Fig. 2.

Effect of cobalt ions on monocyte chemotaxis. A. Filters stained with haematoxylin showing migrated monocytes at ×40 magnification. B. Migrated monocytes were counted at ×40 magnification. There was a significant increase in monocyte migration in response to 0.75 mM CoCl₂ and 100 ng/ml LPS (24 h treatment) conditioned media compared to untreated controls. 1 µg/ml CLI-095 abrogated the CoCl₂-induced effect (P<0.001). The effect of LPS was also inhibited demonstrating that the antagonist is specific for TLR4. CLI-095 had no effect on migration in untreated controls (P=0.78). Data is representative of three independent experiments each using a different monocyte donor. ***=P<0.001, Student's t-test.