Infectious pancreatic necrosis virus (IPNV) primarily infects larvae and young salmonid with serious economic losses, which causes haemorrhage and putrescence of hepatopancreas. To develop a more effective oral vaccine against IPNV infection, the aeromonas hydrophila adhesion (AHA1) gene was used as a targeting molecule for intestinal epithelial cells. A genetically engineered Lactobacillus casei (pPG-612-AHA1-CK6-VP2/L. casei 393) was constructed to express the AHA1-CK6-VP2 fusion protein. The expression of interest protein was confirmed by western blotting and the immunogenicity of pPG-612-AHA1-CK6-VP2/L. casei 393 was evaluated. And the results showed that more pPG-612-AHA1-CK6-VP2/L. casei 393 were found in the intestinal mucosal surface of the immunized group. The Lactobacillus-derived AHA1-CK6-VP2 fusion protein could induce the production of serum IgM and skin mucus IgT specific for IPNV with neutralizing activity in rainbow trouts. The levels of IL-1β, IL-8 and TNF-α isolated from the lymphocytes stimulated by AHA1-CK6-EGFP produced were significantly higher than EGFP group. For transcription levels of IL-1β, IL-8, CK6, MHC-II, Mx and TNF-1α in the spleen, the result indicated that the adhesion and target chemokine recruit more immune cells to induce cellular immunity. The level of IPNV in the immunized group of pPG-612-AHA1-CK6-VP2/L. casei 393 was significantly lower than that in the control groups. These data indicated that the adhesion and target chemokine could enhance antigen delivery efficiency, which provides a valuable strategy for the development of IPNV recombination Lactobacillus casei oral vaccine in the future.

传染性胰腺坏死病毒（IPNV）主要感染幼虫和幼鲑鱼，造成严重的经济损失，从而导致肝胰腺出血和腐烂。为了开发针对IPNV感染的更有效的口服疫苗，嗜水气单胞菌粘附（AHA1）基因被用作肠上皮细胞的靶向分子。构建基因工程干酪乳杆菌（pPG-612-AHA1-CK6-VP2 /干酪乳杆菌393）以表达AHA1-CK6-VP2融合蛋白。通过蛋白质印迹证实目的蛋白的表达，并评估pPG-612-AHA1-CK6-VP2 /干酪乳杆菌393的免疫原性。结果表明，更多的pPG-612-AHA1-CK6-VP2 /干酪乳杆菌在免疫组的肠粘膜表面发现393个。的乳杆菌来源的AHA1-CK6-VP2融合蛋白能诱导产生血清的IgM和皮肤粘液IGT特异于IPNV与彩虹真鳟的中和活性。从AHA1-CK6-EGFP刺激的淋巴细胞中分离出的IL-1β，IL-8和TNF-α水平明显高于EGFP组。对于IL-1β，IL-8，CK6，MHC-II，Mx和TNF-1α的转录水平在脾脏中，该结果表明粘附和靶趋化因子募集更多的免疫细胞以诱导细胞免疫。pPG-612-AHA1-CK6-VP2 /干酪乳杆菌393免疫组的IPNV水平明显低于对照组。这些数据表明，粘附和靶趋化因子可以提高抗原递送效率，这为将来开发IPNV重组干酪乳杆菌口服疫苗提供了有价值的策略。