Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang Province, China; College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province, China.
Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang Province, China.
Microb Pathog. 2018 May;118:1-8. doi: 10.1016/j.micpath.2018.03.010. Epub 2018 Mar 7.
We previously developed a stable and marker-free Lactobacillus casei strain (PPαT Δupp) that contained a chromosomally integrated expression cassette (PPαT) that enabled the surface expression of the Clostridium perfringens alpha toxin. To measure immune responses against the alpha toxin, specific-pathogen-free BALB/c mice were inoculated with L. casei PPαT Δupp by oral gavage. Then, specific immunoglobulin A (IgA) and immunoglobulin G (IgG) antibodies and cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and flow cytometry (FCM). The results showed that alpha toxin-specific IgA and IgG antibodies and cytokines were markedly increased following immunization. Natural alpha toxin challenge and neutralization tests were performed. The results showed that immunized mice can fully resist 1.5 minimum lethal doses of toxin. These results indicated that the immunized mice can produce not only humoral immunity, but also cellular immunity. These results provide a new pathway for the development of a safe, effective, and food-grade vaccine.
我们之前开发了一种稳定且无标记的干酪乳杆菌菌株（PPαTΔupp），该菌株含有整合在染色体上的表达盒（PPαT），可使产气荚膜梭菌α毒素在表面表达。为了测量针对α毒素的免疫反应，用经口灌胃的方式将无特定病原体 BALB/c 小鼠接种 L. casei PPαTΔupp。然后，通过酶联免疫吸附试验（ELISA）和流式细胞术（FCM）测量特异性免疫球蛋白 A（IgA）和免疫球蛋白 G（IgG）抗体和细胞因子。结果表明，免疫后α毒素特异性 IgA 和 IgG 抗体和细胞因子明显增加。进行了天然α毒素的挑战和中和试验。结果表明，免疫的小鼠可以完全抵抗 1.5 个最小致死剂量的毒素。这些结果表明，免疫的小鼠不仅可以产生体液免疫，还可以产生细胞免疫。这些结果为开发安全、有效且食品级疫苗提供了新途径。
