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

Clin Chim Acta. 2004 Apr;342(1-2):71-81. 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.

MeSH terms

  • Autoantibodies / blood*
  • Carbonic Anhydrase II / blood
  • Carbonic Anhydrase II / immunology*
  • Cholangitis / diagnosis
  • Cholangitis / enzymology
  • Cholangitis / immunology
  • Chronic Disease
  • 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
  • Sensitivity and Specificity


  • Autoantibodies
  • Immunoglobulin G
  • Carbonic Anhydrase II