(A) Representative cross-sections of draining LNs (dLNs) from mice 7d post immunization with HEL-OVA/CFA following adoptive transfer of BHEL and transduced CD4OT-II cells. dLN were cryosectioned and stained with fluorophore-conjugated antibodies against GL-7 to reveal GCs (green), CD21/35 to stain for follicular dendritic cells (FDC, red) and Hoechst to stain for cell nuclei (blue). Scale bar, 250µm. (B, C) Quantification of the number of GCs relative to B cell follicles (B) and size of GC (C) on confocal micrographs as shown in A. Shown are mean values with SD from dLNs from three mice in two independent experiment. Each dot represents one LN (3 LNs/mouse) in B and one GC in C. 