Abstract
The characteristics of the recognition system involved in the receptor mediated endocytosis of the neoglycoprotein, fucose-human serum albumin (HSA) were studied. It was found that (i) fucose-HSA showed strong affinity binding and uptake by various macrophages; (ii) binding was specific for L-fucose and D-mannose; (iii) binding was found to be inhibited by oxidant like H2O2 and swainsonine whereas it was elevated by dexamethasone; (iv) clearance of 125I-fucose-HSA was rapid and strongly inhibited by unlabelled fucose-HSA. Greater than 70% of fucose-HSA was found in liver and more than 60% of this was found in liver lysosomes; (v) uptake of fucose-HSA was thirty-fold more efficient in liver macrophages (Kupffer cells) than in hepatocytes; (vi) moreover, mannose-HSA and ovalbumin which are potent inhibitors of mannose/N-acetylglucosamine receptors inhibited clearance and uptake of fucose-HSA by liver as well as by isolated Kupffer cells suggesting the involvement of both fucose and mannose receptors or a single type of receptor having greater affinity for fucose-HSA than for mannose-HSA. These results emphasize the important role of fucose-terminated glycoproteins in site-specific drug targeting.
Original language | English (US) |
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Pages (from-to) | 109-116 |
Number of pages | 8 |
Journal | Molecular and Cellular Biochemistry |
Volume | 156 |
Issue number | 2 |
DOIs | |
State | Published - Apr 22 1996 |
Keywords
- Endocytosis
- Macrophages
- Neoglycoproteins
- Sugar receptors
ASJC Scopus subject areas
- Molecular Biology
- Clinical Biochemistry
- Cell Biology