Selectin Binding to a Glycoprotein Ligand

Selectins are transmembrane proteins with membrane-distal Ca +-dependent lectin domains. This family of cell adhesion molecules is involved in the tethering and rolling of leukocytes on the blood vessel endothelium. Nicholson and colleagues [10] published the analysis of leukocyte selectin, CD62L, binding to the mucin-like glycoprotein, Gly-CAM-1. 

The binding response dropped with a half time of 0.07 sec after switching to buffer, corresponding to a dissociation rate constant of fcdiss 10 sec . But, since it 

The data supported the hypothesis that the highly dynamic cell adhesion process is based on the low affinity and fast kinetics of selectin interaction. GlyCAM-1 was shown to bind multivalently to immobilized CD62L at concentrations just above its mean serum level, indicating a physiological role by interacting with CD62L embedded in leukocyte membranes. 

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