selektiinejä

Selektiinijä, often referred to as selectins, are a family of cell adhesion molecules that play a crucial role in the immune response and hemostasis. They are transmembrane glycoproteins primarily found on the surface of leukocytes, endothelial cells, and platelets. Selectins mediate the initial tethering and rolling of leukocytes along the vascular endothelium, a critical step in their migration from the bloodstream to inflammatory sites or sites of injury.

There are three main types of selectins: L-selectin, E-selectin, and P-selectin. L-selectin is expressed on most leukocytes and mediates their rolling on endothelial cells. E-selectin is expressed on activated endothelial cells and binds to leukocytes. P-selectin is stored in the granules of platelets and endothelial cells and is rapidly mobilized to the cell surface upon activation, playing a role in platelet aggregation and leukocyte adhesion.

The interaction between selectins and their ligands, which are often carbohydrate structures, is characterized by its transient nature, allowing for the characteristic rolling motion. This rolling allows leukocytes to sense the inflammatory environment and respond appropriately by firming up their adhesion and migrating into tissues. Dysregulation of selectin function can contribute to various inflammatory diseases, making them a target for therapeutic interventions.