Animal spleen hundreds of millions of different B-lymphoblastoid cell lines, with the different genes of different B lymphocytes synthesize different antibodies. When the body by antigen stimulation, many epitopes on the antigen molecule to activate B cells each with a different gene. Activated B cells proliferate to form the effect of B cells (plasma cells) and memory B cells, cloning synthesis of a large number of plasma cells and secrete large amounts of antibody molecules distribution to blood, body fluids. If you elect to create a specific antibody plasma cells were cultured, can be obtained by single-cell proliferation and the formation of the cell populations, ie, monoclonal. Monoclonal cells will synthesize an antigen epitope antibody, called monoclonal antibodies.