high prevalence of S. brasiliensis in feline sporotrichosis outbreaks [8, 9, 20]. Based on this information, the main goal of the present investigation was to evaluate the presence and diversity of serum-derived antibodies against S. brasiliensis antigens in naturally infected cats. Further, we previously proposed the existence of a convergent humoral response in human sporotrichosis against antigens from S. brasiliensis, S. schenckii, and S. globosa [45]. To establish whether S. brasiliensis and S. schenckii express different antigens, we assessed whole cellular protein extracts from two strains of S. brasiliensis plus two strains of S. schenckii s. str. that were previously characterized by molecular [8, 9, 25, 54] and serological [3, 44–47] methods. Remarkably, and in support of our hypothesis that immunological distance increases with phylogenetic distance, sera from these cats reacted similarly, with no significant differences in titer between ELISA plates coated with proteins from S. brasiliensis or S. schenckii (Fig 1).

Bottom Line: Epidemiological surveillance has highlighted an overwhelming occurrence of the highly pathogenic fungus Sporothrix brasiliensis during feline outbreaks, leading to massive transmissions to humans.Antigen profiling included protein extracts from the closest known relatives S. brasiliensis and S. schenckii.We propose that 3-carboxymuconate cyclase has potential for the serological diagnosis of sporotrichosis and as target for the development of an effective multi-species vaccine against sporotrichosis in animals and humans.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Immunology and Parasitology, Discipline of Cellular Biology, Federal University of São Paulo, São Paulo, Brazil.

ABSTRACT

Background: Sporothrix schenckii and associated species are agents of human and animal sporotrichosis that cause large sapronoses and zoonoses worldwide. Epidemiological surveillance has highlighted an overwhelming occurrence of the highly pathogenic fungus Sporothrix brasiliensis during feline outbreaks, leading to massive transmissions to humans. Early diagnosis of feline sporotrichosis by demonstrating the presence of a surrogate marker of infection can have a key role for selecting appropriate disease control measures and minimizing zoonotic transmission to humans.

Methodology: We explored the presence and diversity of serum antibodies (IgG) specific against Sporothrix antigens in cats with sporotrichosis and evaluated the utility of these antibodies for serodiagnosis. Antigen profiling included protein extracts from the closest known relatives S. brasiliensis and S. schenckii. Enzyme-linked immunosorbent assays and immunoblotting enabled us to characterize the major antigens of feline sporotrichosis from sera from cats with sporotrichosis (n = 49), healthy cats (n = 19), and cats with other diseases (n = 20).

Principal findings: Enzyme-linked immunosorbent assay-based quantitation of anti-Sporothrix IgG exhibited high sensitivity and specificity in cats with sporotrichosis (area under the curve, 1.0; 95% confidence interval, 0.94-1; P<0.0001) versus controls. The two sets of Sporothrix antigens were remarkably cross-reactive, supporting the hypothesis that antigenic epitopes may be conserved among closely related agents. One-dimensional immunoblotting indicated that 3-carboxymuconate cyclase (a 60-kDa protein in S. brasiliensis and a 70-kDa protein in S. schenckii) is the immunodominant antigen in feline sporotrichosis. Two-dimensional immunoblotting revealed six IgG-reactive isoforms of gp60 in the S. brasiliensis proteome, similar to the humoral response found in human sporotrichosis.

Conclusions: A convergent IgG-response in various hosts (mice, cats, and humans) has important implications for our understanding of the coevolution of Sporothrix and its warm-blooded hosts. We propose that 3-carboxymuconate cyclase has potential for the serological diagnosis of sporotrichosis and as target for the development of an effective multi-species vaccine against sporotrichosis in animals and humans.

No MeSH data available.


Related in: MedlinePlus