N-glycosidase treatment of Colo 205 cells interferes with hIFN-gamma induced HLA-DR expression.
We investigated the effects of N-glycosidase treatment on the interferon-gamma (IFN-gamma) induced HLA-DR expression of Colo 205 cells. N-glycosidase treatment resulted in a significant decrease of IFN-gamma induced HLA-DR specific immunofluorescence intensity ranging from complete reduction to approximately 30% of that of untreated control cells depending on the IFN-gamma dose. IFN-gamma binding studies showed that this was due to a severe reduction in IFN-gamma binding capacity of N-glycosidase treated cells. Since the number of cell membrane IFN-gamma receptors (IFN-gamma-Rs) was virtually unchanged as revealed by immunofluorescence analysis with a hIFN-gamma-R specific monoclonal antibody this indicates that N-linked carbohydrates play an important role in signal transduction and ligand binding capacity of the hIFN-gamma-R and strengthens the view that carbohydrate moieties of receptor proteins are of greater functional significance than originally anticipated.
Fischer
T
T
Max-Planck-Society, Medical Clinic, University of Göttingen, FRG.
Wiegmann
K
K
Pfizenmaier
K
K
D002460:Cell Line; D006026:Glycoside Hydrolases / Q000494:pharmacology*; D006031:Glycosylation; D006684:HLA-DR Antigens; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism / Q000494:pharmacology*; D011971:Receptors, Immunologic / Q000187:drug effects / Q000378:metabolism; D017471:Receptors, Interferon
D006684:HLA-DR Antigens; D011971:Receptors, Immunologic; D017471:Receptors, Interferon; D007371:Interferon-gamma; D006026:Glycoside Hydrolases