title: Identification of a subset of group B donors reactive with monoclonal anti-A reagent.
abstract: Two red blood cell (RBC) units labeled group B were returned to the source blood center after they had been retyped as AB by a transfusion service. The discrepancy could be reproduced, but only with the use of the transfusion service's reagent, Ortho Diagnostic's anti-A Bioclone (a licensed, blended, murine monoclonal anti-A reagent). RBCs from 35 of 3,458 random group B donors (1%) reacted with the monoclonal anti-A after immediate centrifugation. Reactivity was associated with high serum levels of B-gene-specified transferase and was caused by the MH04 component, a potent anti-A capable of detecting some examples of Ax RBCs. It is probable that the potency of MH04 permitted detection of low levels of A determinants synthesized by the donors' unusually strong B-gene-specified transferase. Transfer of N-acetylgalactosamine by B-gene-specified transferases, reported in vitro, has not been detected previously in vivo. Use of highly sensitive monoclonal reagents may result in clinically ambiguous blood grouping results.
authors.affiliation: Community Blood Center of Greater Kansas City, Missouri 64111.
authors.forename: M L
authors.initials: ML
authors.lastname: Beck
authors.forename: A D
authors.initials: AD
authors.lastname: Yates
authors.forename: J
authors.initials: J
authors.lastname: Hardman
authors.forename: M A
authors.initials: MA
authors.lastname: Kowalski
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics; D000911:Antibodies, Monoclonal; D001782:Blood Donors; D001788:Blood Grouping and Crossmatching; D004912:Erythrocytes / Q000276:immunology; D005189:False Positive Reactions; D005700:Galactosyltransferases / Q000097:blood; D006801:Humans; D017350:N-Acetylgalactosaminyltransferases; D010375:Pedigree; D011933:Reagent Kits, Diagnostic / Q000592:standards*; D012463:Saliva / Q000276:immunology
chemical_list: D000017:ABO Blood-Group System; D000911:Antibodies, Monoclonal; D011933:Reagent Kits, Diagnostic; D005700:Galactosyltransferases; D017350:N-Acetylgalactosaminyltransferases; C003742:UDPgalactosamine-galactose acetylgalactosaminyltransferase