Lincoln University, P.O. Box 84, Lincoln 7647, Canterbury, New Zealand.
Exp Parasitol. 2010 Apr;124(4):365-72. doi: 10.1016/j.exppara.2009.11.015. Epub 2009 Dec 3.
Immunization with plasmid DNA, a relatively novel technique, is a promising vaccination technique. To improve the immune response by DNA vaccination various methods have been used, such as chemical adjuvants or immunomodulatory molecules formulated into microparticles or liposomes. The aim of this research is to evaluate the immune responses of sheep immunized with DNA plasmids encoding Toxoplasma gondii dense granule antigen GRA7 formulated into three different adjuvant formulations. Sixty sheep were injected intramuscularly with the DNA plasmids. Twelve received the liposome-formulated plasmid pVAXIgGRA7, 12 Emulsigen P formulated plasmid pVAXIgGRA7 and 12 Emulsigen D formulated plasmid pVAXIgGRA7. Twelve animals were used as a control and received the vector alone. All the animals were inoculated at week 0, and week 4. Immunization of the sheep with plasmids encoding GRA7, with the different adjuvant formulations, effectively primed the immune response. After the first inoculation, moderate to high antibody responses were observed with the three different adjuvant formulations. A significantly elevated specific IgG2 response was observed in the sheep immunized with liposomes and Emulsigen D as adjuvants. In the group immunized with Emulsigen P as an adjuvant, lower IgG1 and IgG2 antibody levels were developed compared to the other treatment groups. In all the immunized groups, DNA immunization stimulated a IFN-gamma response. No antibody or IFN-gamma responses were detected in the control group immunized with an empty plasmid or not immunized. These results indicate that intramuscular immunization of sheep with a DNA vaccine with the adjuvants liposomes and Emulsigen D induce a significant immune response against T. gondii.
用质粒 DNA 进行免疫接种是一种相对较新的技术，是一种很有前途的疫苗接种技术。为了通过 DNA 疫苗接种提高免疫反应，已经使用了各种方法，例如将化学佐剂或免疫调节分子制成微球或脂质体。本研究的目的是评估用编码弓形虫致密颗粒抗原 GRA7 的 DNA 质粒免疫接种的绵羊的免疫反应，这些质粒被制成三种不同的佐剂制剂。将 60 只绵羊肌肉内注射 DNA 质粒。12 只接受脂质体配方的 pVAXIgGRA7，12 只接受 Emulsigen P 配方的 pVAXIgGRA7，12 只接受 Emulsigen D 配方的 pVAXIgGRA7。12 只动物作为对照，单独接受载体。所有动物均在第 0 周和第 4 周接种。用不同佐剂制剂编码 GRA7 的质粒对绵羊进行免疫接种，有效地启动了免疫反应。在第一次接种后，用三种不同的佐剂制剂观察到中等至高的抗体反应。用脂质体和 Emulsigen D 作为佐剂免疫接种的绵羊观察到特异性 IgG2 反应显著升高。用 Emulsigen P 作为佐剂免疫接种的组中，与其他治疗组相比，IgG1 和 IgG2 抗体水平较低。在所有免疫组中，DNA 免疫接种刺激了 IFN-γ 反应。在接受空质粒或未免疫接种的对照组中，未检测到抗体或 IFN-γ 反应。这些结果表明，用脂质体和 Emulsigen D 作为佐剂的 DNA 疫苗肌肉内免疫接种绵羊可诱导针对弓形虫的显著免疫反应。
