Methods for the Recognition of GAG-Bound Chemokines

Chemokines play a pivotal role in the multistep cascade of cellular recruitment, where they provide the directional signal. They activate cells through a high-affinity interaction with their receptors, members of the large family of heptahelical G protein-coupled receptors. In order to provide the directional signal, they bind to cell surface proteoglycans through a low-affinity interaction with the glycosaminoglycan (GAG) moiety. While several methods have been described to measure the chemokine-GAG interaction, this chapter describes methods to identify whether anti-chemokine antibodies or chemokine-binding proteins recognize the GAG-bound chemokine.