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

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 outbr...

Full description

Bibliographic Details
Published in:PLOS Neglected Tropical Diseases
Main Authors: Anderson Messias Rodrigues, Geisa Ferreira Fernandes, Leticia Mendes Araujo, Paula Portella Della Terra, Priscila Oliveira dos Santos, Sandro Antonio Pereira, Tânia Maria Pacheco Schubach, Eva Burger, Leila Maria Lopes-Bezerra, Zoilo Pires de Camargo
Format: Article in Journal/Newspaper
Language:English
Published: Public Library of Science (PLoS) 2015
Subjects:
Online Access:https://doi.org/10.1371/journal.pntd.0004016
https://doaj.org/article/d8e38346b49b4ebba582149b8691ea02
Description
Summary: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 ...