3 ǀ HEV ANIMAL MODELS
In vivo studies on HEV infection have long been hindered due to
many issues such as the lack of a small animal model. Recently, to study
the HEV infection human liver chimeric mice were
used.85 For some HEV strains, the cell culture system
has been established such as genotype 3, genotype 4, and genotype 1,
among these genotypes the genotype 1 replicate poorly in vitrosystem. The best animal models to study HEV infection are pigs and
non-human primates (NHPs) such as African green monkeys, chimpanzees,
cynomolgus monkey, owl monkeys, squirrel monkeys, rhesus macaques,
vervets, tamarins, but some issues like finance and research ethics
restrict the use of these models in research. Therefore, much attention
has been paid to the development of small animal models to study the HEV
infection properly, examine cross-species transmission, elucidate virus
and host interaction, testing the potential and efficacy of HEV
vaccines, and analyze adverse outcomes.86
From pregnant mice tissues (liver, spleen, kidney, colon, uterus, and
placenta), the establishment of the HEV infection was confirmed by
detection of HEV RNA. The results showed that the HEV infection was
successfully established with a high rate of miscarriage (7/8, 87.5%)
in the middle of pregnancy. To study the HEV infection in pregnant
women, this animal model can be used to study the HEV adverse outcomes,
pathogenesis, and host response. This model may be useful for future
anti-HEV drug development.87