Cell surface expression of adhesins for fibronectin correlates with virulence in Sporothrix schenckii.
The virulence of four Sporothrix schenckii isolates was compared in a murine model of sporotrichosis, together with the protein pattern of the yeast cell surface and the capacity to bind the extracellular matrix protein fibronectin. Virulence was determined by the mortality rate, fungal burden and histopathology. Two clinical isolates were more virulent for C57BL/6 mice, but no direct correlation was seen between virulence and the clinical or environmental origin of the isolates. The lowest virulence was observed for an isolate recovered from a patient with meningeal sporotrichosis. Although all isolates could effectively disseminate, the dissemination patterns were not similar. Using flow cytometry analysis, we investigated the interaction of all the strains with fibronectin, and showed that the binding capacity correlated with virulence. Western blot analysis of S. schenckii cell wall extracts revealed positive bands for fibronectin in the range of 37-92 kDa. The 70 kDa adhesin was also recognized by a protective monoclonal antibody raised against a gp70 antigen of S. schenckii (mAb P6E7). Confocal microscopy confirmed the co-localization of fibronectin and mAb P6E7 on the yeast cell surface. To our knowledge, this is the first report identifying adhesins for fibronectin on the surface of this human pathogen.
Teixeira
Pedro Antônio Castelo
PAC
Departamento de Biologia Celular, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Brazil.
de Castro
Rafaela Alves
RA
Departamento de Biologia Celular, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Brazil.
Nascimento
Rosana Cícera
RC
Departamento de Análises Clínicas e Toxicológicas - Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Brazil.|Departamento de Biologia Celular, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Brazil.
Tronchin
Guy
G
Groupe d'Étude des Interactions Hôte-Pathogène, UPRES-EA 3142, Université d'Angers, Angers, France.
Pérez Torres
Armando
A
Laboratorio de Inmunología Comparada de Piel y Mucosas, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico.
Lazéra
Márcia
M
Instituto de Pesquisa Clínica Evandro Chagas Filho - Fiocruz, Rio de Janeiro, Brazil.
de Almeida
Sandro Rogério
SR
Departamento de Análises Clínicas e Toxicológicas - Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Brazil.
Bouchara
Jean-Philippe
JP
Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire, Angers, France.|Groupe d'Étude des Interactions Hôte-Pathogène, UPRES-EA 3142, Université d'Angers, Angers, France.
Loureiro Y Penha
Carla Veronica
CV
Departamento de Biologia Celular, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Brazil.
Lopes-Bezerra
Leila M
LM
Departamento de Biologia Celular, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Brazil.
D000818:Animals; D002448:Cell Adhesion; D005353:Fibronectins / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D013175:Sporothrix / Q000302:isolation & purification / Q000378:metabolism / Q000472:pathogenicity*; D013174:Sporotrichosis / Q000382:microbiology* / Q000473:pathology; D014774:Virulence
D005353:Fibronectins; D005656:Fungal Proteins; D008565:Membrane Proteins