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Swine fever (Classic Swine Fever, CSF) is a swine highly contagious disease caused by swine fever virus (Classic Swine Fever virus, CSFV), the World Organisation for Animal Health (Office International des Epizoofies, OIE): as a must one of informed infectious diseases. Swine fever Shimen strain is virulent strains isolated in China earlier standards, rabbit fever is not caused; classical swine fever (Hog Cholera Lapinized Virus, HCLV) vaccine of attenuated vaccine strains with independent intellectual property rights in China (internationally known as C strains), its ability to grow in the cells on the difference can cause the rabbit fever; France CSFV T strain is a cryogenic mutagenesis attenuated strains, which grow well on cells, does not cause the rabbit body heat. In this study, the use of reverse genetics, the T strain infectious clone constructed in our laboratory based, build two chimeric virus plasmid pCT and pSMT of and successfully rescue two the chimeric virus vCT and vSMT through them thermal response characteristics of the cells on the growth characteristics and rabbit explore the relationship between classical swine fever virus structural proteins and cell growth characteristics as well as rabbit fever reaction. Research the swine fever lapinized weak strain of CSFV Shimen strain and the T strain structural proteins and biological characteristics of the relationship, the study constructed two chimeric virus. By comparing the NCBI C strain of swine fever virus has been published at home and abroad, the full genome sequence of the T strain of swine fever virus Shimen strain and save the laboratory, in the structure of protein sequences in the design and synthesis of three pairs of common primers by RT- PCR amplified and access to the full-length structure of protein sequences of the rabbit of weak strains and swine fever Shimen strain. CSFV T strains of full-length infectious clone based on the structural protein gene of CSFV T cell line respectively with swine fever structural protein gene and swine fever Shimen attenuated vaccine strain C strains virulent strain of the structural protein gene replacement construct two embedded co-infection cloning plasmid pCT and pSMT, the groups of enzymes double digestion to determine the the chimeric success. BHK-21 cells electroporation SK6 cell electroporation method, successfully rescued the two the chimeric virus vCT and vSMT, worked out SK6 cell electroporation save the test conditions for the virus. PFU titer, chimeric viruses for virus passaged the CSFV virus antigen detection ELISA, and the passaged virus and infected cells by conventional virus passaged virus transmission two methods explore the optimal conditions for virus replication, and results showed that the infected cell passaging The virus titer higher than conventional virus passaged virus titer, each generation passaged virus PFU and ELISA results are consistent. Immunohistochemistry, RT-PCR, and sequencing are three ways to confirm passaged virus vCT, vSMT mutation and variation. Through comparison vCT, vSMT vT growth characteristics in cell reveals lapinized attenuated strain of classical swine fever Shimen strain structural proteins decided CSFV growth characteristics of the cells in a certain extent. To study the relationships between the the CSFV virus structural proteins and the thermal reaction in rabbits, rabbits were divided into five groups. The first group, two rabbits, each intravenous 50RID, C strains of rabbit tissue toxicity; second group, two rabbits, each intravenous injection 2ml normal cell supernatant; third group, five rabbits, each vein the injection 107PFU T strains of poison; fourth group, three rabbits, each intravenous injection of 1.8 × 103PFU vCTFO; the fifth group 3 rabbits, each intravenous injection of 103 PFU vCTF1. Body temperature test results show vCT and control C drug can cause rabbit fever rabbit fever reaction vT not cause rabbits thermal reaction. Thus, of CSFV C strain structural proteins with rabbit fever reaction are closely related. For the study of the chimeric virus vCT reproductive characteristics in rabbits, collecting rabbit serum samples, spleen, lymph nodes and other organs, with 4% paraformaldehyde, embedded in paraffin, HE and immunohistochemical staining, the sample was observed clinical symptoms and pathological necropsy changes, histopathological changes, detection of specific viral antibodies, the results showed that the spleen bleeding, red blood cell deformability, the red pulp local visible granulosa cells, white pulp area significantly reduced, lymphocytosis, lymph node by a large number of large lymphatic cell infiltration, the basic positive material distribution site in the lymph node medulla and spleen red pulp positive cells consist primarily of reticular cells, some lymphocytes. This suggests that the chimeric virus vCT in rabbit breeding, causing tissue damage and the body's immune response. Collectively, these results show that, the swine fever lapinized attenuated strain, swine fever Shimen virulent strain of structural proteins determines the classical swine fever virus in the cells on the growth characteristics of classical swine fever rabbits attenuated strain structural proteins of rabbit fever reaction, attenuated classical swine fever strains chimeric virus in rabbits can multiply. To further enhance the swine fever rabbits attenuated strain vaccine cell culture capacity, improved DIVA vaccine in the the swine fever lapinized strain vaccine production technology, research and development, these lay a certain foundation.
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