Ahmadpour Ehsan, Sarvi Shahabeddin, Hashemi Soteh Mohammad Bagher, Sharif Mehdi, Rahimi Mohammad Taghi, Valadan Reza, Tehrani Mohsen, Khalilian Alireza, Montazeri Mahbobeh, Fasihi-Ramandi Mahdi, Daryani Ahmad
Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
Immunol Lett. 2017 May;185:40-47. doi: 10.1016/j.imlet.2017.03.006. Epub 2017 Mar 9.
Several approaches have been used to improve the immunogenicity of DNA vaccines. In the current study, we constructed the plasmid encoding T. gondii dense granule 14 (GRA14) and investigated the immunological properties of calcium phosphate nanoparticles (CaPNs) as nano-adjuvant to enhance the protective efficacy of pcGRA14. BALB/c mice intramuscularly injected three times at two-week intervals and the immune responses were evaluated using lymphocyte proliferation assay, cytokine and antibody measurements, survival times, and parasite load of mice challenged with the virulent T. gondii RH strain. The results showed that the immune responses were induced in mice receiving pcGRA14 DNA vaccine. Interestingly, pcGRA14 coated with nanoparticles led to statistically significant enhancements of cellular and humoral immune responses against Toxoplasma infection (P<0.05). After challenge with RH strain of T. gondii, immunized mice with pcGRA14 showed prolong survival time compared to control groups (P<0.05). In addition, pcGRA14 coated with nano-adjuvant exhibited the lowest parasitic load in the infected mice tissues. For the first time, our data indicate that the pcGRA14 coated with CaPN was more effective for stimulation of immune responses and should be considered as an adjuvant in the design of vaccines against toxoplasmosis.
已经采用了几种方法来提高DNA疫苗的免疫原性。在本研究中，我们构建了编码弓形虫致密颗粒蛋白14（GRA14）的质粒，并研究了磷酸钙纳米颗粒（CaPNs）作为纳米佐剂增强pcGRA14保护效力的免疫学特性。以两周的间隔对BALB/c小鼠进行三次肌肉注射，并使用淋巴细胞增殖试验、细胞因子和抗体检测、存活时间以及用强毒株弓形虫RH株攻击的小鼠的寄生虫载量来评估免疫反应。结果表明，接受pcGRA14 DNA疫苗的小鼠诱导了免疫反应。有趣的是，用纳米颗粒包被的pcGRA14导致针对弓形虫感染的细胞免疫和体液免疫反应在统计学上有显著增强（P<0.05）。在用弓形虫RH株攻击后，与对照组相比，用pcGRA14免疫的小鼠存活时间延长（P<0.05）。此外，用纳米佐剂包被的pcGRA14在感染小鼠组织中的寄生虫载量最低。我们的数据首次表明，用CaPN包被的pcGRA14在刺激免疫反应方面更有效，应被视为抗弓形虫病疫苗设计中的一种佐剂。
