Pathological characteristics of coxsackievirus A14 in neonatal mice model

In recent years, with the increasing incidence of other non-EV-A71 enteroviruses, the research on other enteroviruses has become more and more important. Coxsackievirus A14 (CVA14), A member of the enterovirus group A, causes hand-foot-mouth disease (HFMD), aseptic meningitis and acute abdominal pain. In this study, we established the first ICR mouse model of CVA14 infection. The CVA14 HE27 strain was selected to infect neonatal mice through a preliminary experiment, and the infection model was established according to three different conditions of infection dose, route and age. It was found that 2-day-old ICR neonatal mice showed clinical symptoms such as hind limb paralysis and death after intramuscular injection of 105.75 TCID50 CVA14 HE27 strain. Through daily monitoring, we found that the viral load of skeletal muscle was the highest, and there were certain pathological changes in various tissues and organs, among which the changes of brain and skeletal muscle were the most obvious. The expression of pro-inflammatory cytokines IL-4, IL-10, IFN-γ and TNF-α were abnormally high. This neonatal mouse model of CVA14 infection will be useful for the development of prophylactic and therapeutic multivalent vaccines, as well as for the screening of antiviral drugs against enterovirus.