Overview
Leukocyte extravasation occurs mainly in post-capillary venules, where haemodynamic shear forces are minimised. This process can be understood in several steps, outlined below as "chemoattraction", "rolling adhesion", "tight adhesion" and "(endothelial) transmigration". It has been demonstrated that leukocyte recruitment is halted whenever any of these steps is suppressed.
White blood cells (Leukocytes) do most of their functions in tissues. Functions include phagocytosis of foreign particles, production of antibodies, secretion of inflammatory response triggers (histamine and heparin), neutralize histamine. In general, leukocytes are involved in the defense of an organism and protect it from disease by promoting or inhibiting inflammatory responses. Leukocytes use the blood as a transport medium to reach the tissues of the body. Studying the question about how leukocytes are capable of getting out of the blood has led to our currently known information on leukocyte extravasation.
Read more about this topic: Leukocyte Extravasation