Late expression of M and N antigens on glycophorin A during erythroid differentiation.
The M/N blood groups are carried by the major human red cell sialoglycoprotein, glycophorin A. O-glyosidic carbohydrate is needed for the activity, but the M/N specificity is due to amino acid replacements in the NH2-terminal portion of the molecule. We have used monoclonal antibodies specific for M and N blood groups to study their expression during normal erythropoiesis. Here we report that the M/N blood group activities are very weakly or not at all expressed before the polychromatic normoblast stage. Using polyclonal anti-glycophorin A antiserum, it was shown that glycophorin A molecules are already abundantly present on the earliest morphologically recognizable erythroid precursor, the proerythroblast. These findings can be explained by our previous observation that the O-glycosylation of glycophorin A gradually increases during erythroid maturation.
M
M
Ekblom
C G
CG
Gahmberg
L C
LC
Andersson
D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D000939:Epitopes; D004910:Erythrocyte Membrane / Q000276:immunology*; D004912:Erythrocytes / Q000166:cytology; D004920:Erythropoiesis; D006021:Glycophorins / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D008951:MNSs Blood-Group System / Q000276:immunology*; D012795:Sialoglycoproteins / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000939:Epitopes; D006021:Glycophorins; D008951:MNSs Blood-Group System; D012795:Sialoglycoproteins