Coexpression of sialosyl-Tn (NeuAc alpha 2----6GalNAc alpha 1----O-Ser/Thr) and Tn (GalNAc alpha 1----O-Ser/Thr) blood group antigens on Tn erythrocytes.
Polyagglutinable erythrocytes expressing the rare human blood group phenotype Tn were tested for expression of both Tn (GalNAc alpha 1----O-Ser/Thr) and sialosyl-Tn (NeuAc alpha 2----6GalNAc alpha 1----O-Ser/Thr) antigens by agglutination with a panel of well-characterized monoclonal antibodies specifically directed to Tn and sialosyl-Tn antigens, respectively. Tn erythrocytes from 4 patients were strongly agglutinated by both sialosyl-Tn and Tn-specific monoclonal antibodies, indicating coexpression of sialosyl-Tn and Tn antigens on the cell membrane surface of Tn polyagglutinable erythrocytes. Human polyclonal anti-Tn antisera were found to express weak and variable anti-sialosyl-Tn antibodies in conjunction with the anti-Tn antibodies. The Tn phenotype thus involves not only the classically known Tn antigens but also sialosyl-Tn antigens. However, the human anti-Tn antibodies may be directed mainly toward the Tn antigen (GalNAc alpha 1----O-Ser/Thr).
Kjeldsen
T
T
Biomembrane Institute, University of Washington, Seattle.
Hakomori
S
S
Springer
G F
GF
Desai
P
P
Harris
T
T
Clausen
H
H
D000911:Antibodies, Monoclonal / Q000276:immunology; D000951:Antigens, Neoplasm / Q000235:genetics*; D015295:Antigens, Tumor-Associated, Carbohydrate; D001789:Blood Group Antigens / Q000235:genetics* / Q000276:immunology; D004903:Erythrocyte Aggregation; D004912:Erythrocytes / Q000276:immunology*; D006386:Hemagglutination Tests; D006801:Humans; D007106:Immune Sera / Q000276:immunology / Q000302:isolation & purification; D010641:Phenotype; D014158:Transcription, Genetic
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D015295:Antigens, Tumor-Associated, Carbohydrate; D001789:Blood Group Antigens; D007106:Immune Sera; C040286:Tn antigen; C055491:sialosyl-Tn antigen