title: A new isoform of interleukin-32 suppresses IL-8 mRNA expression in the intestinal epithelial cell line HT-29.
abstract: Interleukin (IL)-32 plays a role in the pathophysiology of inflammatory bowel disease (IBD). We isolated a new isoform of the IL-32 transcript in the process of cloning the full-length IL-32 gene from human colonic subepithelial myofibroblasts (SEMFs). The expression of mRNA in the samples was assessed by RT-PCR and real-time PCR analyses. The PCR products from the IL-32 genes were ligated into the expression vector pIRESneo2. The new isoform of the IL-32 transcript (336 nucleotides) completely lacked exon 4 of the IL-32γ gene, and was 60 bp shorter than IL-32α. TNF-α induced the mRNA expression of the new IL-32 isoform in a dose- and time-dependent manner. Stable transfection of this new isoform significantly decreased TNF-α-induced IL-8 mRNA expression in HT-29 cells, but the expression of the IL-32α gene had no effect. The mRNA expression of this new isoform was significantly elevated in the inflamed mucosa of IBD patients. A new isoform of the IL-32 transcript may play an anti-inflammatory role in the inflamed mucosa of IBD.
authors.affiliation: Department of Medicine, Graduate School of Medicine, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, Shiga 520-2192, Japan.
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Imaeda
authors.forename: Akira
authors.initials: A
authors.lastname: Andoh
authors.forename: Tomoki
authors.initials: T
authors.lastname: Aomatsu
authors.forename: Rie
authors.initials: R
authors.lastname: Osaki
authors.forename: Shigeki
authors.initials: S
authors.lastname: Bamba
authors.forename: Osamu
authors.initials: O
authors.lastname: Inatomi
authors.forename: Tomoharu
authors.initials: T
authors.lastname: Shimizu
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Fujiyama
mesh_terms: D001483:Base Sequence; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D019073:HT29 Cells; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000235:genetics / Q000473:pathology; D016209:Interleukin-8 / Q000235:genetics* / Q000378:metabolism; D007378:Interleukins / Q000235:genetics / Q000378:metabolism*; D007422:Intestines / Q000473:pathology*; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: C508606:CXCL8 protein, human; C496971:IL32 protein, human; D016209:Interleukin-8; D007378:Interleukins; D020033:Protein Isoforms; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha