Rho kinase is required for CCR7-mediated polarization and chemotaxis of T lymphocytes.

We studied the role of Rho kinase and extracellular signal-regulated kinase (ERK)-2 in the polarization and migration of T lymphocytes in response to the CCR7 ligands EBI1 ligand chemokine (ELC; CCL19) and secondary lymphoid-tissue chemokine (SLC; CCL21). Both Rho kinase protein isoforms are expressed in T lymphocytes. Inhibition of the Rho kinases with Y-27632 strongly inhibited SLC- and ELC-induced polarized morphology and chemotaxis of T lymphocytes. Although the chemokines induced ERK-2 activation, the blockade of this signaling pathway showed no effect on polarization and migration. This study indicates an important role of Rho kinase in CCR7-mediated polarization and migration of T lymphocytes, whereas ERK-2 is not involved in these processes.