Figure 1. Selection steps during B-cell development. B-cell development is impaired at Pro-B to pre-B differentiation stage and/or transitional to mature stage in various gene targeted and immunodeficient mice.

Figure 2. B-cell receptor (BCR)-induced signalling pathways.

Figure 3. PIP₃ phosphorylation and dephosphorylation pathways.

Figure 4. Differentiation of splenic B cells in T cell-dependent antibody responses. B cells differentiate along either extrafollicular or follicular pathways. In the extra follicular pathway, activated B cells differentiate into low-affinity short-lived plasma cells. In the follicular pathway, B cells migrate into follicle to form GC, where they differentiate into high-affinity memory B cells or long-lived plasma cells.

Figure 5. Model of class switch recombination and the schematic structure of mouse IgM and IgG1. IgM is produced while the Ig gene is in the germline organization after the VDJ recombination (shown as thick arrows). During the CSR, germline transcripts are produced from the upstream of the switch regions (shown as thin arrows). RNA transcribed by RNA polymerase (RNAP) remains bound to DNA in the R-loop. The region between S and S1 is then deleted by functions of AID and additional cofactors.