Experimental study on the chitosan-DNA vaccines against campylobacter jejuni invasion / 中华预防医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>The immunogenicity and protective efficacy of an experimental Campylobacter jejuni (C. jejuni) chitosan-DNA vaccines were evaluated in mice.</p><p><b>METHODS</b>The chitosan-DNA vaccines were prepared by embedding pcDNA3.1(+)-cadF and pcDNA3.1(+)-peblA with chitosan respectively. BALB/c mice were intranasally immunized in a four-dose primary series (7 d intervals) at doses of 60 microg chitosan-DNA vaccines each time. The comparative immunogenicities of nine formulations were assessed on the basis of the generation of antigen-specific antibodies in serum and intestinal secretions. Mice were attacked repeatedly through intragastric administration of C. jejuni HS19 at the 8th week after the immunization and protective efficacy was determined by detecting the degrees of protection afforded against C. jejuni invaded.</p><p><b>RESULTS</b>The mice immunized with chitosan-DNA vaccines have generated high levels of IgA and IgG from the sera and IgA from the intestinal secretions and the P/N value went up to 20.58, 30.13 and 6.87 respectively. Meanwhile, the expression of intestinal SIgA increased correspondingly. Moreover the chitosan-DNA vaccines induced strongest level of protection in BALB/c mice against challenge with C. jejuni HS19 strain and the protective efficacies was 93.70.</p><p><b>CONCLUSION</b>The results of this study indicate that the chitosan-DNA vaccines could induce significant protective immunity against C. jejuni challenge in the mice model.</p>