A) αIgD induced pS6 signaling (based on the log₂fold increase in MFI in αIgD treated cells relative to the untreated control (0 min)) over time are shown for the African American (AA) and European American (EA) donors. The difference in pS6 signaling (averaged over time points) between racial groups is statistically significant. B) The percentage of CD20+ B cells that were IgD+ is shown for the AA and EA donors. The difference in IgD+ frequency between racial groups is statistically significant. In both (A) and (B), one of the ten donors was excluded due to an insufficient number (<200) of B cells collected for analysis.