Evaluation of oxidized alpha-1-antitrypsin in blood as an oxidative stress marker using anti-oxidative alpha1-AT monoclonal antibody.
BACKGROUND
alpha1-AT is a 52-kDa acute-phase protein and a typical serine proteinase inhibitor, which is present in human serum. In vivo, the inhibitor prevents tissue damage by inactivating proteinases, such as elastase, that are released from activated neutrophils in the presence of inflammation.


METHODS
We obtained a monoclonal antibody against oxidized alpha1-AT(3F4) using chloramine T-oxidized alpha1-AT as the antigen.


RESULTS
This antibody did not react with either the native alpha1-AT or the elastase-alpha1-AT complex. However, it reacted with alpha1-AT oxidized by various oxidants and peroxide lipid. The oxidized alpha1-AT is a polymer with a molecular mass of 100-200 kDa in addition to the 52-kDa protein that corresponds to the native alpha1-AT in sera. In vitro evaluations reveal that fatty acids are involved in the polymerization. Furthermore, the concentrations of oxidized alpha1-AT in the sera of patients with inflammatory and rheumatoid diseases were higher than those in healthy subjects.


CONCLUSIONS
We considered that 3F4 is an effective antibody that can specifically recognize oxidized alpha1-AT, a marker of oxidative stress.
Ueda
Masashi
M
Kyoto Medical Science Laboratory Incorporation, 328 Furukawacho, Hazukashi, Kyoto 612-8486, Fushimi-ku, Japan. ueda@ikagaku.co.jp
Mashiba
Shinichi
S
Uchida
Kazuo
K
D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D000918:Antibody Specificity; D015415:Biomarkers / Q000097:blood*; D002700:Chloramines / Q000378:metabolism; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D051379:Mice; D009504:Neutrophils / Q000276:immunology; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010196:Pancreatic Elastase / Q000378:metabolism; D012680:Sensitivity and Specificity; D014105:Tosyl Compounds / Q000378:metabolism; D000515:alpha 1-Antitrypsin / Q000032:analysis* / Q000276:immunology* / Q000378:metabolism
D000911:Antibodies, Monoclonal; D015415:Biomarkers; D002700:Chloramines; D014105:Tosyl Compounds; D000515:alpha 1-Antitrypsin; C016300:chloramine-T; D010196:Pancreatic Elastase