Figure 11.

Multivalent ligands for L-selectin mimic cell surface glycoproteins. (A) L-selectin expressed on lymphocytes binds to glycoproteins on the endothelium. This interaction slows lymphocyte progression through the vessel and triggers proteolytic release of L-selectin. (B) Multivalent polymers displaying sulfated carbohydrates also bind multiple copies of L-selectin, which leads to receptor clustering and proteolytic shedding. There is a direct relationship between the valency of the polymer, the number of L-selectin proteins bound, and the avidity of the interaction.