壳聚糖和普朗尼克介导猪白细胞介素-23基因体内表达对PRRSV疫苗的免疫增强效应

摘要

Porcine reproductive and respiratory syndrome (PRRS) is a severe, economically important infectious disease of pigs.Current vaccines to control the disease, however, are inadequate due to low immunity;and the present study was conducted to explore an effective adjuvant to enhance the immunological efficacy.A recombinant plasmid containing the porcine IL-23 gene was encapsulated in chitosan nanoparticles and Pluronic-L64 designated as VRIL23-CNP-Pluronic, which was tested following intramuscular injection of 28 day-old mice in comparison with VR1020-Pluronic as the control.Over a 35 day observation period, PRRSV-specific antibody, IgG1 and IgG2 a titers, CD4+ and CD8+ T cells increased significantly in the treated mice (P<0.01).As analyzed by qRT-PCR, expression levels of IL-23, TLR1, TLR6, STAT1, IL-10, TNF-α, IL-15 and CD62 L genes were also significantly up-regulated in comparison with those of control mice (P<0.01).These results show that co-injection of VRIL23-CNP-Pluronic with PRRS vaccine enhances both innate and adaptive immunity of mice, and provide support for its development as a novel vaccine adjuvant for control of swine PRRS.%猪繁殖和呼吸综合征 (PRRS) 是一种严重影响养猪业的高度传染性疾病, 目前预防这种疾病的疫苗免疫还存在一定缺陷.本研究旨在探索一种有效的佐剂以提高其免疫效力.将猪IL-23基因重组质粒用壳聚糖和普朗尼克材料包裹制成纳米颗粒, 命名为VRIL23-CNP-Pluronic.将28日龄小鼠分为两组, 分别肌肉注射VRIL23-CNP-Pluronic (实验组) 和VR1020-Pluronic (对照组), 两组均同时接种PRRSV疫苗, 在接种后第0、7、14、28和35天采集血样并分析免疫变化.实验组中PRRSV特异性抗体、IgG1和IgG2a水平、CD4+和CD8+T淋巴细胞数量均极显著高于对照组 (p<0.01) ;经qRT-PCR分析, 与对照组相比, 实验组小鼠的IL-23、TLR1、TLR6、STAT1、IL-10、TNF-α、IL-15和CD62L基因表达水平均极显著上调 (p<0.01) .结果表明, VRIL23-CNP-Pluronic能促进小鼠对PRRSV疫苗的免疫应答, 并为其作为新型PRRSV疫苗佐剂的开发提供理论基础.