The effects of salt on the physicochemical properties and immunogenicity of protein based vaccine formulated in cationic liposome.
The effects of salt on the physicochemical properties and immunogenicity of protein based vaccine formulated in cationic liposome.
复制标题
盐对阳离子脂质体中配制的蛋白质疫苗的理化性质和免疫原性的影响。
DOI：
10.1016/j.ijpharm.2008.09.053
复制
发表时间：
2009
影响因子：
5.8
通讯作者：
Huang,Leaf
中科院分区：
文献类型：
--
作者：
Yan,Weili;Huang,Leaf
最近，我们开发了一种简单而有效的治疗性癌症疫苗，它由阳离子脂和多肽抗原组成。在这份报告中，我们将这种配方的用途扩展到基于蛋白质的疫苗。首先，我们在不同剂量的DOTAP脂质体中制备了人乳头瘤病毒(HPV)16E7蛋白(E7)。结果表明，这些制剂未能使已建立的肿瘤消退。然而，当在DOTAP(100nmol)/E7(20μg)制剂中加入30 mM的氯化钠时，免疫小鼠产生了抗肿瘤活性。相应地，在DOTAP/E7蛋白配方中加入30 mMNaC l使∼颗粒尺寸从Zeta350增加到550 nm，蛋白质负载量从95%降低到90%，最终增加了Zeta电位(从29 mV增加到38 mV)。其次，将模型蛋白抗原卵清蛋白(OVA)与不同剂量的DOTAP脂质体配伍。同样，在200nmolDOTAP和30mMNaC l中配制的20μg卵清蛋白具有最好的卵清蛋白特异性抗体应答，包括IgG1和IgG2a，表明该制剂既能产生Th1免疫应答，又能产生Th2型免疫应答。综上所述，我们扩大了阳离子DOTAP脂质体制剂在蛋白质疫苗中的应用，并发现少量的盐可以改变疫苗制剂的物理化学性质，提高DOTAP/蛋白质疫苗的活性。盐对免疫应答的增强作用可能是由于其干扰了阳离子脂类与蛋白质抗原之间的静电相互作用，促进了抗原从载体上的释放，同时激活了抗原提呈细胞。
Recently, we have developed a simple and potent therapeutic cancer vaccine consisting of a cationic lipid and a peptide antigen. In this report, we expanded the utility of this formulation to protein based vaccines. First, we formulated the human papillomavirus (HPV) 16 E7 protein (E7) in different doses of DOTAP liposome. The results showed that these formulations failed to regress an established tumor. However, when sodium chloride (30mM) was added to the DOTAP (100nmol)/E7 (20μg) formulation, anti-tumor activity was generated in the immunized mice. Correlatively, 30mM NaCl in the DOTAP/E7 protein formulation increased the particle size from ∼350 to 550nm, decreased the protein loading capacity (from 95 to 90%), and finally increased the zeta potential (from 29 to 38mV). Next, a model protein antigen ovalbumin (OVA) was formulated in different doses of DOTAP liposomes. Similarly, the results showed that 20μg OVA formulated in 200nmol DOTAP with 30mM NaCl had the best OVA-specific antibody response, including both IgG1and IgG2a, suggesting both Th1 and Th2 immune responses were generated by this formulation. In conclusion, we have expanded the application of cationic DOTAP liposome formulation to protein based vaccines and also identified that small amounts of salt could change the physicochemical properties of the vaccine formulation and enhance the activity of the DOTAP/protein based vaccine. The enhancement of immune responses by salt is possibly due to its interference of the electrostatic interaction between the cationic lipid and the protein antigen to facilitate the antigen release from the carrier and at the same time activate the antigen presenting cells.