scholarly journals Nucleic Acid Polymers Prevent the Establishment of Duck Hepatitis B Virus InfectionIn Vivo

2013 ◽  
Vol 57 (11) ◽  
pp. 5299-5306 ◽  
Author(s):  
Faseeha Noordeen ◽  
Andrew Vaillant ◽  
Allison R. Jilbert

ABSTRACTNucleic acid polymers (NAPs) are novel, broad-spectrum antiviral compounds that use the sequence-independent properties of phosphorothioate oligonucleotides (PS-ONs) as amphipathic polymers to block amphipathic interactions involved in viral entry. Using the duck hepatitis B virus (DHBV) model of human hepatitis B virus infection, NAPs have been shown to have both entry and postentry antiviral activity against DHBV infectionin vitroin primary duck hepatocytes (PDH). In the current study, various NAPs were assessed for their prophylactic activityin vivoagainst DHBV infection in ducks. The degenerate NAP REP 2006 prevented the development of widespread and persistent DHBV infection in 14-day-old ducks, while the acidic-pH-sensitive NAP REP 2031 had little or no prophylactic effect. REP 2006 displayed significant toxicity in ducks, which was attributed to CpG-mediated proinflammation, while REP 2031 (which has no CpG motifs) displayed no toxicity. A third NAP, REP 2055, which was designed to retain amphipathic activity at acidic pH and contained no CpG motifs, was well tolerated and displayed prophylactic activity against DHBV infection at doses as low as 1 mg/kg of body weight/day. These studies suggest that NAPs can be easily and predictably tailored to retain anti-DHBV activity and to have minimal toxic effectsin vivo. Future studies are planned to establish the therapeutic efficacy of NAPs against persistent DHBV infection.

1989 ◽  
Vol 29 (4) ◽  
pp. 244-248 ◽  
Author(s):  
Hideaki Haritani ◽  
Toshikazu Uchida ◽  
Yasunori Okuda ◽  
Toshio Shikata

2001 ◽  
Vol 34 (1) ◽  
pp. 114-122 ◽  
Author(s):  
Béatrice Seignères ◽  
Stéphanie Aguesse-Germon ◽  
Christian Pichoud ◽  
Isabelle Vuillermoz ◽  
Catherine Jamard ◽  
...  

1996 ◽  
Vol 40 (3) ◽  
pp. 792-794 ◽  
Author(s):  
P Hafkemeyer ◽  
A Keppler-Hafkemeyer ◽  
M A al Haya ◽  
M von Janta-Lipinski ◽  
E Matthes ◽  
...  

The antiviral activity of 2',3'-dideoxy-3'-fluoroguanosine (FdG) or its triphosphate was evaluated in the duck hepatitis B virus (DHBV) system in vitro and in vivo. In primary DHBV-infected hepatocytes FdG results in a dose-dependent inhibition of viral replication with a nearly complete inhibition at a concentration of 1 microM. Also in vivo, FdG treatment of DHBV-infected ducklings reduces DHBV DNA replication by more than 90%. These data demonstrate that FdG is a strong inhibitor of DHBV replication in vitro and in vivo.


1992 ◽  
Vol 18 (2) ◽  
pp. 127-138 ◽  
Author(s):  
Andrew Shead ◽  
Karen Vickery ◽  
Aniko Pajkos ◽  
Robert Medhurst ◽  
John Freiman ◽  
...  

2013 ◽  
Vol 57 (11) ◽  
pp. 5291-5298 ◽  
Author(s):  
Faseeha Noordeen ◽  
Andrew Vaillant ◽  
Allison R. Jilbert

ABSTRACTNucleic acid polymers (NAPs) utilize the sequence-independent properties of phosphorothioate oligonucleotides (PS-ONs) to target protein interactions involved in viral replication. NAPs are broadly active against a diverse range of enveloped viruses that use type I entry mechanisms. The antiviral activity of NAPs against hepatitis B virus (HBV) infection was assessedin vitroin duck hepatitis B virus (DHBV)-infected primary duck hepatocytes (PDH). NAPs efficiently entered PDH in the absence of any transfection agent and displayed antiviral activity at concentrations of 0.01 to 10 μM, measured by their ability to prevent the intracellular accumulation of DHBV surface antigen, which was independent of their nucleotide sequence and was specifically dependent on phosphorothioation. Higher levels of antiviral activity were observed with NAPs 40 nucleotides in length or longer. The fully degenerate NAP (REP 2006) was active during DHBV infection or when added 12 h after infection. In contrast, an acidic-pH-sensitive NAP (REP 2031) that was broadly active against other viruses displayed antiviral activity when present during DHBV infection but no activity when added 12 h after infection, suggesting that NAPs exert their postentry effect in an acidic environment unique to DHBV infection. Both REP 2006 and REP 2031 displayed negligible cytotoxicity in PDH at concentrations of up to 10 μM, as assessed using an XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] cytotoxicity assay. The antiviral activity of NAPs against DHBVin vitrowas strictly dependent on their amphipathic character, suggesting that NAPs interact with amphipathic target(s) that are important for DHBV entry and postentry mechanisms required for infection.


Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3475 ◽  
Author(s):  
Si-Xin Huang ◽  
Jun-Fei Mou ◽  
Qin Luo ◽  
Qing-Hu Mo ◽  
Xian-Li Zhou ◽  
...  

Coumarins are widely present in a variety of plants and have a variety of pharmacological activities. In this study, we isolated a coumarin compound from Microsorium fortunei (Moore) Ching; the compound was identified as esculetin by hydrogen and carbon spectroscopy. Its anti-hepatitis B virus (HBV) activity was investigated in vitro and in vivo. In the human hepatocellular liver carcinoma 2.2.15 cell line (HepG2.2.15) transfected with HBV, esculetin effecting inhibited the expression of the HBV antigens and HBV DNA in vitro. Esculetin inhibited the expression of Hepatitis B virus X (HBx) protein in a dose-dependent manner. In the ducklings infected with duck hepatitis B virus (DHBV), the levels of DHBV DNA, duck hepatitis B surface antigen (DHBsAg), duck hepatitis B e-antigen (DHBeAg), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) decreased significantly after esculetin treatment. Summing up the above, the results suggest that esculetin efficiently inhibits HBV replication both in vitro and in vivo, which provides an opportunity for further development of esculetin as antiviral drug.


1996 ◽  
Vol 40 (5) ◽  
pp. 1180-1185 ◽  
Author(s):  
G Civitico ◽  
T Shaw ◽  
S Locarnini

Safe and effective treatments for chronic hepatitis B virus (HBV) infection have yet to be developed. Both ganciclovir (9-[1,3-dihydroxy-2-propoxymethyl]guanine) and foscarnet (trisodium phosphonoformate hexahydrate) are potent inhibitors of hepadnavirus replication when used individually in vitro and in vivo. However, the clinical usefulness of each drug is reduced by dose-limiting toxicity, especially during long-term monotherapy. Here we demonstrate additive inhibition of duck HBV DNA replication in cultures of primary duck hepatocytes congenitally infected with duck HBV by combinations of ganciclovir and foscarnet at low, clinically achievable concentrations. These results suggest that the effects of ganciclovir and foscarnet against HBV may be additive in vivo.


2000 ◽  
Vol 74 (24) ◽  
pp. 11447-11455 ◽  
Author(s):  
Jianming Hu ◽  
Dana Anselmo

ABSTRACT Reverse transcription in hepatitis B viruses is initiated through a unique protein priming mechanism whereby the viral reverse transcriptase (RT) first assembles into a ribonucleoprotein (RNP) complex with its RNA template and then initiates DNA synthesis de novo using the RT itself as a protein primer. RNP formation and protein priming require the assistance of host cell factors, including the molecular chaperone heat shock protein 90 (Hsp90). To better understand the mechanism of RT activation by Hsp90, we have now mapped the minimal RT sequences of the duck hepatitis B virus that are required for chaperone binding, RNP formation, and protein priming. Furthermore, we have reconstituted in vitro both RNP formation and protein priming using purified RT proteins and host factors. Our results show that (i) Hsp90 recognizes two independent domains of the RT, both of which are necessary for RNP formation and protein priming; (ii) Hsp90 function is required not only to establish, but also to maintain, the RT in a state competent for RNA binding; and (iii) Hsp90 is not required during RT synthesis and can activate the RT posttranslationally. Based on these findings, we propose a model for Hsp90 function whereby the chaperone acts as an active interdomain bridge to bring the two RT domains into a poised but labile conformation competent for RNP formation. It is anticipated that the reconstitution system established here will facilitate the isolation of additional host factors required for RT functions and further elucidation of the mechanisms of RT activation.


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