IFN-CSP Inhibiting Hepatitis B Virus in HepG2.2.15 Cells Involves JAK-STAT Signal Pathway

Abstract

Frequent and high-dose administration of interferon to patients with viral hepatitis results in various side effects. In our previous study, a novel liver-targeting interferon (IFN-CSP) combining Plasmodium region I peptide with IFNα2b was successfully designed and expressed in the Escherichia coli expression systems. This targeting would target the IFNα2b specifically to the liver, thus reducing the adverse events. In the present study, we further investigated the anti-HBV effects and molecular mechanisms of recombinant IFN-CSP in HepG2.2.15 cell line. Hepatitis B surface antigen (HBsAg) and HBe antigen (HBeAg) in the culture supernatants were analyzed by enzyme-linked immunosorbent assay (ELISA). HBV-DNA was measured by real-time quantitative PCR. HBV core protein was assayed by immunofluorescent and western blot analysis. The expressions of signal transducers and transactivator 1 (STAT1), STAT2, IFN regulatory factor 9 (IRF-9), and 2′-5′-oligoadenylate synthetase 1 (OAS1) were investigated by the reverse transcription PCR and western blot analysis. Results indicate IFN-CSP efficiently inhibited HBsAg and HBeAg secretion, HBV-DNA replication, and HBV core protein expression in HepG2.2.15 cells. The anti-HBV mechanisms involve activation of JAK-STAT signaling and increase of the anti-HBV protein OAS expression. IFN-CSP could be a good substitute for IFNα2b for anti-HBV treatment.

Role of Baicalin in Anti-Influenza Virus A as a Potent Inducer of IFN-Gamma

“…As shown in Figure 6(a) , Tyrosine phosphorylation of JAK-1 and JAK-2 was detected within 24 h and sustained for up to 72 h in human PBMC after being treated with 1 mM BA. Transcriptional activation of genes regulated by the JAK-STAT-1 pathway requires phosphorylation of tyrosine residue 701 on STAT-1 by the JAKs [ 28 , 29 ]. The tyrosine phosphorylation of JAK-1 and JAK-2 prompted us to examine the expression and phosphorylation status of STAT-1.…”

Interferon-Stimulated Gene 15 Conjugation Stimulates Hepatitis B Virus Production Independent of Type I Interferon Signaling PathwayIn Vitro

“…However, no significant change of IFN or IFN expression was observed following ISG15 overexpression. Although it has been reported [33] that HBV replication can be significantly suppressed in HepG2.2.15 cells with the 9-day treatment of novel livertargeting interferon 2b (IFN-CSP), our data (unpublished) showed that HBV production in HepG2.2.15 cells is not sensitive to short-period IFN 2b treatment (e.g., 24-72 h treatment), which indicated that the effects of transient ISG15 upregulation (and ISGylation) on HBV production might be independent of type I IFN. Stable transfected HepG2.2.15 cells may be employed to investigate the effect of ISG15 (and ISGylation) on type I IFN signaling pathway in future study.…”

The USP18 cysteine protease promotes HBV production independent of its protease activity

“…It has been reported that HBV DNA in the culture medium was increased by doxycycline treatment [24] or tetherin [25] overexpression while the supernatant HBsAg level was not affected. And Kinoshita W et al [26] found that host factor PRPF31 knockdown suppressed cccDNA production but showed little effect on HBcAg expression. 2) USP18 may affect HBV replication through different ways.…”

“…However, it may be a little bit different in the chronic infection. First of all, JAK-STAT Signaling Pathway has been demonstrated to be involved in regulating HBV replication in HepG2.2.15 cells [10,26] and HepAD38 cells [24,Fig. 5 USP18 upregulation inhibited IFN-induced Jak/STAT signaling pathway.…”