In female Balb/c mice lethal infection was induced by intraperitoneal injection of Gram-positive bacteria, Staphylococcus epidermidis (S. epidermidis), or Gram-negative bacteria, Escherichia coli (E. coli). Serum TNF-alpha levels were examined 1, 2, 3, 4, 6, 9, and 24 h thereafter. The results demonstrated that S. epidermidis or E. coli - induced sepsis is accompanied by TNF-alpha production, most pronounced at 2 h after infection, with a biphasic disappearance of the cytokine from circulation within 24 h after infection. The lethal dose of S. epidermidis was tenfold higher than the corresponding dose of E. coli and death of mice in the S. epidermidis-induced sepsis took place after a twofold longer time than in E. coli induced sepsis. The data suggests that TNF-alpha represents a septic shock mediator also in S. epidermidis infection. The circulating TNF-alpha , however, does not seem to represent the factor directly responsible for lethality of the infections.

Keywords: TNF-alpha, staphylococci, Endotoxins, Sepsis