title: Ultrastructural localization of Pre-S2 polypeptides in the liver tissues of patients with chronic hepatitis B virus infection.
abstract: Pre-S2 polypeptides in the liver tissue were investigated by immunoperoxidase staining in 26 patients with chronic hepatitis B virus (HBV) infection positive for HBeAg. Pre-S2 polypeptides were detected in the liver of 25 patients, in 17 of whom Pre-S2 polypeptides were localized both on the hepatocyte membrane and in the cytoplasm, and in eight of whom only in the cytoplasm. The localization pattern of Pre-S2 polypeptides was not correlated with the histological findings but with the replicative status of HBV. In cases with a high level of DNA-polymerase in the serum or with both nuclear and cytoplasmic expression of HBcAg in the liver, Pre-S2 polypeptides were more frequently expressed both on the hepatocyte membrane and in the cytoplasm (P less than 0.05). Membranous expression of Pre-S2 polypeptides was speculated to be linked to active replication of HBV in the hepatocytes. Under immune electron microscopy, Pre-S2 polypeptides were observed on the plasma membrane, membranes and cisternae of endoplasmic reticulum (ER), or perinuclear space. Moreover, Pre-S2 polypeptides were detected on the tubular structures and the intracisternal particles about 40 nm in diameter considered to represent HBV. These findings suggest that the immunoreactions of Pre-S2 polypeptides in the liver tissue are similar to those of HBsAg, indicating that Pre-S2 polypeptides play an important role in the immunocharacteristics of HBsAg.
authors.affiliation: Third Department of Internal Medicine, Niigata University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Kamimura
authors.forename: H
authors.initials: H
authors.lastname: Asakura
authors.forename: M
authors.initials: M
authors.lastname: Ishikawa
mesh_terms: D006509:Hepatitis B / Q000175:diagnosis*; D006514:Hepatitis B Surface Antigens / Q000032:analysis*; D006515:Hepatitis B virus / Q000302:isolation & purification*; D006801:Humans; D007124:Immunoenzyme Techniques; D008099:Liver / Q000648:ultrastructure*; D008854:Microscopy, Electron; D011498:Protein Precursors / Q000032:analysis*; D014759:Viral Envelope Proteins / Q000032:analysis*; D014779:Virus Replication
chemical_list: D006514:Hepatitis B Surface Antigens; D011498:Protein Precursors; D014759:Viral Envelope Proteins; C050807:presurface protein 2, hepatitis B surface antigen