Superinfection of hepatitis A virus in hepatocytes infected with hepatitis B virus

Abstract

Hepatitis A virus (HAV) infection is a major cause of acute hepatitis including acute liver failure. Hepatitis B infection (HBV) occurs worldwide, with the highest rates in Asian and African countries, and there are several reports that HAV infection may have a more severe clinical course in patients with chronic HBV infection. We previously demonstrated that Japanese miso extracts have inhibitory effects on HAV replication. In the present study, we examined the replication of HAV and HBV in a hepatocyte superinfection model and the inhibitory effects of Japanese miso extracts on both viruses. According to the results, HAV infection inhibited HBV replication in superinfected hepatocytes, and Japanese rice-koji miso extracts had inhibitory effects on HAV replication. Our findings provide useful information for clinicians in managing HAV infection in patients with chronic HBV infection.

Keywords: HAV; HBV; dual infection; miso extracts; rice koji.

Figure 1

HBV replication is inhibited in HAV-infected HepG2.2.15 cells compared to HepG2.2.15 cells. (A) HAV RNA levels in HepG2 and HepG2.2.15 cells at 96 h post infection with the HAV HA11-1299 genotype IIIA strain. (B) HBV DNA levels in HepG2.2.15 cells infected with or without the HAV HA11-1299 genotype IIIA strain at 96 h post infection. HAV RNA and HBV DNA levels were measured by real-time RT-PCR. Data are presented as the mean ± SD of three independent experiments. *p < 0.05 compared to the untreated control.

Figure 2

Replication of both HAV and HBV is inhibited in PXB cells superinfected with HAV and HBV compared to those monoinfected with HAV or HBV. (A) HAV RNA levels in PXB cells infected with HAV only and those superinfected with HAV and HBV genotype C. After 5 days of HBV infection, PXB cells were infected with the HAV HA11-1299 strain. Three days after infection with HAV, cellular RNA was extracted, and HAV RNA levels were measured using real-time PCR. (B) HBV DNA levels in PXB cells infected with HBV alone and those superinfected with HAV and HBV. After 5 days of HBV infection, PXB cells were infected with the HAV HA11-1299 strain. Three days after infection with HAV, cellular RNA was extracted, and HBV DNA levels were measured using real-time PCR. Data are presented as the mean ± SD of three independent experiments. *p < 0.05 compared to the untreated control.

Figure 3

Inhibitory effects of Japanese rice-koji miso extracts on HAV replication in HepG2.2.15 cells infected with HAV. (A) HAV RNA levels (B) HBV DNA levels. After 72 hours of HAV HA11-1299 strain infection, cells were treated or not with Japanese rice-koji miso extracts [0.5% Kurasaigetsuusujiomiso (KU), Ando Brewery Kakunodate, Japan]. After 96 hours of infection, total cellular RNA and DNA were extracted for further analysis. HAV RNA and HBV DNA levels were measured using real-time PCR. Data are presented as the mean ± SD of three independent experiments. *p < 0.05 compared to the untreated control.