The effect of antigen doses and time intervals between antigen injections on secondary, tertiary and quaternary antibody responses. Establishment of hyperimmunization with bovine serum albumin in mice treated with capsular polysaccharide of Klebsiella pneumoniae.

Injection of bovine serum albumin (BSA) with the capsular polysaccharide of (CPS-K) as adjuvant strongly primes mice for booster injections of BSA alone. The best doses of antigen for booster injections varied according to the frequency of antigen injections and the time interval between antigen injections. Increase in memory following the injection of BSA mixed with CPS-K adjuvant was first detected 10 days later. Memory continued to increase as the time interval after priming was increased to 90 days. Memory for the tertiary response increased after the optimum secondary antigenic stimulus. Increase in memory after the secondary antigenic stimulus was detected as early as 7 days after injection. Even secondary injection of the high dose of 50 mg of BSA did not exhaust immunological memory. Memory was also increased after the tertiary antigenic stimulus. Extremely high antibody responses (up to 49.2 mg protein per ml of antibody) could be obtained by eliciting tertiary and quaternary antibody responses optimally at the time memory was developed to the maximum level.