title: Characterization of autoantibodies to ferritin in canine serum.
abstract: Ferritin-binding proteins circulating in mammalian blood are thought to be involved in the clearance of ferritin. The present study characterizes canine serum autoantibodies (IgM and IgA) that react with ferritin. Canine IgM and IgA bound to bovine spleen ferritin as well as canine liver ferritin. To examine the specificity of canine IgM and IgA to ferritin H and L subunits, we used canine heart ferritin and canine liver ferritin with H/L subunit ratios of 3.69 and 0.43, respectively. Canine IgM and IgA recognized both of the H- and L-subunit-rich isoferritins, showing that their binding activities to ferritin depend on the H-subunit content. Recombinant bovine H-chain ferritin homopolymer expressed in a baculovirus expression system bound more with IgM and IgA than the recombinant L-chain homopolymer expressed under the same conditions. These results suggest that canine IgM and IgA recognize H-subunit-rich isoferritins, and that H-subunit-rich isoferritins are cleared from the circulation more rapidly than L-subunit-rich isoferritins.
authors.affiliation: Laboratory of Biochemistry, School of Veterinary Medicine and Animal Sciences, Kitasato University, Aomori, Japan. orino@vmas.kitasato-u.ac.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Orino
authors.forename: Misaki
authors.initials: M
authors.lastname: Higa
authors.forename: Mika
authors.initials: M
authors.lastname: Fujikawa
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Takehara
authors.forename: Shozo
authors.initials: S
authors.lastname: Okano
authors.forename: Shinji
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Watanabe
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology*; D002417:Cattle; D004285:Dogs / Q000097:blood / Q000276:immunology*; D005293:Ferritins / Q000097:blood / Q000737:chemistry / Q000276:immunology*; D007070:Immunoglobulin A / Q000097:blood / Q000276:immunology; D007075:Immunoglobulin M / Q000097:blood / Q000276:immunology; D008099:Liver / Q000737:chemistry; D009206:Myocardium / Q000737:chemistry; D021122:Protein Subunits
chemical_list: D001323:Autoantibodies; D007070:Immunoglobulin A; D007075:Immunoglobulin M; D021122:Protein Subunits; D005293:Ferritins