title: Porcine interleukin 18: cloning, characterization of the cDNA and expression with the baculovirus system.
abstract: We have isolated and sequenced a cDNA that contains the coding sequence of porcine interleukin 18 (IL-18) and the recombinant protein of porcine IL-18 was expressed using the baculovirus system. The open reading frame (ORF) of the porcine IL-18 cDNA is 579 base pairs (bp) in length and encodes 192 amino acids. The predicted amino acid sequence is 76.7%, 64.7% and 61.6% homologous to the predicted human, murine and rat amino acid sequences, respectively. The porcine precursor and mature IL-18 protein were expressed respectively in Trichoplusia ni -derived (Tn5) cells using the baculovirus Autografha californica nuclear polyhedorosis virus (AcNPV) as a vector. Tn5 cells infected with recombinant virus containing a whole IL-18 protein coding region sequence secreted porcine precursor IL-18 into the culture medium. On the other hand, Tn5 cells infected with recombinant virus containing a mature IL-18 protein coding region sequence expressed several proteins in the cell lysates, but did not secrete mature protein into the culture medium efficiently. Immunoblotting analysis of recombinant protein showed cross-reactivity with anti-human IL-18 polyclonal antibody. The mature form of porcine IL-18 protein induced IFN-gamma production in suboptimal doses of anti-CD3 antibody and concanavalin A- (ConA) stimulated porcine peripheral blood mononuclear cells (PBMC), but the precursor form had little effect.
authors.affiliation: National Institute of Animal Health, Tsukuba, Ibaraki, 305-0856, Japan. ymuneta@niah.affrc.go.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Muneta
authors.forename: Y
authors.initials: Y
authors.lastname: Mori
authors.forename: Y
authors.initials: Y
authors.lastname: Shimoji
authors.forename: Y
authors.initials: Y
authors.lastname: Yokomizo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary; D006801:Humans; D020382:Interleukin-18 / Q000737:chemistry / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D017924:Nucleopolyhedroviruses; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013552:Swine / Q000235:genetics* / Q000276:immunology; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D020382:Interleukin-18; D011994:Recombinant Proteins