Monoclonal antibodies (mAbs) are monovalent (one epitope) antibodies derived from clones of a single parental immune cell. The original method for producing monoclonal antibodies is found in hybridoma technology. Prior to the production of monoclonal antibodies, polyclonal antibodies (multiple epitopes, multiple parental cells) were the standard for in vitro research. Production of polyclonal antibodies, however, was too inconsistent to be an effective tool for in vivo research. The breakthrough came in the 1970s, when Kohler and Milstein succeeded in creating the first hybridoma cell line. They were awarded the Nobel Prize for Medicine and Physiology in 1984.
Hybridoma technology involves immunizing a host animal with an antigen of interest to elicit an immune response. When a sufficient response is achieved as determined by in vitro testing, the mature B-cells are harvested from the animal spleens. The B-cells are then fused with myeloma cells using polyethylene glycol (PEG) to generate an immortalized hybridoma cell line. Through multiple rounds of screening, a single, pure, hybridoma positively-expressing the antibody against the antigen of interest, as determined by ELISA, is amplified and monoclonal antibodies are purified.
Due to their high target affinity, monoclonal antibodies have a wide range of diagnostic and therapeutic uses. They are employed in the detection of the target antigen/protein in ELISAs, Western Blots, and in tissue sections inimmunohistochemistry. Monoclonal antibody therapy is employed in the prevention and/or treatment of infection by Respiratory Syncytial Virus (RSV) and Ebola or as immunotherapeutics for such illnesses as rheumatoid arthritis, and cancers.