迟缓爱德华菌菌蜕疫苗对罗非鱼注射和口服免疫的效果分析

通过腹腔注射、口服两种免疫途径探讨迟缓爱德华菌菌蜕疫苗对罗非鱼Oreochromis niloticus的免疫保护效果。将制备的迟缓爱德华菌菌蜕疫苗（ETG）和福尔马林灭活疫苗（FKC）采用腹腔注射、口服两种免疫途径免疫罗非鱼，分别于免疫后14d、21d和28d采集罗非鱼血清、头肾、脾脏，测定血清中抗体IgM水平，血清中酸性磷酸酶（ACP酶）、超氧化物歧化酶（SOD酶）活性及罗非鱼头肾和脾脏中白介素（IL-1）、肿瘤坏死因子（TNF）、干扰素（IFN）、Caspase3等细胞因子的相对表达量，并通过攻毒试验得到菌蜕疫苗、福尔马林灭活疫苗两种疫苗的相对免疫保护率。免疫组罗非鱼的血清抗体水平均极显著高于（P<0.01）对照组，ETG注射组抗体效价极显著高于（P<0.01）FKC口服组。免疫28d，免疫组SOD、ACP酶活力显著高于（P<0.05）对照组（Group E、F）；在头肾中，免疫组（Group A、B）TNF、IL-1和IFN的相对表达量显著高于（P<0.05）对照组（Group E、F）。在免疫保护试验中，所有免疫组的免疫保护率均显著高于（P<0.05）对照组，注射、口服菌蜕疫苗的相对保护率分别为79%、77%，注射、口服灭活疫苗组的的相对保护率分别为62%、60%，但两种疫苗免疫保护率无显著差异。试验研制的菌蜕疫苗得到更高的免疫保护率，菌蜕疫苗在预防罗非鱼爱德华菌病中有良好的研究价值和应用前景。

IMMUNE EFFICACY OFEDWARDSIELLA TARDA GHOSTS VACCINE FOR OREOCHROMIS NILOTICUS BY DIFFERENT INOCULATION ROUTES

Bacteria ghosts is a new type vaccine, which can induce strong cellular immunity, humoral immunity and mucosal immunity. This study explored the immune efficacy ofEdwardsiella bacteria ghosts (ETG) and Formalin killed cell (FKC) vaccinatedOreochromis niloticus by intraperitoneal injection and oral routes. Serum at 14, 21, 28 day post-vaccination were collected to analyze specific IgM antibody, acid phosphatase (ACP), superoxide dismutase (SOD), and head kidney and spleen were used to measure the expression of IL-1, TNF, IFN, Caspase3, and immunolo-gic potency (relative percent survival, RPS) was calculated. Our results indicated that vaccine groups had significantly increased (P<0.01) specific antibody levels compared with control at 28 days post-secondary vaccination, and ETG in-traperitoneal injection group had significantly higher antibody levels (P<0.01) than FKC oral group. Superoxide en-zyme (SOD) activity and acid phosphatase (ACP) of vaccinated groups were significantly higher (P<0.05) than those of the control groups (Group E and F), and the vaccine trials group (Group A and B) and TNF, IL-1 and IFN were signifi-cantly higher (P<0.05) than those of the control (Group E and F) at 28 day post-vaccination. The relative protective sur-vival (RPS) of all vaccine groups was significantly higher (P<0.05) than that of the control groups. RPS of ETG injec-tion and ETG oral were 79% and 77%, respectively, and RPS of FKC injection and FKC oral were 62% and 60%, re-spectively. However, they were no significant difference between ETG and FKC. These results suggest that bacteria ghost is good candidate in preventingEdwardsiella tarda disease inOreochromis niloticus with great research value and application prospects.