The Institute of Veterinary Medicine, Xinjiang Academy of Animal Science, Urumqi 830000, China.
Vaccine. 2010 Mar 11;28(12):2408-15. doi: 10.1016/j.vaccine.2009.12.076. Epub 2010 Jan 9.
We investigated whether a combined DNA vaccine delivered together with the IL-15 gene (DNA-IL-15(+)) enhanced the immune response against Brucella abortus in mice. Mice vaccinated with DNA-IL-15(+) developed a robust humoral response; Brucella-specific antibodies exhibited a dominance of immunoglobulin G2a (IgG2a) over IgG1. Splenocytes from DNA-IL-15(+)-vaccinated mice induced significantly higher levels of IFN-gamma (P<0.01) and CD8(+) T cell response (P<0.01), suggesting induction of a T-helper-1-dominated immune response. In a specific cytotoxic-T-lymphocyte activity assay, DNA-IL-15(+) immunization elicited mainly CD8(+) T cells, which mediate cytotoxicity, but also CD4(+) T cells. In vivo depletion of T cell subsets showed that the DNA-IL-15(+)-induced protection against Brucella infection is mediated predominantly by CD8(+) T cells, although CD4(+) T cells also contribute. These data indicate that plasmid-delivered IL-15 increases the efficacy of the Brucella DNA vaccine.
我们研究了联合递送的 IL-15 基因的 DNA 疫苗（DNA-IL-15(+)）是否能增强小鼠对流产布鲁氏菌的免疫反应。用 DNA-IL-15(+)疫苗接种的小鼠产生了强大的体液反应；布鲁氏菌特异性抗体表现出 IgG2a（IgG2a）对 IgG1 的优势。来自 DNA-IL-15(+)疫苗接种小鼠的脾细胞诱导了显著更高水平的 IFN-γ（P<0.01）和 CD8(+) T 细胞反应（P<0.01），提示诱导了 Th1 优势的免疫反应。在特异性细胞毒性 T 淋巴细胞活性测定中，DNA-IL-15(+)免疫引发了主要介导细胞毒性的 CD8(+) T 细胞，但也引发了 CD4(+) T 细胞。体内耗尽 T 细胞亚群表明，针对布鲁氏菌感染的 DNA-IL-15(+)诱导的保护主要由 CD8(+) T 细胞介导，尽管 CD4(+) T 细胞也有贡献。这些数据表明，质粒递送的 IL-15 提高了布鲁氏菌 DNA 疫苗的功效。
