Interleukin-8 Release in Baboon Septicemia Is Partially Dependent on Tumor Necrosis Factor

The role of tumor necrosis factor (TNF) in interleukin (IL)-8 release in septicemia in the baboon (2-h infusion of live Escherichia coli. 5×10 8 cfu/kg) was investigated. Four experiments were done: one control (n=7) and three with pretreatment to reduce TNF plasma levels. Pretreatment was with anti-TNF antibody (anti-TNF) 15 mg/kg, which neutralized circulating TNF (n=4); 0.5 mg/kg of anti-TNF, which reduced peak TNF from 6.2 ng/mL (controls) to 0.6 ng/mL (n=4); and a xanthine derivate (HWA 138), which reduced TNF to 1 ng/mL (n=5). With TNF levels <1 ng/mL, a significant reduction of circulating IL-8 from 10.4 ng/mL (peak) in controls to 1 ng/mL (peak) in anti-TNF-treated animals was found, but with HWA 138 only some decrease in IL-8 was seen