BM-LC from wild-type mice express CD8 when they reach the LN of a CD8α knockout mouse.

(A) 3 × 10⁶ sorted CD8⁻CD11c⁺IA-b⁺ BM-LC were injected subcutaneously into the footpad of a CD8α knockout mouse. Twenty-four hours later, the draining LN were harvested, sectioned, fixed in acetone, and stained with biotin-labeled anti-CD8 antibody followed by streptavidin–PE and FITC-conjugated anti-CD11c. Tissue was analyzed by confocal microscopy. CD8⁺ cells (red), which correspond to the injected BM-LC, coexpress CD11c (yellow). Magnification, 20×. (B) Contour plots show CD11c versus IA-b profiles of a DC-enriched population isolated from the draining and nondraining LN of a CD8α knockout mouse injected subcutaneously with BM-LC generated from wild-type CD8 mice. Histograms show the phenotypes of the CD11c⁺ IA-b⁺DC-enriched cells. Twenty-four hours after injection, DC expressing CD8 were detected in the draining LN, whereas no CD8⁺ cells were detected in the contralateral (nondraining) LN. Identical results were obtained in 2 separate experiments.