Fig. 4.

Effects of GalNAc-α-O-benzyl treatment on tumor cell–selectin interaction. Expression of sLeA on HT29 and GC5023 as well as sLeX on all sLeX-expressing cells was strongly decreased after treatment with GalNAc-α-O-benzyl (A). Static binding to hESel was reduced by more than 65% for all tested cell lines, while strong effects on mESel binding (>50% reduction) were only observable for HT29 and the two sLeA/X-negative cells lines HOS and SKOV3 (B). P-selectin binding remained unaffected except mPSel binding by HT29 and PaCa5061 cells (B). The strongest effects on dynamic adhesions were seen for sLeA/X-positive cells on hESel and sLeA/X-negative cells on hESel and mESel (C). Effects on adhesion to P-selectins under flow conditions were less striking and differed among the cell lines (D and E). Note the discrepant effects of GalNAc-α-O-benzyl on static vs. dynamic hESel and mESel interaction (sLeX-positive group); in case of mPSel, however, significant reductions of static binding were also visible in the dynamic experiment (HT29 and PaCa5061). See legend to Figure 3 for technical information. This figure is available in black and white in print and in colour at Glycobiology online.