Noxa ablation results in survival of multiple B cell clones after immunization. Mice were immunized with PE and after 12 days, antigen-specific germinal center B cells were sorted and analyzed for clonal diversity. Pooled data of 3 mice per genotype from 2 independent experiments were used. (A) Representative phylogenetic trees of antigen-specific cells from a WT (left) and Noxa^−/− mouse (right) shows increased clonal diversity within the latter. (B) CDR3 lengths of PE specific clones (AA indicates amino acids). (C) Interclonal diversity as a percentage of divergence between all pairs of sequences from a multiple alignment (WT n = 73, Noxa^−/− n = 93; ***P < .0001; Student t test and Mann-Whitney test).