Role of CD11b/CD18 in priming of human leukocytes by endotoxin glycoforms from Escherichia coli

The primary objective of this study was to determine the role of β2 integrin α-subunit (CD11b) in the mechanism of human polymorphonuclear leukocyte (PML) priming by S or Re endotoxin glycoforms from Escherichia coli for fMLP-induced respiratory burst. Similar priming activity of S and Re endotoxin glycoforms for fMLP-induced reactive oxygen species (ROS) generation from primed PML was found. Anti-CD11b antibodies (clone ICRF 44) as well as isotypematched immunoglobulin G1 (clone MOPC-21) do not influence the fMLP-induced ROS generation from unprimed PML. Antibodies against CD11b do not change fMLP-induced ROS generation from endotoxin-primed PML as well. The involvement of different isoforms of Fcγ receptors in fMLP-induced ROS generation from activated PML is proposed.