Rosas G, Cruz-Revilla C, Fragoso G, López-Casillas F, Pérez A, Bonilla M A, Rosales R, Sciutto E
Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, DF, México.
J Parasitol. 1998 Jun;84(3):516-23.
The purpose of this study was to evaluate DNA vaccination in cysticercosis prevention by using a Taenia crassiceps cDNA of a recombinant antigen (KETc7) that has been reported as protective against murine cysticercosis. The KETc7 cDNA was cloned into the pcDNA3 plasmid alone or with the betaglycan signal peptide sequence (pTc-7 and pTc-sp7, respectively). Positive expression of the pTc-sp7 product was confirmed by transfection of C33 cells and immunofluorescence using sera of mice infected with T. crassiceps. Immunization of mice with 3 injections of pTc-sp7 DNA at the higher dose (200 microg) was the most effective to induce antibody with or without bupivacaine. Immunization with pTc-sp7 induced protection against challenge with T. crassiceps cysticerci as successfully as previously observed with the KETc7 recombinant protein. Antibodies elicited by DNA immunization with pTc-sp7 specifically reacted with the native protein of 56 kDa previously reported, which is immunolocalized in the tegument of T. crassiceps cysticerci. The 56-kDa antigen is also present in Taenia solium oncospheres, cysticerci, and adult tissue. The protection induced in DNA-immunized mice and the observation that the injected plasmid remains as an episomic form within muscle cells, encouraged us to continue testing this procedure to prevent T. solium cysticercosis.
本研究的目的是通过使用已报道对鼠囊尾蚴病具有保护作用的重组抗原（KETc7）的肥胖带绦虫cDNA来评估DNA疫苗在预防囊尾蚴病中的作用。将KETc7 cDNA单独或与β聚糖信号肽序列（分别为pTc-7和pTc-sp7）克隆到pcDNA3质粒中。通过转染C33细胞并用感染肥胖带绦虫的小鼠血清进行免疫荧光检测，证实了pTc-sp7产物的阳性表达。用较高剂量（200微克）的pTc-sp7 DNA对小鼠进行3次注射免疫，无论有无布比卡因，诱导抗体的效果最为显著。用pTc-sp7免疫诱导的对肥胖带绦虫囊尾蚴攻击的保护作用，与先前观察到的KETc7重组蛋白的效果一样成功。用pTc-sp7进行DNA免疫引发的抗体与先前报道的56 kDa天然蛋白特异性反应，该蛋白免疫定位在肥胖带绦虫囊尾蚴的皮层中。56 kDa抗原也存在于猪带绦虫六钩蚴、囊尾蚴和成虫组织中。DNA免疫小鼠诱导的保护作用以及注射的质粒在肌肉细胞内以附加体形式存在的观察结果，促使我们继续测试该方法以预防猪带绦虫囊尾蚴病。
