title: 4-Hydroxynonenal modifies IgA in rat intestine after lipopolysaccharide injection.
abstract: The lipid peroxide 4-hydroxynonenal (HNE) was measured in rat intestinal mucosa after lipopolysaccharide (LPS) injection (0.5 mg/kg, ip) by a highly sensitive time-resolved fluoroimmunoassay. HNE was increased, with a small peak at 20 min followed by a sustained elevation at 2-4 h, after injection of LPS. Immunohistochemistry demonstrated enhanced labeling with anti-IgA and anti-HNE antibodies in the plasma cells followed by diffusion of the labeled materials into the submucosal tissue after LPS injection. Immunoprecipitation with anti-IgA antibody and Western blotting with anti-HNE antibody showed that IgA is modified with HNE after LPS injection. The HNE (5 microM-5 mM) modification in vitro reduced the bactericidal activity of IgA and anti-Escherichia coli serum. The HNE modification in vitro also promoted polymerization of IgA as shown by nondenaturing gel electrophoresis. This is the first demonstration of the modification of IgA with HNE in an in vivo model of intestinal inflammation as well as in vitro effects of HNE on bactericidal activity and polymerization of IgA. These findings will help in understanding the involvement of oxidative stress in the IgA-mediated immune response exerted by plasma cells in early intestinal inflammation.
authors.affiliation: Department of Forensic Medicine, Juntendo University School of Medicine, Hongo 2-1-1, Tokyo, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Kimura
authors.forename: Masahiro
authors.initials: M
authors.lastname: Mukaida
authors.forename: Kyoko
authors.initials: K
authors.lastname: Kuwabara
authors.forename: Teruyo
authors.initials: T
authors.lastname: Ito
authors.forename: Kimikazu
authors.initials: K
authors.lastname: Hashino
authors.forename: Koji
authors.initials: K
authors.lastname: Uchida
authors.forename: Kazuko
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Yoshida
mesh_terms: D000447:Aldehydes / Q000494:pharmacology*; D000818:Animals; D004926:Escherichia coli / Q000276:immunology; D006801:Humans; D018928:Immunity, Mucosal / Q000187:drug effects; D007070:Immunoglobulin A / Q000187:drug effects / Q000378:metabolism*; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000187:drug effects / Q000276:immunology*; D008070:Lipopolysaccharides / Q000633:toxicity*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000447:Aldehydes; D007070:Immunoglobulin A; D008070:Lipopolysaccharides; C027576:4-hydroxy-2-nonenal