Reverse transcription polymerase chain reaction (RT-PCR) was used for the detection of classical swine fever virus (CSFV) in blood and tissue samples of field cases and experimentally inoculated pigs. The distribution...Reverse transcription polymerase chain reaction (RT-PCR) was used for the detection of classical swine fever virus (CSFV) in blood and tissue samples of field cases and experimentally inoculated pigs. The distribution of CSFV in different organ samples showed some discrepancies in infected pigs. Four weaner pigs were inoculated with C-strain vaccine virus, then samples of spleen, tonsil, lung, mesenteric lymph node, kidney and brain were collected after slaughter and tested for E2 and NS5B genes using one-step RT-PCR and nested RT-PCR. Using the same method, 12 field cases were simultaneously studied. A discrepancy of CSFV in different samples was found upon detecting the target gene. The most reliable diagnostic organs were spleen and tonsil, and the nested RT-PCR assay provided a highly sensitive and specific method with comparable performance to the one-step RT-PCR assay.展开更多
E2 is an envelope glycoprotein of Classical swine fever virus (CSFV) and contains sequential neutralizing epitopes to induce virus-neutralizing antibodies and mount protective immunity in the natural host. In this stu...E2 is an envelope glycoprotein of Classical swine fever virus (CSFV) and contains sequential neutralizing epitopes to induce virus-neutralizing antibodies and mount protective immunity in the natural host. In this study, four antigen domains (ABCD) of the E2 gene was cloned from CSFV Shimen strain into the retroviral vector pBABE puro and expressed in eukaryotic cell (PK15) by an retroviral gene expression system, and the activity of recombinant E2 protein to induce immune responses was evaluated in rabbits. The results indicated that recombinant E2 protein can be recognized by fluorescence antibodies of CSFV and CSFV positive serum (Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China) using Western blot, indirect immunofluorescence antibody test (IFAT) and ELISA, Furthermore, anti-CSFV specific antibodies and lymphocyte proliferation were elicited and increased by recombinant protein after vaccination. In the challenge test, all of rabbits vaccinated with recombinant protein and Chinese vaccine strain (C-strain) were fully protected from a rabbit spleen virus challenge. These results indicated that a retroviral-based epitope-vaccine carrying the major antigen domains of E2 is able to induce high level of epitope-specific antibodies and exhibits similar protective capability with that induced by the C-strain, and encourages further work towards the development of a vaccine against CSFV infection.展开更多
基金supported by the grants from the National"863" Programme (2006AA10A2041)Development Programme of Science and Technology,Chengguan District of Gansu province (08-5-4)
文摘Reverse transcription polymerase chain reaction (RT-PCR) was used for the detection of classical swine fever virus (CSFV) in blood and tissue samples of field cases and experimentally inoculated pigs. The distribution of CSFV in different organ samples showed some discrepancies in infected pigs. Four weaner pigs were inoculated with C-strain vaccine virus, then samples of spleen, tonsil, lung, mesenteric lymph node, kidney and brain were collected after slaughter and tested for E2 and NS5B genes using one-step RT-PCR and nested RT-PCR. Using the same method, 12 field cases were simultaneously studied. A discrepancy of CSFV in different samples was found upon detecting the target gene. The most reliable diagnostic organs were spleen and tonsil, and the nested RT-PCR assay provided a highly sensitive and specific method with comparable performance to the one-step RT-PCR assay.
基金The National "973" (2005CB523201)Key Technology R&D Programme (2006BAD06A03)
文摘E2 is an envelope glycoprotein of Classical swine fever virus (CSFV) and contains sequential neutralizing epitopes to induce virus-neutralizing antibodies and mount protective immunity in the natural host. In this study, four antigen domains (ABCD) of the E2 gene was cloned from CSFV Shimen strain into the retroviral vector pBABE puro and expressed in eukaryotic cell (PK15) by an retroviral gene expression system, and the activity of recombinant E2 protein to induce immune responses was evaluated in rabbits. The results indicated that recombinant E2 protein can be recognized by fluorescence antibodies of CSFV and CSFV positive serum (Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China) using Western blot, indirect immunofluorescence antibody test (IFAT) and ELISA, Furthermore, anti-CSFV specific antibodies and lymphocyte proliferation were elicited and increased by recombinant protein after vaccination. In the challenge test, all of rabbits vaccinated with recombinant protein and Chinese vaccine strain (C-strain) were fully protected from a rabbit spleen virus challenge. These results indicated that a retroviral-based epitope-vaccine carrying the major antigen domains of E2 is able to induce high level of epitope-specific antibodies and exhibits similar protective capability with that induced by the C-strain, and encourages further work towards the development of a vaccine against CSFV infection.