title: Expression of interleukin-18 by porcine airway and intestinal epithelium.
abstract: In this study, we investigated the expression of interleukin-18 (IL-18) in porcine airway and intestinal epithelium. We found constitutive protein expression of precursor IL-18 in primary culture of porcine airway epithelium. Immunohistochemical staining revealed that porcine IL-18 was localized in the porcine airway epithelium and that it was significantly upregulated with experimental endotoxemia induced by Escherichia coli lipopolysaccharide (LPS) inoculation. We also confirmed by immunohistochemical staining that IL-18 was expressed in porcine intestinal epithelial cells. Moreover, the concentration of IL-18 in intestinal cell lysates of 1-day-old piglets was about 3-fold and 6-fold less than that in those of 1-month-old and 6-month-old piglets, respectively. Exogenous IL-18 was able to induce interferon-gamma (IFN-gamma) in the peripheral blood of 1-day-old piglets, whereas concanavalin A (ConA) was not able to induce IFN-gamma in the same condition. These results suggest that mucosal epithelial cells are among the major sources of IL-18 in pig and that IL-18 may be useful as a therapeutic agent for the enhancement of immune responses and as a vaccine adjuvant, especially in neonatal piglets.
authors.affiliation: National Institute of Animal Health, Tsukuba, Ibaraki 305-0856, Japan. ymuneta@affrc.go.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Muneta
authors.forename: Noriko
authors.initials: N
authors.lastname: Goji
authors.forename: Noriko M
authors.initials: NM
authors.lastname: Tsuji
authors.forename: Osamu
authors.initials: O
authors.lastname: Mikami
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Shimoji
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Nakajima
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Yokomizo
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Mori
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000378:metabolism; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics; D020382:Interleukin-18 / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics / Q000494:pharmacology; D007413:Intestinal Mucosa / Q000378:metabolism*; D007421:Intestine, Small / Q000378:metabolism; D016676:Macrophages, Alveolar / Q000378:metabolism; D008297:Male; D009092:Mucous Membrane / Q000378:metabolism; D013552:Swine / Q000378:metabolism*; D014132:Trachea / Q000378:metabolism*
chemical_list: D020382:Interleukin-18; D007371:Interferon-gamma