In Acute inflammation, the mediator for migration and attachment of neutrophils to the endothelium is (LQ)
1. Selectins are a family of cell-surface adhesion molecules of leukocytes and endothelial cells.
2. During an inflammatory response stimuli such as histamine and thrombin cause endothelial cells to mobilize P-selectin from stores inside the cell to the cell surface.
3. In addition, cytokines such as TNF-alpha stimulate the expression of E-selectin and additional P-selectin a few hours later.
4. As the leukocyte rolls along the blood vessel wall, the distal lectin-like domain of the selectin binds to carbohydrate groups presented on proteins (such as PSGL-1) on the leukocyte, which slows the cell and allows it to leave the blood vessel and enter the site of infection/inflammation.