Figure 4: Themis2 is required for B cell selection by self and foreign antigen.
From: Themis2 lowers the threshold for B cell activation during positive selection
(a) Numbers of B cell subsets in the BM and spleens of wild-type, Themis2+/− and Themis2−/− IgHEL transgenic mice (gated as in Fig. 2). Symbols represent individual mice and bars represent means and s.e.m. (b,c) Phenotype and enumeration of peritoneal B cells from wild-type and Themis2−/− IgHEL and IgHEL-mHELKK mice showing the flow cytometry gating (b) and enumeration (c) of HEL-binding B220hiIgMa+ follicular B cells in IgHEL mice (left histograms and upper graphs) and B220loIgMa hi B1 B cells in IgHEL-mHELKK mice (right histograms and lower graphs). Columns show means and s.e.m. and data are representative of three experiments (n > 10). (d) Serum anti-HEL IgMa in adult wild-type and Themis2−/− IgHEL and IgHEL-mHELKK mice. Symbols represent individual animals and bars show means and s.e.m. (e) Wild-type B6 mice were injected intravenously with 50:50 mixtures of CD45 allotype-marked WT:WT or WT:Themis2−/− IgHEL B cells and OT-II T cells and immunized with OVA-HEL/RIBI 1 d later. Flow cytometry shows typical gating of GC B cells at 8 d and their resolution into HEL+CD45.1 (wild-type) and HEL+CD45.2 (wild-type or Themis2−/−) cells. (f) Percentage of wild-type or Themis2−/− HEL+CD45.2 GC B cells at input and in the GC 8 d after immunization. Columns show means and s.e.m. and symbols represent individual mice at 8 d or separate input samples. Data were combined from three experiments and compared by unpaired t test. *P < 0.05, **P < 0.01 and ***P < 0.001.
