title: Mutations of CD40 ligand in two patients with hyper-IgM syndrome.
abstract: Two patients with the X-linked form of the hyper-IgM syndrome have been studied. Both patients present: 1. Mutations in the CD40L gene (a nonsense point mutation that introduces a termination codon at the extracellular domain of the protein, and a deletion that eliminates exon 4 as consequence of an abnormal splicing). 2. Lack of CD40L expression on the lymphocyte surface after stimulation with ionomycin and PMA. 3. Altered lymphocytic proliferation in response to anti-CD3. 4. Hyper IgM, low IgG and IgA levels and neutropenia. One of the patients shows, in addition, low Natural Killer cell numbers and severe herpetic infections, which distinguishes this case from the common hyper-IgM syndrome phenotype. Finally, a hyper-IgM stable phenotype has been immortalized by Herpes virus Saimiri for the first time.
authors.affiliation: Departmento de Pediatría, Obstetricia y Ginecología, Facultad de Medicina, Valencia, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: García-Pérez
authors.forename: Estela
authors.initials: E
authors.lastname: Paz-Artal
authors.forename: Alfredo
authors.initials: A
authors.lastname: Corell
authors.forename: Angel
authors.initials: A
authors.lastname: Moreno
authors.forename: Alberto
authors.initials: A
authors.lastname: López-Goyanes
authors.forename: Francisco
authors.initials: F
authors.lastname: García-Martín
authors.forename: Rosario
authors.initials: R
authors.lastname: Vázquez
authors.forename: Aranzazu
authors.initials: A
authors.lastname: Pacho
authors.forename: Eva
authors.initials: E
authors.lastname: Romo
authors.forename: Luis M
authors.initials: LM
authors.lastname: Allende
mesh_terms: D000293:Adolescent; D000917:Antibody Formation; D001483:Base Sequence; D023201:CD40 Ligand / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D041321:Chromosomes, Human, X; D016207:Cytokines / Q000097:blood; D008040:Genetic Linkage; D006801:Humans; D006942:Hypergammaglobulinemia / Q000235:genetics*; D007073:Immunoglobulin E / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood*; D007223:Infant; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype
chemical_list: D016207:Cytokines; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D023201:CD40 Ligand; D007073:Immunoglobulin E