Fig. 4. Effect of blocking of the heparin binding site on AT by SR90107A, a synthetic pentasaccharide, on AT-dependent PBMC migration. Coincubation of AT with different concentrations of SR90107A for 20 minutes at room temperature was performed before testing direct lymphocyte (A) and monocyte (B) chemotaxis towards AT. Chemotaxis experiments were performed in modified Boyden chambers. As a control attractant, Rantes was coincubated with SR90107A. Results are given as the mean±s.e.m. of the migration index, which is the ratio of the distance of migration towards AT and the distance towards the medium. Multiple group comparison was performed after Kruskal-Wallis (p=0.0153 for lymphocytes, p=0.0085 for monocytes) followed by Mann-Whitney U-test (*, p<0.05); n=4.