AN ENZYME IMMUNE ASSAY FOR SERUM ANTI-ACETALDEHYDE ADDUCT ANTIBODY USING LOW-DENSITY-LIPOPROTEIN ADDUCT AND ITS SIGNIFICANCE IN ALCOHOLIC LIVER-INJURY

An acetaldehyde (AcH) adduct was prepared using rabbit low-density lip oprotein as carder proteins. An antibody against this adduct was raise d in Watanabe heritable hyperlipidemic rabbits and crossreacted with h uman low-density lipoprotein and bovine serum albumin adducts. Using t his antibody, serum anti-AcH-adduct antibody levels were measured by a direct ELISA method in 56 Japanese adults (healthy adults and patient s with nonalcoholic gastrointestinal diseases, alcoholic liver injury, or alcoholic pancreatitis). The antibody level (mean +/- SD) was 22 /- 10 mu g/ml in healthy adults, 22 +/- 11 mu g/ml in nonalcoholic gas trointestinal diseases, and 16 +/- 13 mu g/ml in alcoholic pancreatiti s. These antibody levels tended to increase with the progression of al coholic liver injury, starting from fatty liver via hepatitis to cirrh osis, 29 +/- 24 mu g/ml in fatty liver, 35 +/- 29 mu g/ml in alcoholic hepatitis, and 46 +/- 54 mu g/ml in alcoholic cirrhosis. The antibody level in patients taking 100 g or more of ethanol per day tended to b e higher, compared with those in people taking less ethanol. A follow- up observation revealed that alcohol abstinence after hospitalization raised serum anti-AcH-adduct antibody level in some patients and kept it constantly low in other patients. The immunohistochemical study usi ng the anti-AcH-adduct antibody revealed the presence of adduct-like s ubstance in hepatocytes of liver biopsy specimens obtained from patien ts with alcoholic liver disease. The results indicate that the anti-Ac H-adduct antibody may be associated with the progress of alcoholic liv er diseases.