Abstract：
Largemouth bass (Micropterus salmoides) has emerged as a significant economic fish species, with a rise in Aeromonas veronii infections in farming. However, research on adjuvants for vaccines against A. veronii in largemouth bass remains scarce. In present study, recombinant largemouth bass IL-1β (LbIL-1β) was expressed to explore its adjuvant effect on the A. veronii inactivated vaccine. Following vaccination with recombinant LbIL-1β (rLbIL-1β) and the inactivated A. veronii, higher serum SOD levels and lysozyme activities were observed in largemouth bass from inactivated A. veronii + rLbIL-1β vaccinated group. Furthermore, it was discovered that rLbIL-1β was able to boost the serum-specific antibody levels induced by the inactivated A. veronii. The qRT-PCR analysis revealed that rLbIL-1β also enhanced the expression of IgM, CD4, and MHC II in largemouth bass triggered by the inactivated A. veronii. After challenged with live A. veronii, the outcomes demonstrated that the relative percentage survival (RPS) for largemouth bass resulting from the inactivated A. veronii in combination with rLbIL-1β was 76.67 %, surpassing the RPS of 60 % in the inactivated A. veronii group. Collectively, these findings indicate that rLbIL-1β enhances the protective effect of the A. veronii inactivated vaccine on largemouth bass, showcasing potential as an adjuvant for further development.
摘要：
大嘴鲈鱼（Micropterussalmoides）已成为重要的经济鱼类，随着农业中Veronii气单胞菌感染的增加。然而,对大口鲈鱼中的维龙氏杆菌疫苗佐剂的研究仍然很少。在目前的研究中,表达重组大口鲈鱼IL-1β（LbIL-1β），以探讨其对D.veronii灭活疫苗的佐剂作用。在用重组LbIL-1β（rLbIL-1β）和灭活的A.veronii疫苗接种后，在灭活的A.veroniirLbIL-1β疫苗接种组的大嘴鲈鱼中观察到较高的血清SOD水平和溶菌酶活性。此外，发现rLbIL-1β能够提高灭活的维氏A.veronii诱导的血清特异性抗体水平。qRT-PCR分析显示rLbIL-1β也增强了IgM的表达，灭活的维龙氏A.触发的大口鲈鱼中的CD4和MHCII。在被活的A.veronii挑战后，结果表明，灭活的维龙氏A与rLbIL-1β联合产生的大嘴鲈鱼的相对存活率（RPS）为76.67％，在灭活的A.veronii组中超过60％的RPS。总的来说，这些发现表明rLbIL-1β增强了A.veronii灭活疫苗对大口鲈鱼的保护作用，展示了作为进一步发展的佐剂的潜力。
