Infection of Owl Monkeys (Aotus trivirgatus) and Cynomolgus Monkeys (Macaca fascicularist) with Hepatitis E Virus from Mexico

Owl and cynomolgus monkeys were inoculated with hepatitis E virus (HEV) to compare disease models and produce antibody and virus. By immune electron microscopy (IEM), all six owl monkeys were shown to have serologic responses manifested by unusually high levels of antiHEV at 6 months, but only three developed hepatitis. Virus-related antigen in liver (HEVAg) was detected by immunofluorescence microscopy of biopsies from two of four owl monkeys; one with HEVAg also had HEV in acute-phase bile (detected by IEM) and feces (detected by infecting another owl monkey). In contrast, cynomolgus monkeys propagated HEV to higher levels and all five had hepatitis. Moderate-to-high levels of HEVAg correlated with detectable HEV in bile for both species. Thus, the value of using HEV-infected cynomolgus was confirmed. Owl monkeys were shown to be HEV-susceptible and sources of high-level anti-HEV; Sustained anti-HEV in these monkeys may also be useful for understanding immune responses.