Complement

Definition

The complement system is a part of the innate immune response consisting of a series of proteins that work together to enhance (complement) the ability of antibodies and phagocytic cells to clear pathogens from an organism. It participates in the opsonization of pathogens, lysis of pathogen cell membranes, and promotion of inflammation.

Related terms

Opsonization:

The process by which pathogens are marked for easier recognition and ingestion by phagocytes.

Phagocytosis:

A form of endocytosis where large particles, such as bacteria, are engulfed by cells, typically immune cells like macrophages.

Inflammation:

A fundamental response mechanism of the body's immune system, characterized by redness, heat, swelling, and pain at sites of infection or injury