Circulating YKL-40 levels during human endotoxaemia

Abstract

YKL-40 is secreted by macrophages and neutrophils and patients with bacterial infections have elevated circulating YKL-40. The aim was to evaluate changes in plasma YKL-40 (determined by enzyme-linked immunosorbent assay (ELISA) at 0, 2, 4, 8, 24 and 32 h) in eight healthy volunteers after injection with Esherichia coli endotoxin or saline. Plasma YKL-40 increased after endotoxin injection from 31 μg/l (range 19-39 μg/l) to a maximum of 159 μg/ 1 (61-552 μg/l, P < 0.01) at 24 h. The finding that plasma YKL-40 increased after endotoxin injection compared with saline (P < 0.001) suggests that YKL-40 has a functional role in infections. © 2005 British Society for Immunology.