Chemokines and leukocyte trafficking in rheumatoid arthritis Teresa K. Tarrant, Dhavalkumar D. Patel  Pathophysiology  Volume 13, Issue 1, Pages 1-14 (February 2006) DOI: 10.1016/j.pathophys.2005.11.001 Copyright © 2005 Elsevier Ireland Ltd Terms and Conditions

Fig. 1 Schematic depicting the current understanding of leukocyte capture and adhesion that is critical to cellular migration to sites of inflammation. Depicted are circumstances in which (A) selectins, (B) CD44 and (C) CX3CR1 participate in leukocyte capture by endothelial cells. Pathophysiology 2006 13, 1-14DOI: (10.1016/j.pathophys.2005.11.001) Copyright © 2005 Elsevier Ireland Ltd Terms and Conditions

Fig. 2 Signal transduction pathways through chemokine receptors. Classic heterotrimeric G-protein dependent pathways are activated by chemokine agonists and lead to cellular responses via activation of PI3K dependent pathways. Agonist activation also leads to GRK-mediated phosphorylation of the chemokine receptor tail, and binding of b-arrestin. b-arrestin binding not only leads to receptor desensitization to further G-protein mediated signals, but also serves to activate new signaling pathways, possibly leading to different cellular responses. Pathophysiology 2006 13, 1-14DOI: (10.1016/j.pathophys.2005.11.001) Copyright © 2005 Elsevier Ireland Ltd Terms and Conditions