Clinical and Biological Character in Mouse Models for Middle East Respiratory Syndrome Generated by Transduction with Different Doses of DPP4 Molecule / 病毒学报

In this study, we evaluated the difference ot biological characteristics in the MERS-CoV infected mice model in prior to transduction with different dosage of human DPP4. Firstly, we transduced different dosage of DPP4 (high or low) into mice, and then challenged them with MERS-CoV in order to establish the model. After establishment of mice model, we observed the clinical signs of disease, virus replication, immunopathogenesis and antibody response. The results indicated that the infected mice showed typical pneumonia, virus replication, histological lesions, and neutralizing antibody production. Moreover, the high dosage group was superior to the low dosage group. Fourteen days after infection, the specific antibody to virus structural protein and neutralizing antibody were analyzed, the high dosage group induced higher level antibody. In summary, the MERS-CoV infected mice model were established prior transduction with DPP4, and the level of DPP4 influenced the clinical signs of disease, virus replication and antibody response in this model.

Establishment of interfering RNA library of acetyltransferase genes and its infection of HepG2.2.15 cells / 中华传染病杂志

Objective To construct lentivirus vectors carrying 16 short hairpin RNA (shRNA) expression cassettes targeting histone acetyltransferases and provide a powerful research approach to explore the mechanism of epigenetic genes in regulating hepatitis B virus (HBV).Methods Following the rule of short shRNA primer design,eight-pair primers (A ~ H )for each gene,which had stable interfering efficiency,were designed.The annealed primers were connected to the empty lentiviral vectors of shRNA for transformation.In order to confirm the positive clones,clones were analyzed by real-time polymerase chain reaction (RT-PCR ).Then, qualified plasmids were verified by enzyme digestion technology.Four shRNA lentivirus plasmids against the same gene were mixed to build lentivirus respectively.After the virus transfected into 293T cells for 48 and 72 hours,supernatants were collected to infect HepG2.2.15 cells.The percentage of fluorescent cells were observed and assessed by microscope 72 hours after infection.Results One hundred and twenty-eight lentiviral vectors of RNA interference (RNAi)library were constructed against 16 histone acetyltransferases and more than 80% of HepG2.2.15 cells were infected with lentivirus 72 hours after infection.Conclusions Sixteen shRNA lentivirus vectors against histone acetyltransferase are successfully constructed.Thus,a solid foundation for the study of the effect of human histone deacetylase on HBV replication is established.

Histopathological changes in EV71-infected mouse model:a transmission electron microscopic study / 中华病理学杂志

<p><b>OBJECTIVE</b>To document ultrastructural changes of brain, spinal cord, skeletal muscle, jejunum and lung of EV71 infection mouse model, and to explore the myotropism and pathogenesis of EV71 in nervous system.</p><p><b>METHODS</b>Ten-day-old suckling mice were infected with EV71 strain via the intraperitoneal route. Mice with paralysis were scarified on day 4 post infection and the brain, spinal cord, skeletal muscle, jejunum and lung were sampled for transmission electron microscopy and light microscopy.</p><p><b>RESULTS</b>Lesions in brain were generally mild with inner chamber swelling in some of mitochondria. Myelin sheaths of medullated fibers were split with vacuolated changes. The Nissl bodies in anterior motor neurons disappeared along with mitochondria swelling, rough endoplasmic reticulum swelling and degranulation. Cytoplasm of anterior motor neurons showed cribriform appearance accompanied by neuronophagia. The bands of skeletal muscle in the infected group disappeared with degeneration and karyopyknosis in myocytes, in addition to mitochondrial swelling. Microvilli of epithelium in jejunum became loosely arranged along with formation of spiral medullary sheath structure and mitochondria swelling. Interstitial pneumonia was observed in lungs with type II pneumocyte proliferation and evacuation of the multilamellar bodies.</p><p><b>CONCLUSIONS</b>EV71 infection causes severe myositis in the mouse model suggesting a strong myotropism of EV71 virus. The presence of lesions of various degrees in central nervous system and changes in anterior motor neurons may be associated with limb paralysis.</p>