Neopterin and Tumor Necrosis Factor-α : Two Markers of Monocyte/ Macrophage Activation in a Septic Baboon Model

Abstract

A hyperdynamic sepsis model in adult baboons was set up to follow the time course of TNF-Cl, endotoxin and neopterin. Continuous intravenous administration of 5.108 CFU/kg live E. coli over 2 hours was followed by a seventy hours observation period. In this experimental set up TNF -Cl shows a pronounced peak after 2 hours and a return to baseline after 4 hours. By 20 - 24 hours neopterin peaks in this subchronic set up and shows only a reduction to half maximum values during the observation period. Another finding is the fast clearance of bacteria and consecutively LPS from the circulation. We conceive that monocyte/macrophage activation seems to occur on at least two levels. The diagnostic usefulness of neopterin in routine measurement is in part explained by these findings.