Detection of autoantibody against carbonic anhydrase II in various liver diseases by enzyme-linked immunosorbent assay using appropriate conditions

• Published in: Clinica chimica acta Vol. 342; no. 1; pp. 71 - 81
• Main Authors: Hosoda, Hideo, Okawa-Takatsuji, Masako, Tanaka, Atsushi, Uwatoko, Shu, Aotsuka, Shinichi, Hasimoto, Naoaki, Ozaki, Yukio, Ikeda, Yusei
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.04.2004
• Subjects: Anti-CAII antibodies; Anti-M2 antibody; Autoantibodies - blood; Autoimmune cholangitis; Autoimmune diseases; Carbonic Anhydrase II - blood; Carbonic Anhydrase II - immunology; Cholangitis - diagnosis; Cholangitis - enzymology; Cholangitis - immunology; Chronic Disease; ELISA; Enzyme-Linked Immunosorbent Assay; Hepatitis, Autoimmune - diagnosis; Hepatitis, Autoimmune - enzymology; Hepatitis, Autoimmune - immunology; Hepatitis, Viral, Human - diagnosis; Hepatitis, Viral, Human - enzymology; Hepatitis, Viral, Human - immunology; Humans; Immunoblotting; Immunoglobulin G - blood; Liver Cirrhosis, Biliary - diagnosis; Liver Cirrhosis, Biliary - enzymology; Liver Cirrhosis, Biliary - immunology; Liver Diseases - diagnosis; Liver Diseases - enzymology; Liver Diseases - immunology; Middle Aged; Primary biliary cirrhosis; Sensitivity and Specificity; Anti-CAII antibodies; Primary biliary cirrhosis; Anti-M2 antibody; Autoimmune diseases; Autoimmune cholangitis; ELISA
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/j.cccn.2003.10.015

Background: Immunoglobulin G autoantibody against carbonic anhydrase (CA) II has been detected in the sera of patients with a variety of autoimmune diseases. Antibody against CAII has also been described as a serological marker for distinguishing between cases of autoimmune cholangitis (AIC) and those of primary biliary cirrhosis (PBC). However, the optimal antibody measurement conditions (enzyme-linked immunosorbent assay: ELISA) have not yet been established. Moreover, we also found that a small amount of an IgG-like material exists in purchased CAII reagents, which causes pseudopositive reactions. Methods: The sera of 96 patients with liver disease were examined for the presence of anti-CAII antibody using antigen (CAII) not containing the IgG-like material as the most suitable measurement conditions. Compared with the anti-CAII antibody prevalence of 3.8% found in normal subjects, a significantly higher seroprevalence of the antibody was detected in patients with PBC (31.0%, P<0.02), autoimmune hepatitis (AIH) (50.0%, P<0.01) and chronic viral hepatitis (27.5%, P<0.01). But, in cases of PBC, no significant correlation was noted between the level of anti-CAII antibody and the presence of anti-mitochondrial antibodies (AMA). Conclusions: While CAII may be a target antigen in autoimmune diseases, the anti-CAII antibody is not likely to be a specific marker of AIC. The optimum measurement conditions for the ELISA for anti-CAII antibody would provide us with valuable information to elucidate the underlying immunological abnormalities in liver diseases.