Answer: Leukocytes recruitment is a phenomena which causes the leukocytes to travel to the site of inflammation.
Step-by-step explanation:
When there is an inlfammation anywhere in the body due to any cell injury,necrosis,infection or a foreign body, mediators are released from the site of inflammation which activates the leukocytes. Leukocytes are the white blood cells i.e neutrophils and macrophages which fight against the inflammatory agents.
Mediators released from the site if inflammation as in Cytokines and TNF (tissue necrosis factor) activate the integrins and endothelial adhesion molecules which causes the attachment and rolling of the leukocytes on the endothelium. Chemokines are the substances which attract the leukocytes to the site of inflammation. Later these chemokines causes the leukocytes to extravasate out of the vessels to the site of inflammation and fight the inflammatory substances.