Patent ID: 7993864

Claim:
A homogeneous assay for identifying an antibody producing cell that produces an antibody that binds to a selected antigen comprising: providing a population of antibody producing cells; incubating on a microscope slide the population of antibody producing cells with an antigen, said antigen being coupled to an erythrocyte or a particle, or said antigen being expressed on the surface of a cell, and a labeled anti-antibody antibody wherein the anti-antibody antibody distinguishes antibody producing cells that produce an antibody that binds to the selected antigen from antibody producing cells that do not and wherein the anti-antibody antibody binds to all antibodies produced by the antibody producing cells, regardless of their binding specificity; and without performing any wash steps, identifying an antibody producing cell that produces an antibody that binds to the selected antigen by detecting the increased concentration of labeled anti-antibody antibodies surrounding said antibody producing cell.