Impaired APC movement in inflamed D6-deficient mice. (A) D6-deficient mice show impaired LC trafficking from inflamed skin to LNs. The percentage of LN CD11c⁺ cells that were FITC⁺EpCAM⁺ LC in LNs draining TPA-inflamed skin, 24 hours after FITC application, was assessed by flow cytometry. (B) Representative microscopic images of draining LNs, showing the differential presence of FITC (green)–positive leukocytes in WT and D6-deficient mice. Images were acquired at ×20 magnification on a Plan-Neoplmar 20×/0.5 objective. Scale bar represents 50 μm. (C) FITC intensity (mean fluorescence intensity) of LCs in draining LNs as measured by flow cytometry. (D) Inflammation is required for the impairment of LC migration to LNs in D6-deficient mice. FITC was applied to WT and D6-deficient mouse skin without prior inflammation and FITC⁺EpCAM⁺ LC numbers, in LNs, measured by flow cytometry. (E) Numbers of donor WT (gray) and D6-deficient (black) DCs present in draining LNs of inflamed host as determined by flow cytometry. Data are from 3 (A-C,E) and 2 (D) independent experiments with n > 3 mice per experimental group for each individual experiment.