Rabbit Plasma Fibronectin Levels Associated withStaphylococcusaureusEnterotoxin B: An Acute-Phase Reaction

Abstract

Variation in fibronectin (Fn) levels and white blood cell counts (WBC) following staphylococcal enterotoxin B (SEB) or SEB + cryoprecipitate containing Fn challenge was studied in New Zealand white rabbits. Increased plasma Fn levels were observed 2 h after the intravenous injection of SEB and peaked at 48–72 h (from a mean level 194.6 ± 4.5 µg/ml prechallenge Fn level to a 72-hour postchallenge mean level of 407.9 ± 25.4 µg/ml). Fn levels then decreased over the succeeding 5 days to approximately prechallenge levels. The total WBC count decreased by 88% within 2 h after the SEB injection. A slow increase in circulatory WBC was observed over the next 24 h. SEB caused an increase in plasma Fn levels and decreased WBC counts with lymphopenia that was followed by a normal lymphocyte count within 5 days. These data suggest that an acute-phase reaction was induced by interleukin-1. Fn prophylaxis provided no change in clinical signs when given at the time of SEB injection.

Adrenocorticotrophic hormone fails to alter plasma fibrinogen and fibronectin values in calves but does so in rabbits

“…For example, C-reactive protein is recognized as a classic acute-phase protein in man (Pepys and Baltz, 1983) but, while it is also an acute-phase reactant in dogs (Caspi et al, 1987;Eckersall et al, 1991), it does not appear to be so in the cow (Maudsley et aL, 1987). Similarly, fibronectin has been shown to respond as an acute-phase reactant in rats (Pick-Kober et aL, 1986, Stecher et aL, 1986, in rabbits (Lichen, 1988;Bawdon et al, 1989;Gentry et al, 1991) and in chickens (Amrani et al, 1986), while in man the fibronectin response to stress and inflammation is more variable (Zerlauth and Wolf, 1984;Fleck and Myers, 1985). In a recent study in pregnant mares, similar marked and persistent elevations in plasma fibrinogen and fibronectin were observed at and immediately following the stress of parturition .…”