How does the immune system recognize pathogens?
The immune system recognizes pathogens through cells and molecules that detect common microbial patterns and specific antigen structures.
Biological mechanism and regulation
Innate receptors provide rapid broad responses, while B and T cells recognize more specific antigen features. Antigen-presenting cells connect these arms.
Evidence, applications and limits
Immune tolerance limits attacks on the body. Allergy, autoimmunity and immunodeficiency have different mechanisms, and no single test measures total immune strength. No single molecule or measurement explains the whole system; cell type, timing, environment and feedback must be considered together.
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