Recognition of xenogeneic erythrocytes: the GalNAc/Gal-particle receptor of rat liver macrophages mediates or participates in recognition.
We studied mechanisms that mediate recognition of human erythrocytes (HRBC) and sheep erythrocytes (SRBC) by rat liver macrophages. We used an in vitro cell binding assay that allows spontaneous formation of cell contacts. Binding of HRBC to rat macrophages shows the following characteristics: inhibition studies with several monosaccharides and oligosaccharides yield complete inhibition of cell contacts with saccharides, which block the GalNAc/Gal-particle receptor on rat liver macrophages. We found the inhibition pattern: N-acetyl-D-galactosamine, lactose greater than D-galactose, D-fucose greater than L-fucose much greater than N-acetyl-D-glucosamine. Cell binding is dependent on the presence of calcium ions, but not influenced by heat-aggregated IgG or gangliosides. The inhibition pattern was the same after treatment of HRBC with neuraminidase. Therefore, binding of HRBC, as well as binding of neuraminidase-treated HRBC, is mediated by the GalNAc/Gal-particle receptor. Binding of SRBC is partly inhibited by galactose-related saccharides. Binding is also partly inhibited by heat-aggregated IgG, gangliosides, and L-fucose. Complete inhibition of cell contacts with SRBC is achieved by combination of all inhibitors. We therefore conclude that binding of SRBC is mediated by several different mechanisms, including the GalNAc/Gal-particle receptor. Binding of neuraminidase-treated SRBC, however, was found to be completely inhibited by saccharides, which block the GalNAc/Gal-particle receptor. We conclude that the GalNAc/Gal-particle receptor mediates or participates in recognition of non-self structures.
Mohr
M
M
Department of Medicine, University of Düsseldorf, F.R.G.
Kolb
H
H
Kolb-Bachofen
V
V
Schlepper-Schäfer
J
J
D000818:Animals; D002449:Cell Aggregation; D004912:Erythrocytes / Q000502:physiology*; D006023:Glycoproteins / Q000378:metabolism; D006801:Humans; D007728:Kupffer Cells / Q000502:physiology; D008099:Liver / Q000166:cytology; D008264:Macrophages / Q000502:physiology*; D009005:Monosaccharides / Q000378:metabolism; D009844:Oligosaccharides / Q000378:metabolism; D051381:Rats; D011956:Receptors, Cell Surface / Q000502:physiology*; D012756:Sheep
D006023:Glycoproteins; D009005:Monosaccharides; D009844:Oligosaccharides; D011956:Receptors, Cell Surface; C039707:galactose receptor