title: Dane particles and associated DNA-polymerase activity in saliva of chronic hepatitis B carriers.
abstract: To investigate furhter the problem of salivary transmission of type B hepatitis, salivas free of blood contamination from three HBsAg-positive carriers with chronic active hepatitis were examined by CsCl equilibrium density gradients and electron microscopy (EM). In the CsCl gradient HBsAg of whole salivas distributed in a band centered at 1.19gm/cm3 with a clearly defined shoulder at 1.24 gm/cm3; the HBsAg was found mainly in the mucous component. On EM examination, fractions from the 1.19 gm/cm3 peak contained spherical HBsAg particles of 22 +/- 3 nm diameter, whereas in the 1.24 gm/cm3 shoulder Dane particles 43 nm in diameter with 28 nm cores were found. Specific hepatitis B virus associated DNA-polymerase activity also was found in the 1.24 gm/cm3 shoulder where the Dane particles occurred and was absent from the saliva of healthy controls. When salivas were incubated for three hours at 37 degrees C the total amount of HBsAg diminished and the 1.24 gm/cm3 shoulder disappeared, probably as a result of endogenous degradation of the Dane particles and the free HBsAg. These findings clearly indicate that the hepatitis B viral particle is present in the saliva of chronic HBsAg carriers with active disease and further confirm that saliva is an important vehicle of infection.
mesh_terms: D000293:Adolescent; D000328:Adult; D002353:Carrier State / Q000201:enzymology / Q000276:immunology*; D002648:Child; D004259:DNA-Directed DNA Polymerase / Q000032:analysis*; D005260:Female; D006509:Hepatitis B / Q000201:enzymology / Q000276:immunology* / Q000635:transmission; D006511:Hepatitis B Antigens / Q000032:analysis*; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000201:enzymology; D006801:Humans; D008297:Male; D011863:Radioimmunoassay; D012463:Saliva / Q000201:enzymology / Q000276:immunology*
chemical_list: D006511:Hepatitis B Antigens; D006514:Hepatitis B Surface Antigens; D004259:DNA-Directed DNA Polymerase