Experimental transfection of Macaca sylvanus with cloned human hepatitis B virus

Abstract

Due to the absence of easily accessible animal models for the study of hepatitis B virus (HBV), the possibility of using Macaca sylvanus, a monkey originating from Morocco, North Africa, was investigated. Three monkeys were intrahepatically inoculated with a replication-competent head-to-tail HBV DNA plasmid dimer construct. The HBV surface antigen and HBV DNA were detected prior to alanine aminotransferase elevation in the serum of two of three HBV-inoculated monkeys at day 2 post-transfection and persisted for several weeks. This indicates that transfected animals developed markers of HBV infection. In addition, electron microscopy of the serum 3 weeks post-transfection showed the presence of virus particles whose shape and size were similar to complete 42 nm HBV Dane particles. Histological examination of liver tissues also revealed pathological changes not observed in uninfected controls, which strongly suggested acute hepatitis. HBV DNA was also detected by PCR in these monkey livers. Taken together, these results indicate that HBV can successfully replicate in this model and that M. sylvanus could be a potentially useful new primate model for the study of HBV replication.In spite of the availability of an effective vaccine, infection by hepatitis B virus (HBV) remains a worldwide public health problem, with 400 million chronic HBV carriers. Every year, nearly 1 million individuals succumb to HBV-associated liver disease, especially cirrhosis and hepatocellular carcinoma

Discovery of naturally occurring transmissible chronic hepatitis B virus infection amongMacaca fascicularisfrom mauritius island

“…Presence of HBV DNA was tested in macaque serum using polymerase chain reaction (PCR), followed by southern blotting analysis. Primers for PCR amplification were selected from sequences overlapping the core and surface genes that are highly conserved among all human HBV genotypes and NHP HBV‐like viruses …”

“…Our previous studies already opened the possibility of using macaques for HBV studies, which are the NHPs most commonly used in biomedical research. We have demonstrated both successful in vivo HBV transfection and in vitro HBV transduction with baculovirus vector in macaques, although only transient viral infection could be generated by this method in these animals …”

Macaque Models of Human Infectious Disease

“…Rhesus macaques can be experimentally infected with human HBV with no evidence of liver damage (Barker et al 1975;Zuckerman et al 1975). However, macaques from Morocco (M. sylvanus) developed liver pathology after intrahepatic inoculation with a replication-competent HBV DNA plasmid construct (Gheit et al 2002). Highly effective HBV vaccines have been licensed since 1982, so there is no need for an animal model for this virus.…”

Occult HBV infection in Morocco: from chronic hepatitis to hepatocellular carcinoma

“…A 420-bp fragment of the X gene was amplified following seminested PCR described by Uchida et al (15) using primers P197 and P201 for the first PCR and primers P198 and P201 for the second PCR. A 145-bp fragment in the core gene was amplified using primers and PCR conditions previously described by Gheit et al (16). The detection limit of these assays was 10 copies/reaction.…”