Interleukin-6 (IL-6) is a cytokine that plays a pivotal role in immune response, inflammation, and hematopoiesis. It is produced by various cell types, including macrophages, T cells, and endothelial cells, in response to infections, injuries, or inflammatory stimuli. IL-6 is involved in the regulation of acute-phase proteins, which help the body respond to stress or infection. It is also a key player in the pathogenesis of various diseases, such as autoimmune disorders, chronic inflammatory conditions, and certain cancers. Elevated levels of IL-6 have been associated with poor prognosis in conditions like sepsis, rheumatoid arthritis, and COVID-19, making it an important biomarker for disease monitoring and potential therapeutic targeting