Innate Immunity

Innate immunity is the body's first line of defense against pathogens, providing an immediate, non-specific response to foreign invaders. It includes physical and chemical barriers like the skin and mucous membranes, as well as immune cells like phagocytes that can recognize and destroy common microbial components. Innate immunity does not require prior exposure to a pathogen and lacks immunological memory, in contrast to the adaptive immune system. Key components of innate immunity include pattern recognition receptors that detect pathogen-associated molecular patterns, the complement system, and inflammatory responses mediated by cytokines and other signaling molecules.