Study On The DNA Vaccine Of Pseudomonas Aeruginosa FlgE Gene

Pseudomonas aeruginosa(P.a)is a conditional pathogen,which is widely existing in air,water and soil.It can cause animal sepsis,bacteremia,pyogenic pneumonia and other diseases.It also can cause human burn infection and empyema.With the continuous expansion of intensive,the incidence of primary diseases of P.a has of late years increased significantly,which often causes large outbreaks of young livestock and poultry.At present,the prevention and treatment of P.a mainly depends on longterm,high-dose use of antibiotics and other chemical drugs.It has been found that P.a has broad-spectrum resistance.Most of its antiseptics and antimicrobial agents are manifested as natural or acquired multiple drug resistance,resulting in fewer and fewer effective antimicrobial agents available for infection,which makes the clinical treatment more difficult.So the development of effective antimicrobial agents Practical vaccines,convenient,safe and effective immunization procedures will be the most effective and economical way to prevent P.a infection.flgE may be a virulent factor in the flagellum of P.a that has not been recognized except the flagellum component protein FliC.flgE has strong immune stimulation.It can induce the body to produce a strong immune response.In this study,the flgE gene was used as the research object.The target gene was amplified by PCR and cloned into eukaryotic expression vector pcDNA3.1(+)to construct the recombinant plasmid pflgE.BALB/c mice were divided into seven groups: DNA vaccine group,DNA vaccine inulin group,DNA vaccine inulin as adjuvant group,oil emulsion inactivated vaccine,oil emulsion flagellin vaccine,pcDNA3.1(+)empty vector group and PBS negative control group.Immunization was given every two weeks,three times in total.The feed intake and body weight of mice were measured,food conversion rate was calculated,serum antibody level was detected by indirect ELISA,lymphocyte proliferation was detected by MTT,IFN-gamma secretion level was detected by kit method.Mice were attacked by P.a.Survival number and protection rate were calculated.The DNA vaccine with the best immune effect was immunized to mice at different doses,the serum antibody level of immunized mice was detected,and the cell immune response level induced by the vaccine was detected by lymphocyte proliferation test,and the protective rate of each group was calculated to determine the optimal immune dose.The results showed that DNA vaccine had immune effect,but the immune effect was not as good as inactivated vaccine and flagellin vaccine.The DNA vaccine inulin as adjuvant had the best immune effect,and the optimal immune dose was 20%.The DNA vaccine of flgE gene studied in this paper can lay a foundation for the follow-up study of Pseudomonas aeruginosa vaccine.