The immune efficacy of OmpH DNA vaccine from avian Pasteurella multocida / 中国免疫学杂志

ABSTRACT

Objective:To research on protective immunity of omph DNA vaccine against avian Pasteurella multocida in mice.Methods:The omph gene fragment amplified by PCR from avian Pasteurella multocida was cloned into pMD18-T.Subsequently it was subcloned into the eukaryotic expression vector pcDNA3.1(+),and the recombinant plasmid pOMPH was obtained.Then the recombinant plasmid was transfected into SP2/0 cells in vitro.The transcription and expression of target gene were analyzed by RT-PCR,Western blot analysis and indirect immunofluorescence.Three groups of BALB/c mice(n=16) named pOMPH,pCDNA3.1(+) and PBS were intramuscularly vaccinated with the recombinant plasmid,control vector and PBS respectively.The serum antibodies were detected by indirect ELISA.The spleen lymphocyte proliferation (SLP) and secreted IFN-? of spleen were tested by MTT.The mice were challenged with virulent of avian Pasteurella multocida on week 2 post the third immunization,the protection rate were counted.Results:RT-PCR,Western blot analysis and indirect immunofluorescence showed that the omph gene could be transfected into SP2/0 cells in vitro and expressed the target protein.Indirect ELISA showed that the levels of antibodies in pOMPH group were most significantly higher than in the other groups(P