University of Arkansas, Department of Poultry Science, Fayetteville, AR.
The Ohio State University, Department of Animal Sciences, Columbus, OH.
Poult Sci. 2017 Dec 1;96(12):4352-4360. doi: 10.3382/ps/pex144.
Historically, Salmonella vaccines have been either live attenuated or killed bacterin vaccines that fail to offer cross-serogroup protection, which limits risk mitigation and protection of consumers. Subunit recombinant vaccines which possess highly conserved antigens offer potential to provide cross-serogroup protection, and the ability to express immune-enhancing molecules that promote recognition by the immune system. Six Salmonella subunit vaccine candidates were developed in either attenuated S. Enteritidis (SE) or S. Typhimurium (ST) that cell-surface express antigenic epitopes of high mobility group box 1 immune-enhancing sequence (H), peptidoglycan associated lipoprotein (P), and Omp18 protein Cj0113 (C) in different pattern arrangements for evaluation against S. Heidelberg (SH) challenge in broilers. In exp. 1, chicks were orally vaccinated with SE-CPH, SE-HCP, SE-CHP, ST-CPH, ST-HCP, or ST-CHP at 1 × 107 cfu/chick, or saline on d 1 and d 14. On d 17 all birds were challenged with 6 × 106 cfu/chick SH, and ceca collected on d 23 and d 28. On d 23 only SE-CPH reduced (P < 0.05) SH recovery at 0.34 ± 0.23 log10 cfu when compared to control at 1.19 ± 0.26 log10 cfu. On d 28, SE-CPH and ST-HCP reduced SH recovery at 0.40 ± 0.40 and 0.51 ± 0.26 log10 cfu, respectively in comparison to control at 1.36 ± 0.23 log10 cfu. For exp. 2, chicks were orally vaccinated with 1 × 108 cfu/chick SE-CPH, SE-HCP, SE-CHP or saline on d 1. At d 7 all chicks were orally challenged with 7 × 106 cfu/chick SH and ceca collected on d 28 and d 35. SE-CPH reduced (P < 0.05) SH recovery on d 28 when compared to control (6.16 ± 0.13 vs. 4.71 ± 0.55 log10 cfu). In exp 3, chicks were vaccinated by spray in a commercial vaccination cabinet with SE-CPH vaccination, 1.6 × 107 cfu/chick, or saline. Birds were challenged on d 14 with 3 × 107 cfu/chick SH and ceca collected on d 18 and d 25. SE-CPH reduced SH recovery (P < 0.05) on d 18, 2.75 ± 0.05 log10 cfu, and d 25, 1.89 ± 0.43 log10 cfu, as compared to control chickens at 5.6 ± 0.37 (d 18) and 3.98 ± 0.5 log10 cfu (d 25). The results of these experiments suggest that cross-serogroup protection is possible using these SE and ST-vectored subunit vaccines.
从历史上看，沙门氏菌疫苗要么是减毒活疫苗，要么是死菌疫苗，都不能提供交叉血清群保护，这限制了风险缓解和消费者的保护。具有高度保守抗原的亚单位重组疫苗有可能提供交叉血清群保护，并能够表达增强免疫的分子，促进免疫系统的识别。在实验中，将 6 种沙门氏菌亚单位疫苗候选物分别在减毒的肠炎沙门氏菌（SE）或鼠伤寒沙门氏菌（ST）中开发，这些候选物在不同的模式排列中在细胞表面表达高迁移率族蛋白 1 免疫增强序列（H）、肽聚糖相关脂蛋白（P）和 Omp18 蛋白 Cj0113（C）的抗原表位，用于评估其对鸡 Heidelberg（SH）的挑战。在实验 1 中，小鸡在 1 天和 14 天分别口服 SE-CPH、SE-HCP、SE-CHP、ST-CPH、ST-HCP 或 ST-CHP 疫苗，剂量为 1×107cfu/鸡，或用生理盐水口服。在 17 天，所有的鸡都用 6×106cfu/鸡的 SH 进行攻毒，在 23 天和 28 天收集盲肠。在 23 天，只有 SE-CPH 减少了 SH 回收（P < 0.05），与对照组的 1.19±0.26 log10cfu 相比，回收率为 0.34±0.23 log10cfu。在 28 天，SE-CPH 和 ST-HCP 分别减少了 0.40±0.40 和 0.51±0.26 log10cfu 的 SH 回收，与对照组的 1.36±0.23 log10cfu 相比。在实验 2 中，小鸡在 1 天口服 1×108 cfu/鸡 SE-CPH、SE-HCP、SE-CHP 或生理盐水。在 7 天，所有的鸡都口服 7×106 cfu/鸡的 SH 进行攻毒，并在 28 天和 35 天收集盲肠。SE-CPH 减少了 SH 的回收（P < 0.05），与对照组相比（6.16±0.13 对 4.71±0.55 log10 cfu）。在实验 3 中，小鸡在商业疫苗接种箱中用喷雾接种 SE-CPH 疫苗，剂量为 1.6×107 cfu/鸡，或用生理盐水喷雾接种。在 14 天，鸡用 3×107 cfu/鸡的 SH 攻毒，并在 18 天和 25 天收集盲肠。SE-CPH 减少了 SH 的回收（P < 0.05），在 18 天，2.75±0.05 log10 cfu，在 25 天，1.89±0.43 log10 cfu，与对照组相比，对照组鸡在 18 天的 SH 回收为 5.6±0.37（d 18）和 3.98±0.5 log10 cfu（d 25）。这些实验的结果表明，使用这些 SE 和 ST 载体亚单位疫苗可以实现交叉血清群保护。
