Hepatic allografts from donors positive only for anti-HBs do not transmit HBV infection. Hepatic allografts from anti-HBc-positive donors frequently transmit HBV infection to naive recipients regardless of the donor anti-HBs status, and antiviral prophylaxis may be indicated. Anti-HBs-positive recipients appear resistant to HBV infection after orthotopic liver transplantation with an allograft from an anti-HBc-positive donor. Recipients positive only for anti-HBc infrequently develop HBV infection when transplanted with an allograft from an anti-HBc-positive donor; however, HBV prophylaxis may be justified.

Varicella-zoster virus specifies the formation of several glycoproteins, including the preponderant gp98-gp62 glycoprotein complex in the outer membranes of virus-infected cells. These viral glycoproteins are recognized and precipitated by a previously described monoclonal antibody designated monoclone 3B3. When an immunoblot analysis was performed, only gp98 was reactive with monoclone 3B3 antibody; likewise, titration in the presence of increased concentrations of sodium dodecyl sulfate during antigen-antibody incubations caused selective precipitation of gp98 but not gp62. Further structural analyses of gp98 were performed by using the glycosidases endo-4-N-acetylglucosaminidase H (endoglycosidase H) and neuraminidase and two inhibitors of glycosylation (tunicamycin and monensin). In addition to gp98, antibody 3B3 reacted with several intermediate products, including gp9O, gp88, gp8l, and a nonglycosylated polypeptide, p73. Since gp98 was completely resistant to digestion with endoglycosidase H, it contained only complex carbohydrate moieties; conversely, gp8l contained mainly high-mannose residues. Polypeptide p73 was immunodetected in the presence of tunicamycin and designated as a nascent recipient of N-linked sugars, whereas gp88 was considered to contain 0-linked oligosaccharides because its synthesis was not affected by tunicamycin. The ionophore monensin inhibited production of mature gp98, but other intermediate forms, including gp9O, were detected. Since the latter product was similar in molecular weight to the desialated form of gp98, one effect of monensin treatment of varicella-zoster virus-infected cells was to block the addition of N-acetylneuraminic acid. Monensin also blocked insertion of gp98 into the plasma membrane and, as determined by electron microscopy, inhibited envelopment of the nucleocapsid and its transport within the cytoplasm. On the basis of this study, we reached the following conclusions: (i) the primary antibody 3B3-binding epitope is located on gp98, (ii) gp98 is a mature product of viral glycoprotein processing, (iii) gp98 contains both N-linked and 0-linked oligosaccharide side chains, (iv) gp9O is the desialated penultimate form of gp98, (v) gp88 is an 0-linked intermediate of gp98, (vi) gp8l is the high-mannose intermediate of gp98, and (vii) p73 is the unglycosylated precursor of gp98. two glycosidases (endo-p-N-acetylglycosaminidase H [Endo H] and neuraminidase). Finally, we correlated perturbations 761

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Previous studies have shown that the ZII element in the BZLF1 promoter (P1) is responsive to TPA and anti-immunoglobulin induction. In this report, we have studied the DNA/protein complexes formed when ZII is used as a binding site. Twelve distinct DNA/protein complexes were seen in mobility shift experiments using Akata cell nuclear extracts and radiolabeled ZII. Eleven of these complexes were also formed when either BJAB or Raji cell nuclear extracts were used in the binding reaction. Six DNA/protein complexes were affected by mutations in the core TGACATCA motif of ZII which abolish responsiveness to TPA, anti-immunoglobulin treatment, and HHV6 transactivation. The relative sizes of the proteins in the DNA/protein complexes were determined by UV crosslinking. Four distinct specific binding proteins affected by core mutations in ZII were identified as ATFa, ATF1, ATF2, and c-jun. Overexpression of ATF1 in cotransfection experiments caused transactivation of the wild-type P1 promoter but had no effect on a promoter containing a mutant ZII element. An ATF1 mutant with a deleted DNA binding domain failed to transactivate P1. Overexpression of c-jun, ATFa, or ATF2 had no effect on the wild-type or mutant P1 promoter. Our results suggest that ATF1 interacts with the ZII element and may be involved in Epstein-Barr virus reactivation.