Greater TLR10 expression in IgM+IgD+CD27+ cells from blood and spleen. B cells from blood and spleen were analyzed for TLR10 surface expression by flow cytometry after gating on different CD19+ subsets distinguished by IgD and CD27 labeling. Expression of TLR10 was greater on IgD+CD27+ cells (blue) in comparison with naive IgD+CD27− (gray) and IgD−CD27+ cells (red); the black line represents the isotype-matched control antibody. Data are representative of 6 blood samples and 10 splenic samples. An average 2- and 1.8-fold difference in mean fluorescence intensity was observed for IgM+IgD+CD27+ versus switched B cells from blood and spleen, respectively (P < .002 and P < .004, see “Methods”).