Injected B cells can be recovered in the secondary lymphoid organs and are primarily localized to the follicular regions. C57BL/6 mice were primed with Ad-GP33 and 14 days later, mice were given IV 3 × 106 CFSE-labeled B/VSV-GP33 or DC/VSV-GP33. Spleen (A) and lymph nodes (B) were harvested at 12 and 24 hours, and the number of recovered CFSE+ cells was determined by flow cytometry (n = 3/group). This experiment was repeated twice with similar results. Frozen sections from the same treatments described previously were stained with B220 (red) and imaged using a confocal microscope. (C) A representative of these images at the 24-hour time point. Photographs were taken using a confocal laser scanning microscope (LSM 510 Meta imaging system, Carl Zeiss) with a 10× (spleen) or 20× (lymph node) objective. Fo, follicle.
