Antibody against metalloproteinase-2 (MMP-2) inhibits CCL1- and LCM-induced chemotaxis of VSMCs. Mixtures of CCL1 (100 ng/mL) and goat IgG or goat anti–MMP-2 (> MP2) or anti–MMP-9 (> MP9) (1 μg/mL) were added to the bottom wells of the chemotaxis chamber. Similarly, LCM, produced as detailed in the legend to Figure 3, was added in the presence of the same immunoglobulin preparations. The chemotactic activity of these mixtures was tested against VSMCs as detailed in “Materials and methods.” Anti–MMP-2 inhibited chemotaxis induced by CCL1 74.5% and by LCM 95% (*P < .0001), whereas anti–MMP-9 was less effective, inhibiting CCL1- and LCM-induced chemotaxis 32.6% and 41.6%, respectively (**P < .03). Inhibition of VSMC chemotaxis by antibody against MMP-2 was significantly greater than by anti–MMP-9 (P < .007). These studies suggest that MMP-2 is the principal metalloproteinase involved in the chemotaxis of VSMCs in response to either CCL1 or LCM on a fibronectin-coated surface. M indicates DMEM. Error bars represent SD.