Diagnostic significance of serum A and B glycosyltransferase assay for the classification of ABO subgroups

ABSTRACT

BACKGROUND: A and B transferase are glycosyltransferase that transfer N-acetylgalactosamine and D- galactose to H antigen, respectively and lead to the expression of A and B phenotypes in ABO blood group system. Reduced or no activities of serum A and B transferase were observed in some A and B subgroup individuals. Determining the activities of serum A and B transferase can be useful in discriminating rare A and B subgroups. MATERIALS AND METHODS: ABO typing, saliva test, adsorption elution test and serum transferase assay were performed on samples from 12 individuals showing ABO discrepancy or weakened cell typing reactions which were referred to the Seoul National University Hospital to confirm their ABO blood types. Serum transferase activity was assayed by determining the ability of serum to convert group 0 RBCs into A or B cells. RESULTS: Determination of serum ABO transferase activity was useful in the identification of Ael (3 cases), B. (2 cases), Bm (1 case), Am (1 case), Bx (1 case), 0 with weakened anti-A or anti-B (3 cases), and A without anti-B due to hypogammaglobulinemia (1 case). CONCLUSION: Determining serum A and B glycosyltransferase activity was proven to be a simple and useful tool for the classification of several ABO subgroups.(Korean J Blood Transfusion 10(1) 27-33, 1999)