Genetic control of the immune response to mammalian chymotrypsins in mice. II. The immune response to low doses of bovine alpha-chymotrypsin.

The immune response to the antigen bovine pancreatic alpha-chymotrypsin was investigated in ten recombinant strains of mice. Using a fixed antigen-percentage bound isotope technique, it was found that the quantity of antibody produced was related to the H-2 haplotype of the responding animal. A continuous distribution for the mean antibody responses was obtained for the ten strains of mice. High responsiveness was associated with the H-2 haplotype gamma2. The genetic control of the immune response to this immunogen was found to be both quantitative and qualitative.