Department of Immunology, Cancer Institute and Cancer Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
Gene Ther. 2012 Dec;19(12):1187-95. doi: 10.1038/gt.2011.197. Epub 2011 Dec 15.
DNA vaccination is an attractive approach for eliciting antigen-specific immunity. In this study, we used magnetosomes (bacterial magnetic particles, BMPs) as carriers of a recombinant DNA composed of a secondary lymphoid tissue chemokine, human papillomavirus type E7 (HPV-E7) and Ig-Fc fragment (pSLC-E7-Fc) to generate a gene vaccine (BMP-V) for tumour immunotherapy. The results indicate that BMPs linked to DNA more efficiently in phosphate-buffered saline (pH=4-5) than in physiological saline. Efficient transfection of BMP-V in vitro and in vivo was achieved when a 600-mT static magnetic field was applied for 10 min. In a mouse tumour model, subcutaneous injection of BMP-V (5 μg, × 3 at 4-day intervals) plus magnetic exposure elicited systemic HPV-E7-specific immunity leading to significant tumour inhibition. The treated mice tolerated BMP-V immunisation well with no toxic side effects, as shown by histopathological examinations of major internal organs. Taken together, these results suggest that BMP can be used as a gene carrier to elicit a systemic immune response.
DNA 疫苗接种是一种有吸引力的方法，可以引起抗原特异性免疫。在这项研究中，我们使用磁铁矿（细菌磁性颗粒，BMP）作为由二次淋巴组织趋化因子、人乳头瘤病毒 E7 型（HPV-E7）和 Ig-Fc 片段（pSLC-E7-Fc）组成的重组 DNA 的载体，以产生用于肿瘤免疫治疗的基因疫苗（BMP-V）。结果表明，BMP 在 pH=4-5 的磷酸盐缓冲盐水（phosphate-buffered saline，PBS）中与 DNA 的结合效率高于生理盐水中的结合效率。当施加 600-mT 的静态磁场 10 分钟时，BMP-V 在体外和体内的有效转染得以实现。在小鼠肿瘤模型中，皮下注射 BMP-V（5μg，×3，间隔 4 天）加磁场暴露可引起全身 HPV-E7 特异性免疫，从而显著抑制肿瘤。如对主要内脏器官的组织病理学检查所示，接受 BMP-V 免疫接种的小鼠耐受良好，没有毒性副作用。总之，这些结果表明，BMP 可用作基因载体来引发全身免疫反应。
