Monoclonal Antibodies

This lesson covers:

  1. What monoclonal antibodies are
  2. The uses of monoclonal antibodies in medicine
  3. The hybridoma method for producing monoclonal antibodies 

Monoclonal antibodies

Monoclonal antibodies are antibodies produced from a single clone of plasma cells:

  • 'Mono' means single.
  • 'Clonal' means clone.


Each of these antibodies are identical to one another and so will bind to a specific molecule.


Monoclonal antibodies have many uses: 

  • Diagnosis of disease - Monoclonal antibodies bind to specific cell types to identify infected cells. 
  • Treatment of disease - Monoclonal antibodies bind to specific cells, bringing therapeutic drugs with them.
  • Pregnancy testing - Monoclonal antibodies bind to a pregnancy hormone in home pregnancy testing kits. 
  • Detecting certain cancers - For example, monoclonal antibodies can bind to prostate specific antigens (PSA) to identify prostate cancer in men.

Hybridoma method

One of the problems with producing monoclonal antibodies is that B cells that divide by mitosis do not produce antibodies and plasma cells that do produce antibodies do not divide.


To overcome this, plasma cells are fused with cancer cells to produce a hybridoma cell. The resulting hybridoma cell divides by mitosis and secretes antibodies. 

Diagram showing the hybridoma method with antigen introduction, plasma cell fusion with cancer cells, and antibody production.

A mouse is injected with a specific antigen. This stimulates plasma cells to produce antibodies against this antigen. These plasma cells are extracted from the mouse's spleen.