Figure 7.

αRP105-TM can activate both immature and mature B cells depending on RP105. (A) HEK293T cells were transfected with pCADEST1-empty (Vector) or pCADEST1-anti-RP105 kappa-F2A-anti-RP105 mIgG1-TM [αRP105-TM (F2A)]. Two days later, the splenocytes that were obtained from RP105-Hetero and RP105-KO BALB/c mice were co-cultured with HEK293T cells for 2 days. The splenocytes, which were gated on B220, were also incubated with biotinylated parental anti-RP105 mAb (rat) or anti-CD86 antibodies as indicated, followed by incubation with PE-conjugated streptavidin. (B) The splenocytes, which were gated on IgM^low IgD^high as mature B cells (Middle panel) or IgM^high IgD^low as immature B cells (Right panel), were also incubated with biotinylated anti-CD86 antibodies, followed by incubation with PE-conjugated streptavidin. The indicated numbers on each gate (Left panel in B) respectively represent the percentage of cells of mature or immature B cells gated on B220⁺ cells. The numbers in the histogram represent MFI. The expression level was analyzed using a BD LSRFortessa. All indicated data are representative of two independent experiments.