Yang Yi, Chen Jianlin, Li Hui, Wang Yingyi, Xie Zhao, Wu Mei, Zhang Huan, Zhao Zhongzhong, Chen Qian, Fu Manliang, Wu Kaiyuan, Chi Cheng, Wang Hongning, Gao Rong
Key Lab for Bio-Resource and Eco-Environment of Education Ministry, Bioengineering Research Center for Animal Disease Prevention and Control, Life Science College, Sichuan University, Wangjiang Road No. 29, Chengdu 610064, China.
Comp Immunol Microbiol Infect Dis. 2007 Jan;30(1):19-32. doi: 10.1016/j.cimid.2006.09.006. Epub 2006 Oct 10.
Interleukin-2 (IL-2) is vital to elicit and amplify the cellular and humoral immune responses to foreign antigens, which is extensively utilized in the control of infectious disease and treatment of various cancers. Porcine and murine IL-2 genes were, respectively, subcloned into VR1020, designated as VPIL-2 and VMIL-2, and then encapsulated in chitosan nanoparticles (CNP) prepared by ionic linkage. The BALB/c mice were intramuscularly co-administrated with chitosan-IL-2 nanoparticles (CNP-IL2) and paratyphoid vaccine to test the adjuvant effect of CNP-IL2. On day 35, the immunized mice were orally challenged with virulent Salmonella. The content of IgG, IgA, IgM, IL-2, IL-4, IL-6 and specific antibody titer as well as the number of immunocompetent cells were systematically analyzed in the vaccinated mice. The results revealed that the levels of immunoglobulins, cytokines, the specific antibodies, together with the numbers of lymphocytes significantly increased in vaccinated mice inoculated with CNP-VPIL2 in contrast with those with naked IL-2 plasmids and blank plasmids. The CNP-VPIL2 immunized mice exhibited higher humoral and cellular immune responses, less severe clinical signs and lesions of disease caused by the bacteria than the other groups after challenge. These findings suggest that CNP-VPIL2 has a significant enhancement effect on immune responses of mice, which results in better immunoprotection against Salmonella infection, indicating that CNP-VPIL2 could be employed as an effective immunoadjuvant to elevate immunity of animals to conventional vaccines.
白细胞介素-2（IL-2）对于引发和增强针对外来抗原的细胞免疫和体液免疫反应至关重要，其在传染病控制和各种癌症治疗中得到广泛应用。分别将猪和鼠的IL-2基因亚克隆到VR1020中，命名为VPIL-2和VMIL-2，然后包封于通过离子键制备的壳聚糖纳米颗粒（CNP）中。将壳聚糖-IL-2纳米颗粒（CNP-IL2）与副伤寒疫苗联合肌肉注射给BALB/c小鼠，以测试CNP-IL2的佐剂效果。在第35天，对免疫小鼠口服强毒力沙门氏菌进行攻毒。系统分析了接种疫苗小鼠体内IgG、IgA、IgM、IL-2、IL-4、IL-6的含量、特异性抗体滴度以及免疫活性细胞数量。结果显示，与接种裸IL-2质粒和空白质粒的小鼠相比，接种CNP-VPIL2的小鼠体内免疫球蛋白、细胞因子、特异性抗体水平以及淋巴细胞数量显著增加。攻毒后，与其他组相比，CNP-VPIL2免疫的小鼠表现出更高的体液免疫和细胞免疫反应，临床症状和细菌引起的疾病病变较轻。这些发现表明，CNP-VPIL2对小鼠的免疫反应具有显著增强作用，能更好地抵抗沙门氏菌感染，表明CNP-VPIL2可作为一种有效的免疫佐剂来提高动物对传统疫苗的免疫力。
