Method and apparatus useful for detecting bloodgroup antigens and

Abstract

The present invention is a method and apparatus useful for the detection of bloodgroup antigens and antibodies. There are two preferred embodiments of the method: a direct assay and an indirect assay. The direct assay comprises adding a sample of erythrocytes to a reaction tube charged with a column of immunoreactive particles having an immunoglobulin binding ligand selected from the group consisting of Protein A, Protein G, Protein A/G or a universal kappa light chain binding protein coupled to the surface of the particles. Antibodies specific for bloodgroup antigens tested for are coupled to the ligand on the particles. The reaction tube is then centrifuged for a time sufficient to force to the bottom of the reaction tube erythrocytes that do not attach to the antibodies on the particles. The indirect assay comprises obtaining either a sample of erythrocytes or a sample of blood serum to be tested and mixing the erythrocytes or serum with a known antibody or antigen reagent, depending on whether antigens or antibodies are being tested for. The mixture is incubated in a reaction tube above a column of immunoreactive particles having immunoglobulin binding ligands selected from the group consisting of Protein A, Protein G, Protein A/G or a universal kappa light chain binding protein coupled to the surface of the particles. The reaction tube is centrifuged for a time sufficient to force to the bottom of the reaction tube erythrocytes that do not attach to the ligands on the particles. The response is the same regardless of whether a direct or indirect assay is performed.