Figure 5. The ITT augments the competitiveness of mIgG-expressing B cells.

Heterozygous male animals whose B cells expressed either wild-type mIgG1^a or YF-mutant mIgG1^b (grey lines) and control animals expressing both allotypes in wild-type configuration (black lines) were immunized with 50 μg ovalbumin in aluminium hydroxide and were boosted the same way 85 days later. On day 232, mice were challenged with 5 μg OVA (w/o alum). The production of OVA-specific IgG1^b (a) and IgG1^a antibodies (b) was determined by ELISA. Data are shown as mean±s.e.m. of 4–6 animals per group. (c) The ratio of IgG1^a to IgG1^b titres was calculated for each animal and is depicted as mean±s.e.m. Black line: wt/wt, grey line: wt/YF. Statistical significance was determined by Mann–Whitney test. *P<0.05, **P<0.01. Data are representative of three independent experiments.