Figure 4.

Transiently tethered polymorphonuclear leukocytes dissociate from low-density L-selectin substrates with first order kinetics. Representative data at 1.5 dyn/cm² from the two types of experimental conditions was used for collection of transient tether data, i.e., with a coating concentration of L-selectin at 0.15 μg/ml or with a coating concentration of L-selectin of 0.3 μg/ml and with tethers measured in the presence of 5 μg/ml of fucoidin. Frequency of tethering at 1.5 dyn/cm² was 0.056 and 0.017 events cell⁻¹⋅mm⁻¹ on the L-selectin substrates coated with 0.3 μg/ml and 0.15 μg/ml, respectively.