Host innate and adaptive immune system

The host innate and adaptive immune system is a complex, multi-layered defense network designed to protect the body against pathogenic microorganisms, foreign substances, and malignant cells (StatPearls, 2023). The innate immune system serves as the first line of defense, utilizing physical barriers, phagocytic cells like macrophages and neutrophils, and molecular components such as the complement system to provide rapid, non-specific responses (NIH, 2024). In contrast, the adaptive immune system provides a highly specific response characterized by the activation of T and B lymphocytes, which lead to the production of antibodies and the establishment of long-term immunological memory (Janeway's Immunobiology, 2017). Dysregulation of these systems is central to the pathogenesis of numerous conditions, including autoimmune diseases, chronic inflammation, and immunodeficiencies (Nature Reviews Immunology, 2021). Therapeutic intervention often involves modulating specific components of this system, such as using immunosuppressants to treat autoimmunity or checkpoint inhibitors to enhance anti-tumor immunity (PubMed, 2022). Because it encompasses thousands of distinct proteins and cell types, it is considered a biological system rather than a single therapeutic target.

Other names

Immune systemHost immunityInnate immunityAdaptive immunity

Modulation of immune cell activation, cytokine signaling, and antigen-specific responses.