Rabbit Monoclonal Antibodies
Rabbits provide strategic benefits over mice when it comes to producing monoclonal antibodies. The rabbit spleen contains more B cells than the mouse spleen, as the rabbit is larger in size. The more B cells, the more antibodies produced, which translates to a higher chance of finding the ideal clone for expansion.
Antibodies Against a Wider Range of Epitopes
Immunoglobulin genes from rabbits form antibodies that fit a much wider range of epitopes than mouse antibodies. Isoforms of a protein can differ by one amino acid residue, which results in slight variations in structure. The rabbit’s immune system better recognizes these subtle differences, producing monoclonal antibodies. On average, rabbit monoclonal antibodies bind with 10-100 times higher affinity than mouse monoclonal antibodies.
More Small Molecules are Immunogenic in Rabbits Compared to Mice
The rabbit’s immune system is able to mount an immunogenic response to small molecules much more easily than the mouse immune system. When a small molecule with a small epitope is injected into a rabbit and a mouse side by side, the rabbit is more likely to have high titers compared to the mouse, as the rabbit has a more complex immune response.
Immunodominance is when certain epitopes from the same antigen are more immunogenic than others. This results in the immune system producing a great amount of antibodies against the dominantly immunogenic epitope, and few antibodies against the other epitopes. Rabbits exhibit less immunodominance than mice.