Figure 1.

Ca²⁺ mobilization triggered by MCP-1, CCR2–02 mAb, or crosslinked CCR2–02 Fab. Induction of Ca²⁺ mobilization was promoted by 10 nM MCP-1 (Peprotech) alone or in the presence of PTX (A and D, respectively), 15 nM CCR2–02 mAb (B and E), and 1 μg/ml of CCR2–02 Fab plus 50 μg/ml of rabbit anti-mouse IgG Fab (C and F) in Mono Mac 1 cells loaded with Fluo-3,AM, as described. Results are expressed as a percentage of the chemokine-induced calcium response. Shown are the results of one representative experiment of five performed. (G-I) Ca²⁺ mobilization promoted by 1 μg/ml of CCR2–02 Fab alone, 50 μg/ml of rabbit anti-mouse IgG Fab alone, and 1 μg/ml of isotype-matched control Fab plus 50 μg/ml of rabbit anti-mouse IgG Fab. Fab and anti-Fab antibody were added sequentially; cells were washed between treatments. Arrows indicate stimulus addition.