TNF-alpha, or Tumor Necrosis Factor-alpha, is a protein produced by the immune system that plays a crucial role in inflammation and immune response. It helps regulate various cellular functions, including cell survival, proliferation, and differentiation. Elevated levels of TNF-alpha are often associated with inflammatory diseases, such as rheumatoid arthritis and inflammatory bowel disease. In addition to its role in inflammation, TNF-alpha is involved in the body's defense against infections and tumors. It can induce fever and promote the activation of other immune cells, making it an important target for therapies aimed at reducing excessive inflammation in various medical conditions.