From an exposure to antigens
From an exposure to antigens, antigenic molecules have several epitopes which result in synthesis of a mixture of antibodies. Each B-cell synthesizes a specific antibody. But antigens which contain multiple epitopes stimulate a series of B-cells which ultimately result in multiple cloning of plasma cells that are responsible for synthesizing different specific antibodies. This is termed as polyclonal activity. In 1975, Kohler and Milstein gave a concept of “one lymphocyte-one antibody” in the form of hybridoma. Each lymphocyte produces only one type of antibody for a specific antigenic epitopes and termed as monoclonal antibody. For unlimited supply of this monoclonal antibody, proper clone of B-cells and for harvesting pure monoclonal antibodies should be done by artificial means. This monoclonal antibody is produced by using a technology called “Hybridoma technology” which was discovered by George Kohler of West Germany and Cesal Milstein of Argentina in 1975.
In this technology, immortal hybridomas which are cell fusion of B-cells and myeloma cells are grown on artificial medium. These are further veiled for production of antibody specifically monoclonal antibodies for large scale. This technology for monoclonal antibody production opens a vast area of application specifically in medical sciences.
The fundamental of hybridoma technology is based on the immortalization of B lymphocyte cells having antibody producing capacity but limited growth characteristics in vitro. The lymphocytes are fused with cells from a non-antibody producing and myeloma (continuously growing tumor cell line), as the hybrids continue to secrete antibodies while gaining the immortality of the parent tumor cells. So monoclonal antibodies are ‘hybrid’ cells that are created by the fusion of two cells, which is a myeloma cell with genetic potential of multiplication characters, and another cell that has a gene that codes for the targeted antibody.