Germinal center formation in BSA-tolerant chickens.

In chickens rendered neonatally tolerant to BSA the germinal center formation was significantly decreased after stimulation with BSA at the age of 3 weeks. At the breakdown of tolerance after the age of 6 weeks the IgG antibody formations recovered before the IgM production. Stimulation of tolerant birds with unrelated antigens resulted in slightly decreased antibody response but the germinal center formation was on the same level as in normal controls.