Comparing gene expression in CD5+CD1dhigh and CD5-CD1dhigh B cells

We have previously observed that regulatory B cells expressing the apoptosis-inducing surface molecule Fas ligand were enriched in the B cell fraction denoted by a surface phenotype of CD5+CD1dhigh. To identify potential growth factors, transcriptional regulators, or surface markers that might better characterize regulatory B cells, we compared global gene expression by microarray in two B cells subsets isolated by FACS. Splenocytes from 20 DBA/1 male mice were harvested, pooled, and CD19+ B cells were isolated by positive selection using MACS. B cells were then stained for CD5 and CD1d and sorted by FACS into CD5+CD1dhigh and CD5-CD1dhigh populations. Single replicates of both CD5+CD1dhigh and CD5-CD1dhigh B cells from pooled mouse splenocytes were isolated and assay using the Affymetrix GeneChip Mouse 430 2.0 Array.