title: B lymphocyte-derived IL-16 attracts dendritic cells and Th cells.
abstract: Interaction of B lymphocytes with Th cells is a fundamental step in the establishment of humoral immunity, and recent evidence suggests that direct interaction between B lymphocytes and dendritic cells (DCs) is also an important prerequisite. Factors involved in the selective recruitment of Th cells and DCs by B lymphocytes are insufficiently defined. We set out to delineate the role of IL-16, the soluble ligand of CD4, which is expressed on Th cells and DCs. B lymphocytes express IL-16 mRNA and synthesize bioactive IL-16 protein, and IL-16 is expressed in lymph node follicles in situ. B lymphocyte supernatant efficiently induces migration of CD4+ Th cells, monocyte-derived DCs, and circulating blood DCs in nitrocellulose filter-based assays. Neutralization of IL-16 bioactivity strongly inhibits this migratory response, suggesting that IL-16 might be a major chemotactic factor derived from B cells. The present data further support the idea that IL-16 might have a role in the initiation of cellular as well as humoral immunity by mediating the cellular cross-talk among T lymphocytes, B cells, and DCs, leading to recruitment of these cell types at common anatomical sites.
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Medicine, University Hospital Innsbruck, Innsbruck, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Kaser
authors.forename: S
authors.initials: S
authors.lastname: Dunzendorfer
authors.forename: F A
authors.initials: FA
authors.lastname: Offner
authors.forename: O
authors.initials: O
authors.lastname: Ludwiczek
authors.forename: B
authors.initials: B
authors.lastname: Enrich
authors.forename: R O
authors.initials: RO
authors.lastname: Koch
authors.forename: W W
authors.initials: WW
authors.lastname: Cruikshank
authors.forename: C J
authors.initials: CJ
authors.lastname: Wiedermann
authors.forename: H
authors.initials: H
authors.lastname: Tilg
mesh_terms: D001402:B-Lymphocytes / Q000378:metabolism / Q000502:physiology*; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology; D002474:Cell-Free System / Q000276:immunology / Q000502:physiology; D002478:Cells, Cultured; D002630:Chemotactic Factors / Q000502:physiology*; D002634:Chemotaxis, Leukocyte; D003713:Dendritic Cells / Q000502:physiology*; D006801:Humans; D019410:Interleukin-16 / Q000096:biosynthesis / Q000502:physiology*; D014066:Palatine Tonsil / Q000166:cytology / Q000502:physiology; D006377:T-Lymphocytes, Helper-Inducer / Q000502:physiology*
chemical_list: D002630:Chemotactic Factors; D019410:Interleukin-16