To produce monoclonal antibodies, individual B-cells are isolated from immunised animals and fused with an immortal (myeloma) cell line to produce hybridoma cells. The hybridoma cells are similarly immortal and hopefully, produce antibodies with the desired specificity. Multiple mouse immunisations and subsequent hybridoma screening are frequently required before clones are identified that produce a suitable monoclonal antibody. Appropriate clones are then propagated in large quantities and the monoclonal antibody is purified from the culture supernatant (Figure 8.1
Monoclonal antibodies recognise a single epitope (Figure 8.2
), and are particularly suited as primary antibodies in ELISA assays, or in competitive immunoassays measuring drugs, hormones or other analytes, in which the antigenic target has a defined structure with minimal variation.