B-cell–DC cocultures induce CD11c⁺ cell maturation and increase cell division. Splenic CD11c⁺ cells were purified by FACS sorting and CFSE-labeled prior cocultures with B cells. CD11c⁺ cells alone have been used as control in these experiments. After 72 hours cells were collected and analyzed for cell division and expression of the CD86 maturation marker. Splenic CD11c⁺ were analyzed for purity after FACS sorting (A). SSC indicates side scatter. CFSE dilutions are shown in panel B, where B-cell–DC cocultures are represented by solid histograms and DCs alone by dotted histograms. Confirming previous results, CD86 was expressed in the large majority of the CD11c⁺ cells cocultured with B cells (C, top right quadrant). As expected, DC induced B-cell maturation through BLyS (C, top left quadrant).