title: CD40 ligand/CD40 deficiency.
abstract: CD40 is a surface antigen expressed on B cells. The CD40 ligand (CD40L) is expressed on activated T cells. Interaction between CD40 and CD40L is critical for proliferation and isotype switching in the context of a response to a T-cell-dependent antigen. Patients with X-linked hyper-IgM syndrome (HIGMX-1) in their CD40L gene are unable to switch from IgM to IgG, IgA and IgE. Mice with a disrupted CD40 gene fail to undergo isotype switching to T-cell-dependent antigens but respond normally to T-independent antigens.
authors.affiliation: Division of Immunology, Children's Hospital, Boston, MA 02115, USA.
authors.forename: E
authors.initials: E
authors.lastname: Castigli
authors.forename: R
authors.initials: R
authors.lastname: Fuleihan
authors.forename: N
authors.initials: N
authors.lastname: Ramesh
authors.forename: E
authors.initials: E
authors.lastname: Tsitsikov
authors.forename: A
authors.initials: A
authors.lastname: Tsytsykova
authors.forename: R S
authors.initials: RS
authors.lastname: Geha
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000235:genetics* / Q000502:physiology; D000944:Antigens, Differentiation, B-Lymphocyte / Q000235:genetics* / Q000502:physiology; D000955:Antigens, T-Independent / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D001755:Blastocyst; D019013:CD40 Antigens; D023201:CD40 Ligand; D002678:Chimera; D006801:Humans; D006942:Hypergammaglobulinemia / Q000235:genetics* / Q000276:immunology; D017578:Immunoglobulin Class Switching / Q000235:genetics; D007075:Immunoglobulin M / Q000096:biosynthesis*; D007231:Infant, Newborn / Q000276:immunology*; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation / Q000235:genetics; D008562:Membrane Glycoproteins / Q000172:deficiency* / Q000235:genetics / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D033581:Stem Cell Transplantation; D013601:T-Lymphocytes / Q000276:immunology; D014158:Transcription, Genetic; D014960:X Chromosome
chemical_list: D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D000955:Antigens, T-Independent; D019013:CD40 Antigens; D007075:Immunoglobulin M; D008562:Membrane Glycoproteins; D023201:CD40 Ligand