Immunogenicity and protective efficacy of orally administered recombinant Lactobacillus plantarum expressing VP2 protein against IBDV in chicken.

ABSTRACT: AIM:To develop an effective oral vaccine against the very virulent infectious bursal disease virus (vvIBDV), we generated two recombinant Lactobacillus plantarum strains (pPG612-VP2/LP and pPG612-T7g10-VP2/LP, which carried the T7g10 translational enhancer) that displayed the VP2 protein on the surface, and compared the humoral and cellular immune responses against vvIBDV in chickens. METHODS AND RESULTS:We genetically engineered the L. plantarum strains pPG612-VP2/LP and pPG612-T7g10-VP2/LP constitutively expressing the VP2 protein of vvIBDV. We found that the T7g10 enhancer efficiently upregulates VP2 expression in pPG612-T7g10-VP2/LP. Orally administered, pPG612-T7g10-VP2/LP exhibited significant levels of protection (87·5%) against vvIBDV in chickens, indicating improved immunogenicity. Chickens in the pPG612-T7g10-VP2/LP group produced higher levels of interferons (IFN-?) and interleukins (IL-2 and IL-4) than those in the pPG612-VP2/LP group. CD8+ and CD4+ lymphocyte counts indicated greater stimulation in the pPG612-T7g10-VP2/LP group (13·3 and 21·0% respectively) than in the pPG612-VP2/LP group (10·4 and 14·0% respectively). Thus, pPG612-T7g10-VP2/LP could induce strong humoral and cellular immune responses against vvIBDV. CONCLUSIONS:The recombinant L. plantarum that expresses pPG612-T7g10-VP2 is a promising candidate for oral vaccine development against vvIBDV. SIGNIFICANCE AND IMPACT OF THE STUDY:The recombinant Lactobacillus delivery system provides a promising strategy for vaccine development against vvIBDV in chickens.

SUBMITTER: Maqsood I 

PROVIDER: S-EPMC7166448 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature