TLR4 (Toll-Like Receptor 4): TLR4 is a gene that encodes a protein belonging to the toll-like receptor family, essential for the innate immune system. It recognizes bacterial lipopolysaccharides and plays a key role in triggering immune responses to pathogens. Dysregulation of TLR4 has been associated with various diseases, including sepsis, atherosclerosis, and autoimmune disorders.