Journal of Biochemistry Advance Access originally published online on February 13, 2007
Journal of Biochemistry 2007 141(3):429-441; doi:10.1093/jb/mvm047
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
© 2007 The Japanese Biochemical Society.
Identification of an Inflammation-inducible Serum Protein Recognized by Anti-disialic Acid Antibodies as Carbonic Anhydrase II
1Laboratory of Animal Cell Function, Bioscience and Biotechnology Center; 2Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences; and 3Institute for Advanced Research, Nagoya University, Nagoya 464-8601, Japan
*To whom correspondence should be addressed. Tel: +81-52-789-4297, Fax: +81-52-789-5228, E-mail: chi{at}agr.nagoya-u.ac.jp
Received January 17, 2007; Accepted January 20, 2007
| Abstract |
|---|
Acute-phase proteins are an important marker of inflammation and sometimes have a role in the general defense response towards tissue injury. In the present study, we identified a 32-kDa protein that was immunoreactive with monoclonal antibody 2-4B (mAb.2-4B), which is specific to di/oligoNeu5Gc structures, and that behaved as an acute-phase protein following stimulation with either turpentine oil or lipopolysaccharides. The 32-kDa protein was identified as carbonic anhydrase II (CA-II), based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses of the purified protein. Mouse and human CA-II was immunoreactive and immunoprecipitated with mAb.2-4B, but contained no sialic acid. In addition to mAb.2-4B, the mAb. S2-566 an antibody specific for diNeu5Ac-containing glycans, recognized the CA-II, whereas an anti-oligo/polysialic acid antibody did not. These results indicate that a part of the CA-II protein structure mimics the disialic acid structure recognized by the monoclonal antibodies. This is the first report that CA-II circulates in the serum following inflammation.
Key Words: acute-phase protein, carbonic anhydrase II, disialic acid, inflammation, serum
Abbreviations: diSia, disialic acid; DMB, 1,2-diamino-4,5-methylenedioxybenzene; PBS, phosphate-buffered saline; PBS-T, PBS containing 0.05% Tween 20; PVDF, polyvinylidene difluoride; CA-II, carbonic anhydrase II