Chemotactic factor that attracts lymphocytes and, slightly, neutrophils, but not monocytes. Inhibitsproliferation of myeloid progenitors in colony formation assays. May be involved in formation and function of themucosal lymphoid tissues by attracting lymphocytes and dendritic cells towards epithelial cells. C-terminal processedforms have been shown to be equally chemotactically active for leukocytes. Possesses antibacterial activity E.coliATCC 25922 and S.aureus ATCC 29213