Studies on the control of antibody synthesis. VI. Effect of antigen dose and time after immunization on antibody affinity and heterogeneity in the mouse

The effect of antigen dose and time after immunization on the affinity of serum antihapten antibody was studied in the mouse by the Farr technique and by equilibrium dialysis. A progressive increase in affinity was seen with time after immunization at all antigen dose levels. The rate of increase in affinity was faster with lower doses of antigen. However, the increase in affinity continued for a longer time in animals immunization with larger doses of antigen. Consequently, at 3 months after immunization animals injected with a larger dose of antigen had higher average affinity antibody than did animals immunized with low doses of antigen. Low affinity antibody was produced in significant amounts at all immunizing dose levels and was present throughout the course of the immune response. Certain technical problems in interpretation of equilibrium dialysis data are discussed.