Characterization of hemorrhagic dermatosis induced by metalloprotease of pathogenic vibrios.

创伤弧菌是一种机会致病菌，可引起伤口感染和败血症，其特征是皮肤出血和水肿性损伤。这种人类病原体分泌一种金属蛋白酶(创伤弧菌蛋白酶(VVP))作为重要的毒力决定因素。皮肤背部皮内注射包括VVP在内的多种细菌金属蛋白酶时，VVP的出血活性最强。细菌金属蛋白水解酶的体内活性与重组基底膜凝胶的体外出血活性显著相关。在两种主要的基底膜成分(层粘连蛋白和IV型胶原)中，只有IV型胶原容易被VVP消化。皮下注射VVP的组织病理学观察显示，真皮深部和皮下组织损伤严重。真皮和皮下组织血管附近可见脂肪细胞(脂肪细胞或脂肪细胞)出血和肿胀。出血区毛细血管破坏或充血。对VVP引起的出血行为的组织病理学观察表明，血管内皮细胞的坏死是毛细血管降解的另一种可能性。

Vibrio vulnificus is an opportunistic pathogen causing wound infections and septicemia, characterized by hemorrhagic and edematous damage to the skin. This human pathogen secretes a metalloprotease (V. vulnificus protease {VVP}) as an important virulence determinant. When several bacterial metalloproteases including VVP were injected intradermally into dorsal skin, VVP showed the greatest hemorrhagic activity. The level of the in vivo proteolytic activity of the bacterial metalloprotease was significantly correlated with that of the in vitro hemorrhagic activity for the reconstituted basement membrane gel. Of two major basement membrane components (laminin and type IV collagen), only type IV collagen was easily digested by VVP. Histopathological observations of skin injected with VVP indicated the severe damages in deep region of dermis and subcutaneous tissue. In these portion, hemorrhage and swelling of lipocyte (fat cell or adipose cell) were observed near the blood vessels in the dermis and subcutaneous tissues. The capillary vessels in hemorrhagic region were destroyed or congested with blood. Histopathological observations of the hemorrhagic actions induced by VVP indicated the another possibilities of the degradation of capillary vessels by the necrosis of endothelial cells.