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What causes inflammation in damaged body tissues?

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Pathways of complement activation — inflammation The main function of complement proteins is to aid in the destruction of pathogens by piercing their outer membranes (cell lysis) or by making them more attractive to phagocytic cells such as macrophages (a process known as opsonization). Some complement components also promote inflammation by stimulating cells to release histamine and by attracting phagocytic cells to the site of infection.

Inflammation is a protective physiological response triggered by damage to living tissues, with the primary goal of removing damaged components to facilitate healing. While injury initiates this process, the actual vascular and cellular changes are driven by chemical mediators released from blood plasma, white blood cells, platelets, mast cells, and damaged tissue cells.12

Key factors that stimulate this response include:
* Physical and Chemical Agents: Trauma, burns, radiation, frostbite, and corrosive chemicals.3
* Infectious Agents: Bacteria (via endotoxins) and viruses.3
* Biological Triggers: Tissue death due to lack of oxygen or nutrients, and inappropriate immunological responses.3

Once triggered, mediators like histamine, prostaglandins, cytokines, and complement proteins cause blood vessels to dilate and increase their permeability. This allows fluids, proteins, and white blood cells to migrate to the site of injury, resulting in the characteristic redness, heat, and swelling associated with inflammation.21