αGalCer treatment limits MZB expansion in NOD mice.

<p><b>A</b>. Spleen cells from NOD or normal BALB/c mice were analyzed for MZBs. Comparison of MZB frequency between NOD and BALB/c mice (n = 6 NOD and 3 BALB/c mice, 8–10-week-old females). Numbers on dot plots indicate MZBs (CD21^hiCD23^−/low) as the mean ± S.E. % of CD19⁺ cells (*p<0.001). Bar diagram shows the mean ± S.E. absolute numbers of MZBs per spleen (*p<0.001). (<b>B, C</b>) Spleens were harvested from 2-mo-old NOD or C57BL/6 mice at 3 d after a single i.p. injection with αGalCer or vehicle (n = 6 mice per group). <b>B</b>, Cells were analyzed for MZBs as CD21^hi CD23^−/low CD1d^hi CD9⁺ cells on gated CD19⁺ B cells. Numbers on dotplots indicate MZBs as % of CD19⁺ B cells. Bar diagrams show the mean ± S.E. % MZBs in NOD mice. Compared to vehicle-injected mice, αGalCer-treated NOD mice had a significant reduction in MZBs, defined as CD19⁺CD21^hiCD23^−/low (p = 0.007), CD19⁺CD21^hiCD1d^hi (p = 0.0001), CD19⁺CD1d^hiCD9⁺ (p = 0.009). <b>C</b>, Frozen spleen sections were stained for APC-IgM (blue) and FITC-MOMA1 (green). Confocal images at 20× and 40× magnification show the reduced thickness of marginal zone (MZ) IgM⁺ cells (blue) in αGalCer-treated mice (as indicated by blue arrows). Data represent three independent experiments.