Human CCL16 (C-C motif chemokine ligand 16), also known as liver-expressed chemokine (LEC) or HCC-4, is a member of the CC chemokine family involved in leukocyte recruitment and regulation of inflammatory responses. CCL16 is constitutively expressed at relatively high levels in the liver and is produced primarily by hepatocytes, with additional expression by monocytes, macrophages, and certain epithelial and stromal cells under inflammatory conditions. It signals mainly through chemokine receptors CCR1, CCR2, and CCR5 to promote chemotaxis and activation of monocytes, lymphocytes, and other immune effector cells. Unlike many chemokines, human CCL16 is detectable in circulation at baseline, contributing to immune surveillance and hepatic immune homeostasis. Expression may increase during systemic inflammation, chronic liver disease, viral hepatitis, metabolic liver disorders, and certain malignancies. In clinical and translational research, human CCL16 is studied as a mediator of mononuclear cell recruitment and as a potential biomarker of hepatic inflammation, chronic inflammatory states, and tumor-associated immune responses.