Fig. 3

IgA class-switch of tonsil IgM⁺ B cell subpopulations in response to T-dependent and T-independent stimulation. IgM⁺IgD⁺CD27⁻, IgM⁺IgD⁺CD27⁺, IgM⁺IgD⁻CD27⁻, IgM⁺IgD⁻CD27⁺, were FACS-sorted and stimulated with CpG DNA or anti-LC + anti-CD40. Secreted IgA was measured by CBA on day 7 after stimulation. Results are presented as mean ± SEM; two-tailed unpaired Student’s t-test, n = 7, ^*P < 0.05, ^**P < 0.01. Gating strategy for cell sorting (Supplementary Fig. 5).