Abstract:

Objective   To study the characteristics of enterovirus 71(EV71)isolates in vivo, and to provide information for the research of EV71. Methods   One-day old BALB/c mice were infected with  6 EV71 strains isolates, and symptoms were observed. All mice were sacrificed at 7d after the infection to collect organs and tissues for the pathological examination, RT-PCR detection and immunohistochemistry. Results   6 viruses were isolated from stool samples, and identified as C4 genotype of EV71. All of them could induce lesions of one-day old mice. The JN200804 strain induced flaccid paralysis on mice 5 days after the infection. Histopathologically, lymphocytic infiltration and some other pathologic changes were observed in the infected mice brain, lung and skeletal muscles. mRNA and antigens was detected in the brain of mice infected with JN200804. Conclusion   6 strain of EV71 isolates can cause the disease on BALB/c mice, including the paralysis, muscular tremor, and death of infected mice.

Key words:  Enterovirus C, human; Immunohistochemistry; Reverse transcriptase polymerase chain reaction; Genes; Mice, inbred BALB C