Figure 7.

Survival of MBCs is dependent on IKK2. (A) Mixed bone marrow chimeras were generated by reconstituting irradiated Rag1^−/− mice with 10% bone marrow from Ikk1^+/+RCE or Ikk1^fl/flRCE (CD45.1⁻CD45.2⁺) and 90% WT bone marrow (CD45.1⁺CD45.2⁺) for 42 d. Mice were immunized with NP-CGG in alum or alum alone on day 0, boosted with NP-CGG in PBS or PBS alone on day 21, and injected with anti-CD40L on days 43, 45, and 47, followed by five daily tamoxifen injections. (B) Mean (±SEM) numbers of total CD45.1⁻CD45.2⁺ B cells (CD138⁻B220⁺), NP⁻ IgG1⁺ MBCs, and NP⁺ IgM⁺ and IgG1⁺ MBCs (CD138⁻B220⁺Fas⁻PD-L2⁺) in spleens of mice immunized with NP-CGG in alum (+; n = 19 for Ikk1^+/+RCE and n = 17 for Ikk1^fl/flRCE) or alum alone (−; n = 6 for Ikk1^+/+RCE and n = 4 for Ikk1^fl/flRCE) were gated as shown in Fig. 4 B. (C) Mixed bone marrow chimeras were generated by reconstituting irradiated Rag1^−/− mice with 10% bone marrow from Ikk2^+/+RCE or Ikk2^fl/flRCE (CD45.1⁻CD45.2⁺) and 90% WT (CD45.1⁺CD45.2⁺) bone marrow for 42 d. Mice were immunized with NP-CGG in alum or alum alone on day 0, boosted with NP-CGG in PBS or PBS alone on day 21, and injected with anti-CD40L on days 43, 45, and 47, followed by five daily tamoxifen injections. (D) Mean (±SEM) numbers of total CD45.1⁻CD45.2⁺ B cells, NP⁻ IgG1⁺ MBCs, and NP⁺ IgM⁺ and IgG1⁺ MBCs in spleens of mice immunized with NP-CGG in alum (+; n = 16 for Ikk1^+/+RCE and n = 17 for Ikk1^fl/flRCE) or alum alone (−; n = 4) were gated as shown in Fig. 4 B. Each dot represents one mouse. Data pooled from three (B) and two (D) independent experiments. Mann-Whitney test was used for statistical analysis. **, 0.001 < P < 0.01; ***, 0.0001 < P < 0.001; ****, P < 0.0001.