Antibodies are defined as monoclonal when they are produced by a clone of identical cells originally grown from a single antibody-producing cell. Every immunoglobulin molecule produced by such a hybridoma clone will behave exactly the same and will react with only one identical target. Immunoglobulin Structure Basic immunoglobulin structure comprises a Y-shaped protein consisting of 2 'heavy' chains of 50 kDa each and 2 'light' chains of 25 kDa each. IgA is a dimer of two 150 kDa units joined together, while IgM is a pentamer. The immunoglobulins are then separated from the rest of the culture medium components by passage down chromatography columns which have a high affinity for antibody molecules.
Pure antibody is eluted after all other unwanted proteins have been washed away.