FIGURE 2. Effects of GAGs on CXCL12-mediated chemotaxis.
Chemotactic index is calculated as the number of cells migrating in the presence of CXCL12 with or without GAGs ÷ number of cells migrating in the absence of CXCL12. A, chemotaxis of heparan sulfate (0.1 to 100 μg/ml) preincubated with CXCL12 (10 and 100 nm). B, chemotaxis of low and high molecular weight heparin (10 and 100 μg/ml) were preincubated with CXCL12 (10 and 100 nm). Analysis of variance for data gives significance at p = 0.0001. In A, post hoc t tests give p ≤ 0.0008 for the CXCL12 activity at 10 and 100 nm versus background. These activities are inhibited by all concentrations of heparan sulfate tested and the effect is significant for 10 nm (p ≤ 0.009) and 100 nm CXCL12 (p ≤ 0.009). In B, post hoc t tests give p ≤ 0.0003 for the CXCL12 activity at 10 and 100 nm versus background. Both of these activities are significantly inhibited by all concentrations of heparin tested (10 nm CXCL12 is inhibited by 10 and 100 μg/ml of low molecular weight heparin with p ≤ 0.0005 and by 10 and 100 μg/ml of high molecular weight heparin with p = 0.0002 in both cases). 100 nm CXCL12 is inhibited by 10 and 100 μg/ml of low molecular weight heparin with p ≤ 0.0003 and by 10 and 100 μg/ml of high molecular weight heparin with p ≤ 0.0002.