title: CD40L: a multi-functional ligand.
abstract: B cells can be stimulated to proliferate and differentiate in response to cell-contact dependent signals provided by activated, but not resting, T cells. In the human system, antibodies specific for the surface antigen CD40 induce similar B cell responses. The cloning of a ligand for CD40, and the generation of reagents which can block the interaction of this ligand with its receptor, have demonstrated that the major component of the contact-dependent signal leading to B cell activation is CD40 ligand. Studies of individuals lacking functional CD40 ligand have indicated that signaling through CD40 is essential for immunoglobulin (Ig) heavy chain switching and the production of all isotypes other than IgM. In addition to its activities on B cells, CD40 ligand is stimulatory for cells of monocyte and T lineages suggesting a pleiotropic role for CD40 ligand in vivo.
authors.affiliation: Department of Cellular Immunology, Immunex Research and Development Corporation, Seattle, WA 98101.
authors.forename: R J
authors.initials: RJ
authors.lastname: Armitage
authors.forename: C R
authors.initials: CR
authors.lastname: Maliszewski
authors.forename: M R
authors.initials: MR
authors.lastname: Alderson
authors.forename: K H
authors.initials: KH
authors.lastname: Grabstein
authors.forename: M K
authors.initials: MK
authors.lastname: Spriggs
authors.forename: W C
authors.initials: WC
authors.lastname: Fanslow
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000502:physiology*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000502:physiology*; D001402:B-Lymphocytes / Q000276:immunology; D019013:CD40 Antigens; D023201:CD40 Ligand; D002450:Cell Communication / Q000502:physiology*; D006801:Humans; D007154:Immune System Diseases / Q000276:immunology; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D019013:CD40 Antigens; D008562:Membrane Glycoproteins; D023201:CD40 Ligand