| Eimeria acervulina is moderate virulence and in the small intestine parasite coccidia, in the chicken industry of the intensive chicken farm is highest prevalence and second only to Eimeria harm. Studies have shown that E. acervulina can be associated with of E .tenella caused mixed infection and clinical type, while the main infection caused by subclinical coccidiosis of the chicken industry ,Sometimes, clinical loss larger, which aroused great attention and extensive research was carried out. It has been approved that stimulating the cell immuno-reaetion of the host is an effeetive approach to Prevent avain coccocidiosis.A Prominent advantage of DNA vaccine as athird generation of vaccine is that it can induce abroad cell immuno-reaetion and form Perdured immune memory. the DNA vaccine Which was constructed by special antigen has more effect and Prospect in the anticoccocidiosis Practice.in this investigation we inserted the 3-1E antigenic geneof E.acervulina into the vector pcDNA3.1 to successfully construct plasmid DNA vaccine pcDNA-3-1E.The Protective effeets the above mentioned DNA plasmid pcDNA3.1-3-1E Were tested in the Protective experiment of chickens against the E.acervulina, it turn out that the DNA plasmid has fine protective effectiveness. This study basis on it , with the pcDNA3-3-1E immune chicks, its safety and immune responses were evaluated. Specific methods are as follows:The recombinant plasmid pcDNA3-3-1E was injected into Avian chicken by intramuscular route.Various tissues were removed from Avian chicken at 1,5,15,30,60 days postinjection(dp)To studied the distribution of their organization and the clinical symptom of immunized Avian chicken were surveyed. 3-1E gene fragments were amplified in every tissues of injectionsite at 1,5,15 days postinjection, but they were amplified only in the muscular tissues of injectionsite at 30 and 60 days postinjection.In this stuty, plasmid DNA at dose of 50μg had no obvious adverse effects. The recombinant plasmid pcDNA3-3-1E can exist in every tissues at least 15 days.Except for the site of administration, plasmid DNA is no longer detectable in tissues after30 days postadministration, clinical manifestation not detected abnormalitily.The DNA plasmid pcDNA3-3-1E was injected into Avian chicken by intramuscular route. Samples was taked at 1, 5, 15, 30, 60 days postinjection. using PCR analyse the integration situation of plasmid DNA and the host cell genome.the same time take sheds faeces to analyse the possibilities of environmental transfer and diffusion. plasmid DNA was not found in the host cell genome and not detected in the external environment. Acute toxicity tests are located dose 0μg, 50μg, 100μg, 2500μg of four dose groups, then observed mortality, body weight changes and serum biochemical in the eight cases within 14 days after vaccination, chickens without death, in (P <0.05) level ,the was no significant changes in every group. Show that the DNA plasmid pcDNA3-3-1E on the chicken and the environment are safe.The recombinant plasmid pcDNA3-3-1E was injected into Avian chicken by intramuscular route.then observed the conditions of cellular immunity and humoral immunity.compared with the empty plasmid group and the healthy control group, IL-2, IFN-γand IgG levels of peripheral blood were significantly higher in (P <0.05) and lymphocytes significantly increased value-added (P <0.05) in vector group , showed that pcDNA3-3-1E naked plasmid DNA vaccine can effectively improve the cellular immune chickens and humoral immunity.
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