Membrane lectins on human monocytes. Maturation-dependent modulation of 6-phosphomannose and mannose receptors.
Freshly isolated human monocytes, which do not contain cell-surface mannose-specific receptors, bind mannose 6-phosphate and actively endocytose mannose 6-phosphate-bearing neoglycoproteins (6-P-Man-F-BSA). Three days after isolation, human monocytes endocytose very actively 6-P-Man-F-BSA as well as Man-F-BSA, and the endocytosed neoglycoproteins are rapidly degraded. These results were obtained in quantitative flow cytofluorometry by using a panel of fluoresceinylated sugar-substituted serum albumins (neoglycoproteins). Thus, in contrast to mannose receptors which appear only after maturation, mannose 6-phosphate receptors are already present on freshly isolated human monocytes.
Roche
A C
AC
Midoux
P
P
Bouchard
P
P
Monsigny
M
M
D002352:Carrier Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000032:analysis; D004705:Endocytosis; D006801:Humans; D037102:Lectins / Q000032:analysis*; D008360:Mannosephosphates / Q000378:metabolism; D009000:Monocytes / Q000032:analysis*; D017527:Receptor, IGF Type 2
D002352:Carrier Proteins; D037102:Lectins; D008360:Mannosephosphates; D017527:Receptor, IGF Type 2; C027693:mannose-6-phosphate