Figure 1.

Role of syndecans in extravasation. Syndecans bind to inflammatory cytokines and chemokines through GAG chains. This interaction appears to trigger a feedback signaling, which results in an elevated expression of both syndecan and cytokines. The GAG chain mediated binding of syndecan with chemokine and the subsequent shedding of syndecan-chemokine complex results in a stable chemokine gradient. Syndecans mediate a loose interaction between leukocytes and endothelial cells through selectins, which reduces the pace of leukocyte movement and they bigin to roll over the vessel surface. The adhesion between leukocytes and endothelial cells is strengthened by an integrin controlled signaling and other cell adhesion molecules, leading to the arrest of leukocyte rolling. Attached leukocytes begin transmigration directed by a stable chemokine gradient to the site of inflammation.