维氏气单胞菌菌蜕疫苗免疫后鲤免疫应答与hepcidin基因表达特征

Effect of injection immunization with Aeromonas veronii ghosts on immunological responses and hepcidin gene expression in common carp

摘要:

【目的】为探讨接种维氏气单胞菌菌蜕疫苗后鲤的应答反应特征及与甲醛灭活苗的效果比较，在实验条件下研究了接种疫苗后鲤(Cyprinus carpio)的特异性、非特异性免疫指标及hepcidin基因表达量的变化。【方法】在开始实验的第1、15和29天使用菌蜕疫苗(CLGs)和甲醛灭活疫苗(FKC）对鲤进行注射3次免疫，并设一个注射磷酸缓冲液(PBS)的对照组，每个组设3个重复。从第一次免疫后每隔7 d从每个重复中随机取三尾鱼进行取样，对血清抗体滴度、相对免疫保护率(RPS)、溶菌酶(LZM)、呼吸暴发、补体C3、髓过氧化物酶(MPO)、丙二醛(MDA)及hepcidin基因表达量进行测定。【结果】二次免疫后，CLGs组抗体凝集效价达26?28，显著高于FKC和PBS组(P<0.05)，且其呼吸暴发、LZM、MPO含量和hepcidin基因表达量显著高于PBS组(P<0.05)，MDA含量显著低于PBS组(P<0.05)；CLGs组C3含量在35和42 d显著低于PBS组(P<0.05)；FKC组MPO含量和hepcidin基因表达量显著低于菌蜕组(P<0.05)。CLGs组的RPS为57.70%，FKC组RPS为30.77%。【结论】接种一定强度维氏气单胞菌菌蜕疫苗，能够提高鲤血清抗体效价和呼吸暴发、LZM、MPO等非特异性免疫指标及hepcidin基因表达，而且整体免疫效果好于甲醛灭活苗。

Abstract:

[Objective] To explore the immunological responses of common carp (Cyprinus carpio) after being vaccinated with Aeromonas veronii ghosts and formalin inactivated A. veronii vaccine. [Methods] The experiment was consisted of three treatments and conducted in cylindrical fiberglass tanks (260 L/tank): CLGs group injected with CL0901 ghost vaccine, FKC group with formalin killed cell vaccine and the control group with phosphate buffer solution (PBS). All treatments were injected on 1st, 15 th and 29 th day after the experiment started. Three fish in each tank were sampled for blood and tissue at every 7 days after the first inoculation. The evaluation parameters included the serum antibody titer, relative percent survival (RPS), lysozyme (LZM), respiratory burst, complement protein 3 (C3), myeloperoxidase (MPO), malonic dialdehyde (MDA) and relative expression content of hepcidin gene. [Results] After the secondary inoculation, the antibody titer in CLGs group reached 26?28, and it was significantly higher than that in other groups (P<0.05). The respiratory burst, serum LZM, MPO and expression of hepcidin gene of CLGs group were significantly higher than those of PBS group (P<0.05). C3 in CLGs group was significantly lower than that in PBS group on 35 and 42 d (P<0.05). The MPO and expression of hepcidin gene of FKC group were significantly lower than those of CLGs group (P<0.05). The RPS was 57.70% in CLGs group, but 30.77% in FKC group. [Conclusion] These results indicated that the CLGs could enhance the serum antibody titer, respiratory burst, lysozyme, myeloperoxidase and relative expression content of hepcidin gene. As a whole, the effect of immune protection of CLGs is better than that of FKC.