Figure 2. BCR responsiveness of FO B cells expressing different levels of surface IgM.
(A) Representative Ca2+ traces of mature FO B cells (B220pos CD23hi CD24int) expressing low (green), intermediate (blue), or high (red) levels of sIgM following stimulation with GαMμ (2.5 μg/ml). Inset shows representative gating of IgMlo and IgMhi populations, each comprising 10% of the population, for all panels shown in this figure. (B) FO IgMlo B cells stimulated with increasing concentrations of GαMμ (2.5, 10, 25 and 50 μg/ml) in comparison to anergic Ars/A1 B cells (solid black line) stimulated with GαMμ (50 μg/ml). (C and E) Ca2+ mobilization by mature FO B cells expressing low (green) or high (red) levels of sIgM upon stimulation with GαMδ. (D and F) Ca+2 mobilization of mature FO B cells expressing low (green) or high (red) levels of sIgM upon stimulation with GαMκ. Data are representative of 3 or more independent experiments per panel.
