IL-16 (Interleukin-16) is a chemotactic cytokine that stimulates a migratory response in CD4+ lymphocytes,Mouse,onocytes and eosinophils through binding to the CD4 receptor. IL-16 induces human T-lymphocyte e, Xenopus/Amphibian,pression of interleukin 2 receptor and upregurates major histocompatibility comple, Xenopus/Amphibian, ?molecules on resting human T lymphocyte. It is able to render CD4+ T cells unresponsive to TCR/CD3 stimuli. Moreover, IL-16 inhibits the replication of T cell and monocyte tropic HIV strains in vitro.