monoclonal or polyclonal

Monoclonal or Polyclonal Antibodies: The Best Choice for Your Research

Introduction to Antibodies

Plasma cells are specialised B lymphocytes that secrete antibodies (glycoproteins) in response to infection by antigens (toxins or foreign substances). Antibodies, also known as immunoglobulins (Ig), usually have a high affinity to a specific antigen, binding only to one epitope/binding site on an antigen. Monoclonal (Mab) or polyclonal (pAb) antibodies are used in scientific research for a wide range of applications. This article will guide your choice for your research.

Choosing between Monoclonal and Polyclonal Antibodies

Both monoclonal and polyclonal antibodies have specific features, it is important to choose the right antibodies for your research.

  • How will the antibodies be used in your research?
  • What do you need to achieve?

What are Monoclonal antibodies (MAb)?

Monoclonals are an immortalised hybridoma cell line, a vital research tool since 1975. Monoclonals can detect a single protein or can be used as a probe to locate the protein in vivo. MAbs are created by fusing a single splenic B cell with a myeloma cell, the clones produced are purified from the cells or the lysates and are capable of binding to a single type of epitope. Generation of large enough quantities to purify requires skill and takes up to 12 months, therefore they are more expensive.

What are Polyclonal antibodies (PAb)?

Polyclonal antibodies are derived from different B cells. They can bind to more than one epitope on an antigen. PAbs are created in the serum of an immunised animal, usually goat, sheep, rabbit. The host animal generates multiple B cell clones against every epitope on the antigen. Polyclonal antibodies will have variability across batches, they are quicker and cheaper to produce. This is useful if you are not looking for a specific epitope or your epitopes may have become distorted. Polyclonal antibodies could potentially amplify your signal.

Advantages of Monoclonal and Polyclonal Antibodies in Research

Your choice of monoclonal or polyclonal antibodies will be dictated by the aims of your research.

Monoclonal Antibodies
FeatureAdvantage
Specificity for one Epitope Locating a specific antigen
Consistency and binding efficiency Reproducible, predictable results. Good for assay, therapy production and all diagnostic applications
Purified from immortal cell lines Long term source, stability, repeatability
Can be cleaved to reduce nonspecific Fc binding Useful in flow-cytometry
Large quantities of identical antibodies can be produced Reproducible, predictable results for diagnostic and manufacturing applications

Polyclonal Antibodies
FeatureAdvantage
Recognise and bind to multiple epitopes More robust for assaying epitopes with slight variations. Useful in Western Blot, IP and ChIP
Large quantities easily generated Detection of target antigen is maximised but can create background signal
High antigen detection rate Useful if consistency over long time periods is not important
Can amplify signal Useful for low target epitope levels
Can capture target protein quickly Useful as capture antibody in Sandwich ELISA and in IP or ChiP
Can detect native proteins Best choice for multiple assay types
Can be conjugated with antibody labels easily Binding affinity is less affected than it would be in MAbs

Summary

If you require a large quantity of identical antibodies that will bind to one specific epitope, monoclonal antibodies are the best choice. Monoclonals are well suited to diagnostic or manufacturing applications and for therapy and assay production because of their consistency and stability. If it is more essential to increase the chances of detecting your target antigen, choose polyclonal antibodies.