title: Identification and characterization of functional CD154 (CD40 ligand) in the Pekin duck.
abstract: Binding of CD154, a member of the TNF ligand superfamily, to its receptor CD40 is essential for the development and regulation of adaptive immune responses in mammals. The duck CD154 (DuCD154) encoding gene was isolated from activated splenocytes using RT-PCR. Sequence analysis of the cloned DuCD154 gene revealed an open reading frame of 819 base pairs encoding a 272 amino acid protein. The extracellular domain of DuCD154 was identified and expressed for characterization and generation of antibodies. DuCD154 mRNA was predominantly expressed in spleen, thymus and duodenum. DuCD154 protein generated in cell culture was secreted and formed dimers. DuCD154 markedly enhanced proliferative responses in duck splenocytes when used alone or in conjunction with LPS or PHA. These observations suggest that DuCD154 has functional equivalence with mammalian CD154 and that the central role of CD154 as an immunoregulatory protein had already evolved before the divergence of birds and mammals.
authors.affiliation: Department of Medical Microbiology and Immunology, University of Alberta, 6-22 Heritage Medical Research Centre, Edmonton, Alberta, Canada T6G 2H6.
authors.forename: Karl P
authors.initials: KP
authors.lastname: Fischer
authors.forename: Sheryl L
authors.initials: SL
authors.lastname: Gares
authors.forename: Dakun
authors.initials: D
authors.lastname: Wang
authors.forename: D
authors.initials: D
authors.lastname: Lorne Tyrrell
authors.forename: Klaus S
authors.initials: KS
authors.lastname: Gutfreund
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D023201:CD40 Ligand / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D002478:Cells, Cultured; D004372:Ducks / Q000235:genetics / Q000276:immunology*; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D013154:Spleen / Q000166:cytology / Q000276:immunology
chemical_list: D023201:CD40 Ligand