IHC Antibody Features: High Sensitivity

Monoclonal antibodies are traditionally made by fusing myeloma cells with the spleen cells from a mouse that has been immunized with the desired antigen. Using a mouse as a host is cost-effective and easy to manage. However, researchers have seen limitations of mouse monoclonal antibodies. First, Many protein targets are highly conserved between mice and humans, and can therefore be recognized as self-antigens by a mouse host, making them less immunogenic. Second, mouse monoclonal antibodies have low affinities, and thus have a weak attraction to bind to the protein targets. These problems can be avoided when using rabbit as a host animal. The availability of rabbit monoclonal antibodies is highly desirable for their high specificity and affinity, and greatly improved response to mouse antigens. In addition, rabbits are known to produce antibodies to many antigens that are not especially immunogenic in mice. Rabbit monoclonal antibodies also have other advantages, such as more diverse epitope recognition and improved immune response to small-size epitopes, compared with mouse monoclonal antibodies. However, rabbit monoclonal antibodies are much more difficult to develop compared to mouse or rat monoclonal antibodies, due to lack of a stable fusion partner cell line for hybridoma development.

Rabbit monoclonal antibody VS Mouse monoclonal antibody

The K​D (the equilibrium dissociation constant between the antibody and its antigen) value is used to compare the affinity of different antibodies. The lower the value of KD, the higher the affinity.

affinity comparison: rabbit monoclonal antibody vs mouse monoclonal antibody
Rabbit antibody has higher affinity, 10 - 100 folds to mouse antibody!

Rabbit monoclonal antibody features:

  • • More epitopes and diversity
  • • More sensitive and specific than mouse antibody
  • • Better to recognize small molecules
  • • Can produce anti-mouse/rat antibodies

Rabbit monoclonal antibodies offer the best signal-to-noise rate performance

Higher affinity, reduce working concentration

COX5B rabbit monoclonal antibody Rabbit monoclonal antibody

Immunochemical staining of human COX5B in human colon with rabbit monoclonal antibody (5 µg/mL, formalin-fixed paraffin embedded sections).
COX5B mouse monoclonal antibody Mouse monoclonal antibody

Immunochemical staining of human COX5B in human colon with rabbit monoclonal antibody (15 µg/mL, formalin-fixed paraffin embedded sections).

Best signal-to-noise rate, reduce the background

CD3E rabbit monoclonal antibody Rabbit monoclonal antibody

Immunochemical staining of human CD3E in human tonsil with rabbit monoclonal antibody (2 μg/mL, formalin-fixed paraffin embedded sections).
CD3E mouse monoclonal antibody Mouse monoclonal antibody

Immunochemical staining of human CD3E in human tonsil with mouse monoclonal antibody (15 μg/mL, formalin-fixed paraffin embedded sections).