Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, 602 Tower Rd., Ithaca, NY, 14853, United States.
Department of Microbiology, Immunology, and Biopharmaceuticals, College of Life Sciences, National Chiayi University, No. 300, University Rd., Chiayi, 60004, Taiwan, ROC.
Comp Immunol Microbiol Infect Dis. 2019 Aug;65:41-47. doi: 10.1016/j.cimid.2019.04.003. Epub 2019 Apr 16.
S. Choleraesuis (Choleraesuis) and S. Typhimurium (Typhimurium) cause salmonellosis in pigs and humans. The effects of vaccine strains pSV-less Typhimurium OU5048 and Choleraesuis OU7266 and SPI-2-mutant Choleraesuis SC2284 on the immune responses of pigs against Typhimurium, Choleraesuis, and S. Enteritidis (Enteritidis) with or without the virulence plasmid (pSV) were determined. After oral vaccination of three vaccine groups and challenge with Choleraesuis CN36, the level of Salmonella-specific IgG in sera and the bactericidal effects and superoxide generation of peripheral blood mononuclear cells (PBMCs) and polymorphonuclear leukocytes (PMNs) against the above strains were determined using ELISA and NBT assay, respectively. Among three vaccine strains tested, OU7266 stimulated the highest Salmonella-specific IgG levels. Complement inactivation increased IgG concentration, while E. coli absorption reduced IgG levels. The pSV-containing strains were less resistant to serum killing than the pSV-less strains, and Enteritidis exhibited the lowest resistance to serum killing. Serovars tested, vaccine strains, and timeline periods postvaccination and challenge were important factors affecting superoxide production. The two Choleraesuis vaccine strains stimulated greater levels of superoxide from PMNs and PBMCs than the Typhimurium strains. The PMNs and PBMCs in challenged and vaccinated pigs reduced more superoxide than those in challenged hosts. In vaccinated hosts, pSV-less Salmonella strains triggered lower levels of PMN/PBMC-generated superoxide upon challenge than strains with pSV against Enteritidis and Choleraesuis. Overall, Choleraesuis OU7266 may be better than the other vaccine strains in generating the greatest IgG levels, serum bactericidal activity and superoxide levels. The pSV likely influences the immune responses.
猪霍乱沙门氏菌（Choleraesuis）和鼠伤寒沙门氏菌（Typhimurium）可引起猪和人类的沙门氏菌病。本研究旨在评估减毒鼠伤寒沙门氏菌 pSV-less OU5048 和猪霍乱沙门氏菌 OU7266 疫苗株以及 SPI-2 突变株猪霍乱沙门氏菌 SC2284 对猪针对鼠伤寒沙门氏菌、猪霍乱沙门氏菌和肠炎沙门氏菌（Enteritidis）的免疫反应的影响，同时评估有无毒力质粒（pSV）的影响。通过口服免疫三组疫苗，然后用猪霍乱沙门氏菌 CN36 攻毒，用 ELISA 和 NBT 试验分别检测血清中沙门氏菌特异性 IgG 水平以及外周血单核细胞（PBMCs）和多形核白细胞（PMNs）对上述菌株的杀菌作用和超氧化物生成。在测试的三种疫苗株中，OU7266 刺激产生的沙门氏菌特异性 IgG 水平最高。补体失活增加 IgG 浓度，而大肠杆菌吸收降低 IgG 水平。含 pSV 的菌株比无 pSV 的菌株对血清杀伤的抵抗力低，肠炎沙门氏菌对血清杀伤的抵抗力最低。所测试的血清型、疫苗株、攻毒和接种后的时间周期是影响超氧化物生成的重要因素。两种猪霍乱沙门氏菌疫苗株刺激 PMNs 和 PBMC 产生的超氧化物水平高于鼠伤寒沙门氏菌菌株。攻毒和接种猪的 PMNs 和 PBMC 产生的超氧化物比攻毒宿主中的 PMNs 和 PBMC 少。在接种宿主中，与具有 pSV 的菌株相比，无 pSV 的沙门氏菌菌株在攻毒时引发的 PMN/PBMC 产生的超氧化物水平较低，针对肠炎沙门氏菌和猪霍乱沙门氏菌。总的来说，猪霍乱沙门氏菌 OU7266 可能比其他疫苗株更能产生最大的 IgG 水平、血清杀菌活性和超氧化物水平。pSV 可能影响免疫反应。
