HBsAg in urine: a new approach for the detection of urinary antigens.
In order to define the optimal conditions for detection of microbial antigens in urine, urinary HBsAg excreted during hepatitis B was chosen as a model. Using commercial kits, which mainly involve anti-discontinuous epitopes, we found urinary HBsAg in only 50% of patients with HBsAg in their sera. In contrast, with an inhibition method involving a monoclonal antibody recognizing a continuous epitope, urinary HBsAg was found in 100% of these patients. Structural analysis of HBsAg showed that urinary HBsAg is denatured; it can escape detection by commercial kits well fitted for detection of native serum HBsAg. General implications for the revelation of urinary microbial antigens are discussed.
Badur
S
S
Service de Microbiologie et d'Immunologie, Hôpital Antoine Béclère, Clamart, France.
Grangeot-Keros
L
L
Pillot
J
J
D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D000939:Epitopes; D006509:Hepatitis B / Q000175:diagnosis*; D006510:Hepatitis B Antibodies / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000097:blood / Q000737:chemistry / Q000652:urine*; D006513:Hepatitis B e Antigens / Q000097:blood; D006801:Humans; D007124:Immunoenzyme Techniques; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry / Q000276:immunology / Q000652:urine; D011489:Protein Denaturation
D000911:Antibodies, Monoclonal; D000939:Epitopes; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D010446:Peptide Fragments