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-α by Macrophages in the inflamed tissue induces the over-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, also under the shear stress of blood flow, causing the leukocytes to "roll" along the internal surface of the blood vessel as temporary interactions are made and broken.