ISSN:
1573-4986
Keywords:
serum lectin
;
complement activation
;
cytotoxicity
;
1-deoxymannojirimycin
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Serum mannan-binding protein (S-MBP), a lectin specific for mannose andN-acetylglucosamine, activates complement through the classical pathway. With the help of complement, S-MBP lyses red blood cells which have been coated with yeast mannan and kills bacteria which haveN-acetylglucosamine and/orl-glycero-d-manno-heptose on their core oligosaccharide. In this study, we examined whether mammalian cells, on which S-MBP could bound, are killed by a complement-dependent mechanism. When baby hamster kidney (BHK) cells were treated with an α-mannosidase inhibitor, 1-deoxymannojirimycin (dMM), most of the cellular oligosaccharides were transformed from the complex-type to the high mannose-type. S-MBP bound to the dMM-treated BHK cells in the presence of Ca2+, and this binding was eliminated by mannose. When dMM-treated cells, labelled with51Cr, were incubated with complement, radioactivity was released in a dose-dependent manner by S-MBP and complement. This release was not observed with heat-inactivated complement. These observations suggest that S-MBP is able, with the help of complement, to kill not only exogenous microorganisms but also mammalian cells which have high mannose-type oligosaccharides exposed on their surfaces.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00731203
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