The innate immune system has specific cells whose job is to recognize pathogen-associated molecular patterns. These include the mast cells, macrophage, natural killer cells, dendritic cells, monocyte, neutrophil, basophil, and eosinophil.

When a pathogen enters the body, cells in the blood and lymph detect the specific pathogen-associated molecular patterns (PAMPs) on the pathogen’s surface. The immune system has specific cells with receptors that recognize these PAMPs.

Practice Questions

Key Points

• Pathogens are recognized by a variety of immune cells, such as macrophages and dendritic cells, via pathogen-associated molecular patterns (PAMPs) on the pathogen surface, which interact with complementary pattern-recognition receptors (PRRs) on the immune cells’ surfaces.

• Innate immune system cells include mast cells, macrophage, natural killer cells, dendritic cells, monocyte, neutrophil, basophil, and eosinophil.

Key Terms

immune system: the system that differentiates self from non-self and protects the body from foreign substances and pathogenic organisms by producing an immune response

pathogen: any organism or substance, especially a microorganism, capable of causing diseases, such as bacteria, viruses, protozoa, or fungi

innate: immunity mechanism present since birth

PAMPs: Pathogen-associated molecular patterns are molecules shared by groups of related microbes and bind to pattern-recognition receptors on body cells to induce innate immunity

lymph: fluid that flows through the lymphatic system to return fluid from the tissues to the central circulation.