FIG. 5.

CCL2 is the main chemotactic factor in the culture supernatants of MVA-infected monocytic THP-1 cells and primary human monocytes. Cell culture supernatants from THP-1 cells (upper panel) and primary human monocytes (middle panel) infected with MVA (MOI of 4 or 0.05, respectively) were placed into the lower part of the chemotaxis unit. Supernatants and rCCL2-containing wells (lower panel) were incubated with anti-CCL2 antibodies or IgG1 isotype control antibodies for 30 min. Naive THP-1 cells were the placed into the upper part. Cells in the lower part were counted after 2 h, and chemotaxis index was calculated as described in Materials and Methods. Data are means ± SEM (n ≥ 4). *, P < 0.05; **, P < 0.01. Ab, antibodies.