Study of coxsackievirus A6 infection in Mongolian gerbils

Abstract

Objective To study infection of coxsackievirus A6 (CV-A6) in Mongolian gerbils. Methods To screen the optimal ages of Mongolian gerbils, five groups with different ages were infected with 1×105 TCID50 dose of CV-A6 XS45 strain by intraperitoneal, and symptom scores of Mongolian gerbils were collected. Then to estimate the dose-effect, three doses of virus were injected to the Mongolian gerbils. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry(IHC) were used to determine virus load and tissues infection in muscle, brain and intestinal tract. Results Mongolian gerbils infected with 1×105 TCID50 dose CV-A6 consistently exhibited clinical signs, and the morbidity (death) rates of five age groups were up to 100%. There was a positive correlation between the trend of symptom scores changes and ages. The morbidity (death) rates of three doses (1×103 TCID50, 1×104 TCID50, 1×105 TCID50) also were up to 100% in 28 days Mongolian gerbils. The correlation between the trend of symptom scores changes and doses were negative. Virus loads were detected in muscle, brain and intestinal tract of pathogenesis animal. The virus loads of muscle were higher than others. IHC results showed virus infection and cytopathic effects in three tissues. Conclusions Mongolian gerbils had high susceptibility to CV-A6, and were best for animal model of CV-A6 infection. Key words: Coxsackievirus A6; Mongolian gerbils; Infection model