What difference between Monoclonal vs Polyclonal Antibodies?

While both monoclonal and polyclonal antibodies can be used in a wide variety of applications including Western blot, enzyme-linked immunosorbent assays (ELISA), immunoprecipitation, immunofluorescence, immunocytochemistry, Biochip technology and in the diagnosis of disease, they each have their own advantages which make them useful for different applications. To determine which type of antibodies should be used for a particular application, let us try to understand the difference between the two.

Monoclonal antibodies (mAbs) represent a population of antibodies that recognize a single epitope within an antigen. Since mAbs are produced from a single B cell in the spleen or lymph nodes of an immunized mouse, the resulting antibodies are all identical. In addition, they recognize the same epitope of a specific antigen.

However, while B cells can be used to harvest antibodies, these cells have a limited lifespan and will eventually stop producing the antibody in time. To overcome this limitation, a specific antibody-producing B cell is fused with a myeloma cell to create an immortalized B cell-myeloma hybridoma which can provide a constant supply of highly specific monoclonal antibody.

Monoclonal antibodies can be raised against many targets. Specific antibody characteristics (sensitivity requirements and cross reactivity levels) can be identified and monoclonal antibodies screened to identify any cell lines exhibiting the required characteristics.

Monoclonals can also be generated to cross react with a group of molecules. This can be quite useful in cases where there are multiple possible combinations of drugs to be tested in a patient.

Monoclonals are typically rat or mouse monoclonals, but they can also be generated from various species such as rabbit and goat.