Inflammation: Occurs when injured cells release chemokines. This attracts neutrophils and also acts on mast cells, causing them to release histamine. Mast cells alert the body after detecting foreign material, releasing chemical signals and blood is rushed to the area, bringing white blood cells. Dilation of blood vessels and infiltration of inflammatory cells at the site of infection causes heat, pain, redness, swelling, and the acute loss of function. When tissues are damaged, they release histamines which increase permeability of proximal blood vessels and allow WBCs to travel more easily to the site. The purpose of inflammation is to eliminate the cause of injury (the pathogen), clear out necrotic cells from the area of infection, and initiate tissue repair by stimulating the flow of blood to the area. By heating the area, pathogens are subjected to higher temperatures which may deactivate them due to their enzymes, stopping infection. Increased temperature enhances activity of white blood cells.