FIG. 4.

Cell type specificity of CDV replication and cytokine response. (A) FACS analysis of the percentage of CDV-positive PBMC isolated from animals infected with 5804P, Cko, or Vko at 3, 7, 10, or 14 days p.i. (B) FACS analysis of CDV infection frequency in different cell types from two hosts. One ferret was infected with 5804P (upper row); the other was infected with Vko (lower row). The percentile of cells in each quadrant is indicated in the outer corners. The signal levels observed with phycoerythrin (PE)-labeled antibodies against cellular markers CD3 (T cells), CD79α (B cells), and CD14 (monocyte lineage) were plotted on the y axis; those obtained with the fluorescein isothiocyanate-labeled CDV antiserum (FITC) were plotted on the x axis. (C and D) Percentages of different cell types infected 0 to 21 days after inoculation with 5804P or Vko. Cell type-specific markers are as described for panel B. T cells are shown in red, B cells in are shown green, and monocyte-lineage cells are shown in blue. Lighter shades represent CDV-positive cells; full shades represent CDV-negative cells. The means of the results from three animals are indicated. (E) Representative cytokine responses elicited by 5804P and Vko. Day 3 results are shown with lighter shades, day 7 results with full shades. IFN-α, alpha interferon; IFN-γ, gamma interferon; TNF-α, tumor necrosis factor alpha.