Figure 5. Id3^−/− Apoe^−/− B cells have decreased expression of CCR6 and expression of CCR6 on B cells mediates homing to the aorta and atheroprotection.

a, Real time PCR (see Methods for sequences) of B cell mRNA from Id3^−/− Apoe^−/− mice expressed relative to Id3^+/+ Apoe^−/− values. b, CCR6 staining of B cells from Id3^+/+ Apoe^−/−or Id3^−/− Apoe^−/− mice. c, Percent specific migration of B cells in response to 500 ng/ml of CCL20 or 1000 ng/ml of CXCL13. *:p=0.006. d, Luciferase activity from BJAB cells co-transfected with 2.3 kb human CCR6 promoter-luciferase construct and a pEF4 E12, empty pEF4 or pEF4 Id3 expression vectors. Experiments performed in triplicate were repeated 3 times. e, Representative flow plot and f, quantitation of B cell staining within aortas harvested from 10 to 12 week-old C57BL/6 (B6) or Ccr6^−/− mice (n=5) *p=0.032. g, Representative flow plot and h, quantitation of B cell staining within aortas of μMT Apoe^−/− mice 24 hours after adoptive transfer of 60 × 10⁶ splenic B cells from B6 or Ccr6^−/− mice or vehicle control. Each point represents a single animal. *p=0.009. i, Quantitation of en face lesion area of μMT Apoe^−/− mice after adoptive transfer of 60 × 10⁶ B cells from either Ccr6^+/+ Apoe^−/− or Ccr6^−/− Apoe^−/− mice or vehicle control. Animals were fed a Western diet for 16 weeks starting 72 hours after adoptive transfer. Each point represents a single animal. *:p=0.0002, **:p=0.002, n.s. = not significant.