====== Inflammatory Proteins ====== Inflammatory proteins are molecules produced in response to infection, injury, or cellular stress. They mediate and regulate the inflammatory response, including immune cell recruitment, tissue repair, and resolution. ===== Key Categories ===== ==== Cytokines ==== * **Interleukin-1 (IL-1)**: Promotes fever and activates leukocytes. * **Interleukin-6 (IL-6)**: Induces acute-phase protein production in the liver. * **Tumor Necrosis Factor-alpha (TNF-α)**: Central to systemic inflammation and fever. ==== Chemokines ==== * **CCL2 (MCP-1)**: Recruits monocytes to inflamed tissues. * **CXCL8 (IL-8)**: Attracts neutrophils to the site of infection or injury. ==== Acute-Phase Proteins ==== Produced mainly by the liver in response to IL-6. * **C-Reactive Protein (CRP)**: Binds to pathogens and apoptotic cells; commonly used as a clinical inflammation marker. * **Serum Amyloid A (SAA)**: Elevated in chronic inflammation; associated with secondary amyloidosis. * **Fibrinogen**: Involved in blood clotting and inflammation. ==== Other Mediators ==== * **High-Mobility Group Box 1 (HMGB1)**: Released during necrosis; triggers sterile inflammation. * **Complement components (C3a, C5a)**: Promote opsonization, cell lysis, and chemotaxis. ===== Clinical Relevance ===== * Commonly measured markers: **CRP**, **IL-6**, **TNF-α** * Used in diagnosis or monitoring of: * Infections * Autoimmune diseases (e.g., rheumatoid arthritis) * Cardiovascular risk (e.g., high-sensitivity CRP) * Cancer-associated inflammation * Chronically elevated inflammatory proteins are associated with: * [[atherosclerosis]] * [[neurodegenerative diseases]] (e.g., Alzheimer's disease) * [[cancer]] progression