title: IgA class antibodies to 2-oxo-acid dehydrogenase complex are not predictive markers of histopathological progression in primary biliary cirrhosis.
abstract: Although antimitochondrial antibody (AMA) is the characteristic serological feature of primary biliary cirrhosis (PBC), its pathogenic role remains unclear. In our previous study, we reported a positive correlation between immunoglobulin (Ig) A class anti-2-oxo-acid dehydrogenase complex (2-OADC) and histopathological stage. To determine whether the appearance of IgA class anti-2-OADC by immunoblotting represents an early marker of more aggressive disease or whether it is late finding during the disease course of PBC, we tested not only the entire IgA class but also IgA1, IgA2 and secretory IgA class anti-2-OADC in serial serum samples from 15 patients with PBC. During the median observation period of 51 months, four cases showed histopathological progression (from stage 1 to 2, stage 1 to 3, stage 1 to 4 and stage 2 to 4). There was no statistically significant correlation between the above IgA class anti-2-OADCs and histopathological progression. There was no significant correlation between histopathological stages and IgA2 class anti-2-OADC or secretory IgA class anti-2-OADC by immunoblotting. IgA class anti-2-OADC was more frequent in stages 3-4 than in stages 1-2 (p = 0.0049), but IgA1 class anti-2-OADC was more frequent in stages 1-2 than in stages 3-4 (p = 0.0232). Our present study demonstrated that serum IgA class 2-OADC was not a predictive marker of histopathological progression but was associated with the histopathological stage of PBC. Although the IgA class AMA may have a specific pathogenic role for PBC, the discrepant results between IgA and IgA1 class anti-2-OADC should be further assessed to investigate different functional activities depending on their molecular form.
authors.affiliation: Nagasaki University School of Medicine, Second Department of Internal Medicine, Nagasaki, Japan. omagari@net.nagasaki-u.ac.jp
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Omagari
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Kadokawa
authors.forename: Minoru
authors.initials: M
authors.lastname: Nakamura
authors.forename: Shiho
authors.initials: S
authors.lastname: Akazawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ohba
authors.forename: Ken
authors.initials: K
authors.lastname: Ohnita
authors.forename: Yohei
authors.initials: Y
authors.lastname: Mizuta
authors.forename: Manabu
authors.initials: M
authors.lastname: Daikoku
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yatsuhashi
authors.forename: Hiromi
authors.initials: H
authors.lastname: Ishibashi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kohno
mesh_terms: D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide) / Q000276:immunology*; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood* / Q000145:classification*; D008099:Liver / Q000473:pathology; D008105:Liver Cirrhosis, Biliary / Q000201:enzymology* / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000276:immunology; D009097:Multienzyme Complexes / Q000276:immunology*
chemical_list: D007070:Immunoglobulin A; D009097:Multienzyme Complexes; D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)