Histopathologic study on the Toxicity of Cytolysin Produced by Vibrio vulnificus / 대한해부학회지

ABSTRACT

Vibrio vulnificus is an estuarine bacterium which causes septicemia and serious wound infection. But the pathogenesis of Vibrio vulnificus infection is unknown. Among the exotoxins secreted by Vibrio vulnificus, cytolysin has been incriminated as one of the potent virulence determinants. In order to clarify the toxicity of cytolysin in mice, the morphological changes of various organs after the intravenous injection of cytolysin were observed. The pathological changes of mouse due to a single intravenous injection of Vibrio vulnificus cytolysin (8 hemolytic units) were as follows Blood volume was decreased, and pleural effusion, vascular permeability of lungs, wet weight and volume of lungs were increased. And cytolysin was lead to patchy hemorrhage of pulmonary surface. The microscopic findings of mouse lung in experimental group were characterized by (1) extensive perivascular edema; (2) accumulation of intraalveolar fluid with electron dense particles; (3) narrowing of alveolar space; (4) leukocyte infiltration in perivascular and intraalveolar space; (5) vasodilatation of capillary; (6) damaged capillary endothelial cells and alveolar epithelial cells; (7) interstitial edema of interalveolar septa; (8) disorganization of collagen bundles. These results indicate that the lung may be an important target organ of cytolysin in the pathologenesis and lethal activity of Vibrio vulnificus infections.