B. Rozalska et T. Wadstrom, INTERFERON-GAMMA, INTERLEUKIN-1 AND TUMOR-NECROSIS-FACTOR-ALPHA SYNTHESIS DURING EXPERIMENTAL MURINE STAPHYLOCOCCAL INFECTION, FEMS immunology and medical microbiology, 7(2), 1993, pp. 145-152
Several exotoxins of Staphylococcus aureus were shown to modulate the
host immune system by stimulation of monokine release. BALB/c mice inf
ected intravenously (i.v.) with live cells if S. aureus, strain Cowan
1, had a detectable serum level of TNF-alpha at 3, 4 and 5 h after inj
ection. When S. epidermidis (strain E3380, clinical isolate) was used
to infect mice, the level of TNF-alpha was lower (the detection limit
of the cytotoxicity assay with WEHI cells was 40 pg ml-1). Kinetics of
TNF synthesis was different from that observed in experimental infect
ions caused by Gram-negative bacteria. Similarly to TNF-alpha, IL-1alp
ha appears in a measurable level at 3 h after iv. injection of bacteri
a. The highest serum level of IFN-gamma was observed 12 h after infect
ion with both S. aureus and S. epidermidis. A quantity ten times more
of S. epidermidis than of S. aureus cells was required to induce simil
ar levels of TNF-alpha and IFN-gamma. Recombinant IFN-gamma administer
ed in vivo in four daily doses followed by infection of S. aureus resu
lted in increased elimination of bacteria from the spleen, liver and p
eritoneal cavity of mice.