ABSTRACT
Each IgG antibody molecule consists of four polypeptide chains and has two antigen-binding sites. A preparation of antibody molecules that arises from several different clones of cells is called a polyclonal antibody. It is a mixture of antibody molecules that bind to different parts of the antigen and with different binding affinities. Monoclonal antibodies produced using this technology is common tools in research because of their very high specificity. Antibody produced by a single clone of cells is a monoclonal antibody; all the antibody molecules are identical and bind to the same antigenic site with identical binding affinities. The problem is that if an individual antibody-producing cell is isolated and grown in culture, its descendants have a limited life-span that severely limits their use for the routine preparation of monoclonal antibodies. Monoclonal antibodies produced using the technology is common tools in research because of their very high specificity.
