E-selectin

E-selectin, also known as CD62E, is a cell adhesion molecule expressed only on endothelial cells activated by cytokines. Like other selectins, it plays an important part in inflammation.

Ligands
E-selectin recognises and binds to sialylated carbohydrates present on the surface proteins of certain leukocytes. These carbohydrates include members of the Lewis X and Lewis A families found on monocytes, granulocytes, and T-lymphocytes.

Function
During inflammation, E-selectin plays an important part in recruiting leukocytes to the site of injury. The local release of cytokines IL-1 and TNF by damaged cells induces the expression of E-selectin on endothelial cells of nearby blood vessels. Leukocytes in the blood expressing the correct ligand will bind with low affinity to E-selectin, causing the leukocytes to "roll" along the internal surface of the blood vessel as temporary interactions are made and broken.

As the inflammatory response progresses, chemokines released by injured tissue enter the blood vessels and activate the rolling leukocytes, which are now able to tightly bind to the endothelial surface and begin making their way into the tissue.

P-selectin has a similar function, but is expressed on the endothelial cell surface within minutes as it is stored within the cell rather than produced on demand.