Blood group A immunodeterminants on human red cells differ in biologic activity and sensitivity to alpha-N-acetylgalactosaminidase
Autor: | G.B. Naff, G. Larson, L.C. Hoskins |
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Rok vydání: | 2003 |
Předmět: |
Erythrocytes
Glycoconjugate Immunology Oligosaccharides Glycosphingolipids Epitope ABO Blood-Group System alpha-N-Acetylgalactosaminidase Blood cell Epitopes Lectins medicine Humans Immunology and Allergy chemistry.chemical_classification Binding Sites biology Hemagglutination Antibodies Monoclonal Lectin Hematology Flow Cytometry medicine.disease biology.organism_classification Ulex europaeus Hemolysis Kinetics Red blood cell Hexosaminidases medicine.anatomical_structure Biochemistry chemistry Polyclonal antibodies biology.protein Plant Lectins |
Zdroj: | Transfusion. 35:813-821 |
ISSN: | 0041-1132 |
Popis: | BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates. |
Databáze: | OpenAIRE |
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