Hantavirus Infection Of Primary Cultured Cortical Neuron Induces Apoptosis

Hantavirus, belonging to Bunyaviridae family, with certain hantavirus species cause human disease as hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). HFRS is caused by pathogenic Hantavirus species like Hantaan virus (HTNV), Seoul virus (SEOV), Dobrava virus (DOBV), and Puumala virus (PUUV). HTV infected abroad range of organs and cells in vivo, and brain is one of the sensitive target organs. Our previous work showed that HTV cause a lethally infection in newborn suckling mice, the viral antigen and RNA can be detected in the cytoplasm of neurons in cerebral cortex and hippocampus. To explore the direct effect of HTV infection on neuron, the primary cortical neuron cultures of newborn mice and rats, less than 24hr of age, was prepared for HTNV 76-118 strain and SEOV L99 stain infection in vitro. After 1, 2, 3, 4, 5, 6 and 7 d post infection, the cultures were harvested for immunohistochemical detection of virus nucleocapsid protein, RT-PCR, Real-time PCR and Western blot. The results showed that the HTV NP and HTV S segment were progressively and significantly increased in a time-dependent manner (P<0.01). Our results proved in vitro evidence that neuron is target of HTV infection, and HTV can duplicate and propagate in neuron. Then we detect apoptosis by Hoechst staining, TUNEL, cell death ELISA detection and some apoptosis related gene and protein. Our results confirmed HTV induces apoptosis through p53 mediated mitochondrial pathway. Our study provide a good evidence for further study of pathogenesis of HFRS central symptom .