Targeting of CSF-injected DCs to B-cell follicles. To confirm the localization of CFSE-labeled DCs within B-cell follicles, immunostaining of CD3, CD45RA (OX33 expressed on B cells), or MHC class II molecules was performed on sections of cervical lymph nodes obtained from rats killed on day 3 after injection (n = 2). (A-B) Although some CFSE-labeled cells are present in the T-cell area (A), the majority are located within B-cell follicles (B). (C) Immunostaining of MHC class II molecules shows that CFSE-labeled DCs express MHC class II molecules within B-cell follicles of cervical lymph nodes. F indicates follicle. Scale bars: 200 μm (B), 100 μm (A), 50 μm (C), 10 μm (inset in panel C).