Detection of Australia-SH-Antigen in Urine

Abstract

ACCUMULATING evidence suggests an aetiological relationship between Australia (Au/SH)-antigen and serum hepatitis^1–5. So far this antigen has been demonstrated in the serum of diseased and apparently healthy persons only. It has been shown that serum hepatitis can be transmitted orally in humans^6,7, so that the demonstration of this antigen in excretions (urine, faeces, sputum and so on) might be of great epidemiological interest. Because the antigen is likely to be highly diluted in these materials, we concentrated the urine by affinity adsorption chromatography^8,9. About 500 ml. of urine adjusted to pH 7.2 was put through a column of ‘Sepharose 4 B’ (1.0 × 5.0 cm), which was charged with an Au/SH-antigen antiserum (20 mg of protein/ml. of ‘Sepharose’, flow rate, 50 ml./h). After the column had been washed with about 50 ml. of 0.15 M phosphate buffer, pH 7.2, the bound antigen was eluted by using 0.15 M glycine-HCl buffer, pH 1.8. The eluate of about 10 ml. was further concentrated by vacuum ultrafiltration to a final volume of about 0.2 ml., and subjected to immunoelectrophoresis¹⁰. We had checked the sensitivity of the method by diluting 0.1 ml. of serum containing Australia antigen with 500 ml. of water, and confirmed that we could isolate the antigen again. We routinely test sera of patients with suspected liver disease for the presence of Au/SH antigen by immunoelectrophoresis, and the urine of positive cases is further investigated according to the method we have described.