TLR2-mediated ROS production by mouse peritoneal macrophages was studied by luminoldependent chemiluminescence under conditions of cell stimulation with zymosan (TLR2/6 ligand) and peptidoglycan (TLR2/1 ligand). ROS production by macrophages stimulated with zymosan and peptidoglycan simultaneously depended on the ratio of ligand concentrations. Three effects were revealed: additivity of the stimulating effects of the ligands used, competitive ligand binding, and effect of macrophage priming with peptidoglycan during cell stimulation with zymosan. The mechanisms of these effects are discussed.
Keywords: TLR2 ligands; Toll-like receptor 2; chemiluminescence; macrophages; reactive oxygen species.