Differences in the maturation of the immune response of A- and A+ rabbits. Good and poor responders respectively for the A antigen.

The amount, avidity and specificity of anti-A antibodies produced by rabbits having the A substance in their secretions (A+) and rabbits lacking this antigen (A-), were studied with a series of antigens chemically related to the A substance. Both A- and A+ rabbits produced specific anti-A antibodies but the amount, maturation of avidity and specificity of these antibodies was completely different. These results suggest that the difference between the immune response of A+ and A- animals is not based on a genetically determined inability of A+ rabbits to recognize the self antigen, but rather on differences in the regulatory mechanism(s) controlling the maturation process of the anti-A response.