Glucan administration induces multiple effects in animals which may involve cytokine secretion and induction of a Th1 immune response. We examined the secretion of selected cytokines by murine macrophage cell lines induced by exposure to scleroglucan and laminarin, using lipopolysaccharide (LPS) as a positive control. We examined TNF as an example of an inflammatory cytokine, IL12 as a cytokine that induces differentiation of CD4 lymphocytes to Th1 cells, and IL10 as an anti-inflammatory cytokine. We also examined binding of these glucans to the macrophage cell lines using inhibition of LPS binding using ligand binding kinetics flow cytometry. We found that scleroglucan induced TNF secretion from RAW264.7 cells and J774A.1 cells; and IL12 (p40) from J774A.1 cells, but did not cause IL10 secretion. Laminarin did not cause cytokine secretion. Both scleroglucan and laminarin blocked LPS binding to macrophages. We conclude that glucans cause cytokine secretion by murine macrophages and that they bind to these cells using LPS receptor(s).