Tumor necrosis factor (TNF) 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 apoptosis (programmed cell death). TNF is primarily secreted by macrophages, a type of white blood cell, in response to infection or injury. In addition to its role in fighting infections, TNF is involved in several diseases, including autoimmune disorders like rheumatoid arthritis and Crohn's disease. Elevated levels of TNF can lead to chronic inflammation, contributing to tissue damage and disease progression. Researchers are exploring TNF inhibitors as potential treatments for these conditions.