Adhesion of the human pathogen Sporothrix schenckii to several extracellular matrix proteins

Abstract

The pathogenic fungus Sporothrix schenckii is the causative agent of sporotrichosis. This subcutaneous mycosis may disseminate in immunocompromised individuals and also affect several internal organs and tissues, most commonly the bone, joints and lung. Since adhesion is the first step involved with the dissemination of pathogens in the host, we have studied the interaction between S. schenckii and several extracellular matrix (ECM) proteins. The binding of two morphological phases of S. schenckii, yeast cells and conidia, to immobilized type II collagen, laminin, fibronectin, fibrinogen and thrombospondin was investigated. Poly (2-hydroxyethyl methacrylate) (poly-HEMA) was used as the negative control. Cell adhesion was assessed by ELISA with a rabbit anti-S. schenckii antiserum. The results indicate that both morphological phases of this fungus can bind significantly to type II collagen, fibronectin and laminin in comparison to the binding observed with BSA (used as blocking agent). The adhesion rate observed with the ECM proteins (type II collagen, fibronectin and laminin) was statistically significant (P<0.05) when compared to the adhesion obtained with BSA. No significant binding of conidia was observed to either fibrinogen or thrombospondin, but yeast cells did bind to the fibrinogen. Our results indicate that S. schenckii can bind to fibronectin, laminin and type II collagen and also show differences in binding capacity according to the morphological form of the fungus.

Purification, characterization and antioxidant properties of low molecular weight collagenous polypeptide (37 kDa) prepared from whale shark cartilage (Rhincodon typus)

“…2). A similar protein pattern for CII obtained from the articular cartilage of human and chicks has been reported in several studies (Lima et al 1999;Cao et al 2013). On the basis of the electrophoretic mobilities, the α-chain of the WS collagens hydrolyzed by thermolysin was degraded into smaller peptides with molecular weight ranging from 70 to 20 KDa.…”

Passive immunization with monoclonal antibody against a 70‐kDa putative adhesin of Sporothrix schenckii induces protection in murine sporotrichosis

“…5A). Previous work demonstrated that S. schenckii interacts with purified FN and LM, in immobilized and soluble forms [13,14]. Pretreatment of endothelial ECM with anti-LM and anti-FN significantly inhibited S. schenckii adhesion by 23.4 and 35.6%, respectively, as described by others [15,16].…”

Cell surface expression of adhesins for fibronectin correlates with virulence in Sporothrix schenckii

“…Previously, our group reported that S. schenckii adhered to fibronectin and laminin in soluble and immobilized forms (Lima et al, 1999(Lima et al, , 2001(Lima et al, , 2004 and that this is a key step for transposition of the endothelial barrier (Figueiredo et al, 2007). Here, the capacity of different isolates to bind fibronectin was investigated.…”

“…Previous studies demonstrated that S. schenckii yeast cells adhere to fibronectin in a dose-dependent manner and that this is a key step for crossing of the endothelial barrier (Lima et al, 1999(Lima et al, , 2001(Lima et al, , 2004Figueiredo et al, 2007). The binding of fibronectin to yeast cells of the four isolates was therefore evaluated by flow cytometry.…”

“…Our group previously reported that S. schenckii interacts with soluble and immobilized fibronectin; moreover, laminin and type II collagen were also reported as substrates for adherence of this pathogen (Lima et al, 1999(Lima et al, , 2001(Lima et al, , 2004. Study of independent isolates of Paracoccidioides brasiliensis revealed that the strains that were more virulent in animals exhibited enhanced adherence to extracellular matrix proteins in vitro (Hanna et al, 2000;Mendes-Giannini et al, 2006).…”