Interaction of host and Staphylococcus aureus protease-system regulates virulence and pathogenicity

Abstract

Staphylococcus aureus causes various health care-and community-associated infections as well as certain chronic TH2 driven inflammatory diseases. It is a potent pathogen with serious virulence and associated high morbidity. Severe pathogenicity is accredited to the S. aureus secreted virulence factors such as proteases and host protease modulators. These virulence factors promote adhesion and invasion of bacteria through damage of tight junction barrier and keratinocytes. They inhibit activation and transmigration of various immune cells such as neutrophils (and neutrophil proteases) to evade opsono-phagocytosis and intracellular bacterial killing. Additionally, they protect the bacteria from extracellular killing by disrupting integrity of extracellular matrix. Platelet activation and agglutination is also impaired by these factors. They also block the classical as well as alternative pathways of complement activation and assist in spread of infection through blood and tissue. As these factors are exquisite factors of S. aureus mediated disease development, we have focused on review of diversification of various protease-system associated virulence factors, their structural building, diverse role in disease development and available therapeutic counter measures. This review summarises the role of protease-associated virulence factors during invasion and progression of disease.

WITHDRAWN:Staphylococcus aureus-serineprotease-like protein B (SplB) activates PAR2 and induces endothelial barrier dysfunction

“…Extracellular proteases of S. aureus are known to play an important role in the pathogenesis (37)(38)(39)(40)(41)(42). For example, the V8 protease and staphopains of S. aureus have been shown to alter the integrity of the airway epithelial barrier, thereby promoting lung damage (43).…”

“…The species S. aureus harbors a broad spectrum of extracellular virulence factors, among them several proteases, namely aureolysin, V8 protease (SspA), the staphopains A and B (ScpA and SspB), the exfoliative toxins A and B, and the serine protease-like proteins (Spls) A-F (35, 36). Extracellular proteases of S. aureus are known to play an important role in the pathogenesis (37–42). For example, the V8 protease and staphopains of S. aureus have been shown to alter the integrity of the airway epithelial barrier, thereby promoting lung damage (43).…”

Identification of MMP-like protein from Streptococcus mitis

“…However, very few virulence factors have been identified and characterized. Bacterial proteases are major virulence factors in various infectious diseases [14,15]. They promote the adhesion of bacteria to host tissues and invasion into the tight junction barrier of epithelial cells.…”

Host-Pathogen Adhesion as the Basis of Innovative Diagnostics for Emerging Pathogens

“…The severity of an infectious disease depends on the level of invasiveness and the extent of host cell and tissue damage caused by the pathogen involved [ 8 ]. A varying degree of virulence can be observed across different pathogens and among different strains of a single pathogen [ 9 ]. Virulence is a complicated concept in microbial pathogenesis since it depends not only on the infectious agent but also on host cell susceptibility [ 10 ].…”