Figure 3.

CD11c ⁺ blood‐derived macrophages in MHV‐J2.2v‐1‐infected mice variably exhibit properties of immature APCs. Leukocytes were prepared from the CNS of J2.2v‐1‐mice at 9 days p.i. and analyzed by flow cytometry. Macrophages were identified as CD45^hiF4/80⁺. A. Representative histograms of CD40, CD86 and MHC class I, and class II antigen expression on CD11c⁺ (filled) and CD11c^‐ (open) cells are indicated. Isotype‐matched control antibodies are also shown (dashed line). B. MFI of CD40, CD86 and MHC class I and class II antigen are shown (3–4 mice per group; mean ± SEM). C. Representative histograms depicting FITC‐Dextran uptake by CD11c⁺F4/80⁺ (left panel) and CD11c⁺F4/80^‐ cells (middle panel). F4/80‐ cells (right panel) are depicted as a negative control for uptake. Cells isolated from the CNS were incubated with FITC‐Dextran at 4°C (dotted line) or 37°C (solid line) for 1 h, then analyzed by flow cytometry for FITC‐Dextran uptake, and CD45, F4/80 and CD11c expression. D. Mean ± SEM of five mice per group of the fold increase in MFI of cells analyzed under optimal and control conditions for FITC‐Dextran uptake (37°C:4°C). Abbreviations: APC = antigen‐presenting cell; FITC = fluoroscein isothiocynate; MFI = mean fluorescence intensity.