title: Competitive binding of a monoclonal antibody SZ-21 with anti-PLA1 antibodies and its potential for clinical application.
abstract: Both intact IgG and Fab fragments of a monoclonal antibody SZ-21, directed against platelet glycoprotein (GP) IIIa, inhibited binding of anti-PLA1 antibodies to PLA1-positive platelets in a dose dependent manner. Conversely, the binding capacity of the platelets for SZ-21 was decreased in the presence of anti-PLA1 antibodies. In Western blots, the determinant for SZ-21 was present on GPIIIa from either PLA1 or PLA2 homozygotes, but SZ-21 did not affect the interaction of anti-Yukb alloantibodies with their target antigen on GPIIIa. These results suggest that SZ-21 reacts with an epitope on the GPIIIa molecule very close to but not identical with that for anti-PLA1. The existence of PLA1-reactive alloantibodies in serum could be demonstrated by their competitive effect on the binding of SZ-21.
authors.affiliation: Jiangsu Institute of Hematology, Suzhou Medical College, People's Republic of China.
authors.forename: X
authors.initials: X
authors.lastname: Xi
authors.forename: Y
authors.initials: Y
authors.lastname: Zhao
authors.forename: H
authors.initials: H
authors.lastname: Jiang
authors.forename: Q
authors.initials: Q
authors.lastname: Wu
authors.forename: P
authors.initials: P
authors.lastname: Li
authors.forename: C
authors.initials: C
authors.lastname: Ruan
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000627:therapeutic use; D001667:Binding, Competitive / Q000276:immunology; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology; D006801:Humans; D007518:Isoantibodies / Q000097:blood / Q000276:immunology*; D010980:Platelet Membrane Glycoproteins / Q000276:immunology; D017186:Titrimetry
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D007518:Isoantibodies; D010980:Platelet Membrane Glycoproteins