Wild-type mice were nasally immunized with TNP-LPS with or without nCT, nCT alone or PBS. (A) Five days after immunization, mononuclear cells were isolated and stained for CD5, B220, TACI, BCMA and BAFF using the respective fluorescence-conjugated mAbs as described in the Materials and Methods section. Samples were then subjected to flow cytometric analysis by FACSCalibur®. *p<0.05 when compared with mice given TNP-LPS or nCT alone. The values are presented as the mean ± SEM of 10 mice for each group and represent a total of five separate experiments. (B) B-1 B cells were purified by FACSAria from SMGs, NPs and NALT of mice given nasal TNP-LPS with or without nCT two days after the immunization. The expression of TACI, BCMA and BAFF-R mRNA by B1-B cells was assessed by quantitative real-time PCR. Relative expression of TACI, BCMA and BAFF-R mRNA are displayed as the fold change of respective transcript expression by the experimental group (TNP-LPS plus nCT) over the expression by controls (TNP-LPS alone). The values are presented as the mean ± SEM of 10 mice for each group and represent a total of five separate experiments.