State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, China.
PLoS Negl Trop Dis. 2023 Jun 8;17(6):e0011323. doi: 10.1371/journal.pntd.0011323. eCollection 2023 Jun.
Trichinella spiralis (T. spiralis) adult-specific deoxyribonuclease II-7 (TsDNase II-7), a member of the DNase II-like nuclease family with no DNase II activity, was identified in the excretory-secretory (ES) products of adult worms (AWs). However, its biological functions are still unclear. Our previous study revealed that TsDNase II-7 is located around the infection site in the intestinal tissue, speculating that it was involved in the T. spiralis invasion of host intestinal epithelial cells (IECs). This study aimed to use RNA interference to verify our speculation that TsDNase II-7 in 3-day old adult T. spiralis (Ad3) plays a role in intestinal invasion. TsDNase II-7-specific small interfering RNAs (siRNAs) were delivered into muscle larvae (MLs) to knockdown TsDNase II-7 expression by electroporation. Twenty-four hours later, the MLs transfected with 2 μM siRNA-841 exhibited decreased in TsDNase II-7 transcription and expression as compared to the control MLs. The knockdown of TsDNase II-7 expression did not affect ML viability, and the low expression of TsDNase II-7 still maintained in Ad3 recovered from TsDNase II-7-RNAi-ML infected mice, resulting in a weakened ability of Ad3 to invade intestinal epithelial cells (IECs). These results indicated that knockdown of TsDNase II-7 gene expression via RNA interference (RNAi) suppressed adult worm invasion and confirmed that TsDNase II-7 plays a crucial role during the intestinal phase of T. spiralis infections, which provided new candidate for vaccine development of T. spiralis.
旋毛虫（T. spiralis）成虫特异性脱氧核糖核酸酶 II-7（TsDNase II-7）是一种无脱氧核糖核酸酶 II 活性的脱氧核糖核酸酶 II 样核酸酶家族成员，在成虫（AWs）的排泄-分泌（ES）产物中被鉴定出来。然而，其生物学功能尚不清楚。我们之前的研究表明，TsDNase II-7 位于肠道组织中的感染部位周围，推测它参与了旋毛虫对宿主肠上皮细胞（IECs）的侵袭。本研究旨在利用 RNA 干扰来验证我们的推测，即 3 日龄旋毛虫（Ad3）中的 TsDNase II-7 在肠道侵袭中发挥作用。通过电穿孔将 TsDNase II-7 特异性小干扰 RNA（siRNA）递送至肌肉幼虫（MLs）中，以敲低 TsDNase II-7 的表达。24 小时后，与对照 MLs 相比，转染 2 μM siRNA-841 的 MLs 中 TsDNase II-7 的转录和表达水平降低。敲低 TsDNase II-7 的表达并不影响 ML 的活力，并且从 TsDNase II-7-RNAi-ML 感染的小鼠中恢复的 Ad3 仍然保持低表达的 TsDNase II-7，导致 Ad3 侵袭肠上皮细胞（IECs）的能力减弱。这些结果表明，通过 RNA 干扰（RNAi）敲低 TsDNase II-7 基因表达抑制了成虫的侵袭，并证实 TsDNase II-7 在旋毛虫感染的肠道阶段发挥关键作用，为旋毛虫疫苗的开发提供了新的候选靶点。
