Changes of Serum Cytokines ( TNF-alpha, IL-beta, IL-6 ) in Toxemic Mice Induced by Vibrio vulnificus Cytolysin

Park, Seok Don; Kim, Ju Seob; Cha, Seung Hoon

Abstract

BACKGROUND: Cytokines such as TNF-a, and IL-1, 6, 8 are thought to mediate many host responses in patients with sepsis through the release of many kinds of inflammatory mediators. Vibrio vulnificus is a virulent, halophilic, marine, and Gram-negative bacterium causing wound infections or primary sepsis with fulminant course. It has been known to produce many exocellular factors, such as cytolysin and exozymes, which are possible causes of shock and tissue damage.
OBJECTIVE
Our purpose was to investigate the changes of cytokines(TNF-a, Il-l p, and IL-6) after intravenous administration of V. vulnificus cytolysin which have known to be a major virulent factor for elucidating pathogenesis of septic shock.
METHODS
After administration of V. vulnificus cytolysin(20 hemolytic units) and physiologic saline through a mouse tail vein, we obtained blood samples from the heart according to a time course(0, 30, 60, 90, 120, 240, and 360 minutes). We measured serum concentrations of circulating TNF- a, IL-1 p, and IL-6 using commercially available immunoassay kits.
RESULTS
The serum concentration of TNF- a peaked at 60 min (1894 pg/ml, as compared with 829 pg/ml after saline administration), began to decrease at 90 min and fell to baseline at 360min. Concentration of IL-6 rose significantly at 90 min(>3,839 pg/ml) and began to decrease at 120 min, whereas the level of IL-1 0 increased slightly and the peaked around 90min(117 pg/ml) after the cytolysin injection.
CONCLUSION
We conclude that the host response to cytolysin is associated with a brief pulse of circulating cytokines in the early stage of sepsis caused by V. vulnipcus infection.