Binding of activated macrophages to tumor cells through a macrophage lectin and its role in macrophage tumoricidal activity.
A 45-60 kDa Gal/GalNAc-specific macrophage lectin was found to participate in the interaction between tumor cells and tumoricidal macrophages activated by an antitumor streptococcal preparation, OK-432, and in the tumoricidal activity of the activated macrophages. The binding between OK-432-elicited activated macrophages and murine mastocytoma P-815 cells was inhibited on preincubation of the macrophages with a neoglycoprotein (Gal-BSA) or a complex-type glycopeptide (unit B) which was a specific inhibitor of the macrophage lectin. This binding of the macrophages to P-815 cells was also inhibited on the addition of anti-macrophage lectin antiserum. Contrary to the case of OK-432-elicited macrophages, the binding of thioglycolate-elicited (responsive) macrophages to P-815 cells was inhibited only a little by Gal-BSA and unit B, and not inhibited by the antiserum. Furthermore, the tumoricidal activity of the activated macrophages was inhibited by the addition of the anti-macrophage lectin antiserum. These results suggest that the binding of activated macrophages to tumor cells through the Gal/GalNAc-specific macrophage lectin is an important part of the tumor cell killing mechanism.
Division of Chemical Toxicology and Immunochemistry, Faculty of Pharmaceutical Sciences, University of Tokyo.
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Oda
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Sato
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Toyoshima
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Osawa
D000818:Animals; D002241:Carbohydrates / Q000494:pharmacology; D037102:Lectins / Q000037:antagonists & inhibitors / Q000276:immunology / Q000378:metabolism*; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology / Q000378:metabolism* / Q000502:physiology; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009844:Oligosaccharides / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000378:metabolism*
D002241:Carbohydrates; D037102:Lectins; D009844:Oligosaccharides