State Key Laboratory of Sheep Genetic Improvement and Healthy Production/Institute of Animal Husbandry and Veterinary Medicine, Xinjiang Academy of Agricultural and Reclamation Sciences, 832000, Shihezi, China.
College of Animal Science and Technology, Shihezi University, Shihezi, 832000, China.
Parasit Vectors. 2021 Sep 23;14(1):489. doi: 10.1186/s13071-021-05001-z.
Cystic echinococcosis (CE) is a serious parasitic zoonosis caused by the larvae of the tapeworm Echinococcus granulosus. The development of an effective vaccine is one of the most promising strategies for controlling CE.
The E. granulosus 3-hydroxyacyl-CoA dehydrogenase (EgHCDH) gene was cloned and expressed in Escherichia coli. The distribution of EgHCDH in protoscoleces (PSCs) and adult worms was analyzed using immunofluorescence. The transcript levels of EgHCDH in PSCs and adult worms were analyzed using quantitative real-time reverse transcription PCR (RT-qPCR). The immune protective effects of the rEgHCDH were evaluated.
The 924-bp open reading frame sequence of EgHCDH, which encodes a protein of approximately 34 kDa, was obtained. RT-qPCR analysis revealed that EgHCDH was expressed in both the PSCs and adult worms of E. granulosus. Immunofluorescence analysis showed that EgHCDH was mainly localized in the tegument of PSCs and adult worms. Western blot analysis showed that the recombinant protein was recognized by E. granulosus-infected dog sera. Animal challenge experiments demonstrated that dogs immunized with recombinant (r)EgHCDH had significantly higher serum IgG, interferon gamma and interleukin-4 concentrations than the phosphate-buffered saline (PBS) control group. The rEgHCDH vaccine was able to significantly reduce the number of E. granulosus and inhibit the segmental development of E. granulosus compared to the PBS control group.
The results suggest that rEgHCDH can induce partial immune protection against infection with E. granulosus and could be an effective candidate for the development of new vaccines.
囊型包虫病（CE）是一种由绦虫细粒棘球蚴幼虫引起的严重寄生虫 zoonosis。开发有效的疫苗是控制 CE 的最有前途的策略之一。
克隆并在大肠杆菌中表达了细粒棘球蚴 3-羟酰基辅酶 A 脱氢酶（EgHCDH）基因。使用免疫荧光法分析了 EgHCDH 在原头蚴（PSCs）和成虫中的分布。使用定量实时 RT-PCR（RT-qPCR）分析了 PSCs 和成虫中 EgHCDH 的转录水平。评估了 rEgHCDH 的免疫保护作用。
获得了编码约 34 kDa 蛋白质的 924 bp 开放阅读框序列 EgHCDH。RT-qPCR 分析显示 EgHCDH 在细粒棘球蚴的 PSCs 和成虫中均有表达。免疫荧光分析显示 EgHCDH 主要定位于 PSCs 和成虫的表皮。Western blot 分析表明重组蛋白被感染细粒棘球蚴的狗血清识别。动物攻毒实验表明，用重组（r）EgHCDH 免疫的狗血清 IgG、干扰素γ和白细胞介素 4 浓度明显高于磷酸盐缓冲盐水（PBS）对照组。与 PBS 对照组相比，rEgHCDH 疫苗能够显著减少细粒棘球蚴的数量并抑制细粒棘球蚴的节段发育。
结果表明 rEgHCDH 可以诱导对细粒棘球蚴感染的部分免疫保护，可能是开发新疫苗的有效候选物。
