The leukocyte surface antigens CD11b and CD18 mediate the oxidative burst activation of human peritoneal macrophages induced by type 1 fimbriated Escherichia coli.
Analysis by immunofluorescence-activated cell sorting of human peritoneal macrophages from patients undergoing intermittent peritoneal dialysis revealed that they express the CD11/CD18 surface antigens, with CD11b and CD18 as the predominant ones. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of immunoprecipitates obtained from lysates of 125I-labeled macrophages with rabbit polyclonal antibodies against the CD11a-c/CD18 complex or against CD18, revealed four radioactive bands corresponding to CD11a, CD11b, CD11c, and CD18. Monoclonal antibodies against CD11b and CD18 inhibited by 80 and 90%, respectively, the oxidative burst activation of the macrophages by type 1 fimbriated Escherichia coli, whereas monoclonal antibodies against CD11a, CD11c, and CD43 were without effect. Our results suggest that CD11b and CD18 (receptors for C3bi) serve also as receptors for mannose-specific E. coli on human peritoneal macrophages and may be involved in the lectinophagocytosis of the bacteria by these cells.
Gbarah
A
A
Department of Membrane Research and Biophysics, Weizmann Institute of Science, Rehovot, Israel.
Gahmberg
C G
CG
Boner
G
G
Sharon
N
N
D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000502:physiology*; D001422:Bacterial Adhesion / Q000276:immunology; D018821:CD18 Antigens; D004926:Escherichia coli / Q000276:immunology*; D010861:Fimbriae, Bacterial / Q000276:immunology; D006801:Humans; D066298:In Vitro Techniques; D008262:Macrophage Activation / Q000276:immunology*; D016177:Macrophage-1 Antigen / Q000502:physiology*; D010529:Peritoneal Cavity / Q000166:cytology; D016897:Respiratory Burst / Q000276:immunology*
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018821:CD18 Antigens; D016177:Macrophage-1 Antigen