College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China.
College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China.
Vet Parasitol. 2022 May;305:109710. doi: 10.1016/j.vetpar.2022.109710. Epub 2022 Apr 16.
Cryptosporidium spp. can cause diarrhea and even death in humans and animals. Host microRNAs (miRNAs) play an important role in the post-transcriptional regulation of the innate immune response to Cryptosporidium infection. To study host miRNA activity in the innate immune response to C. parvum infection, we examined the expression of miR-181d in HCT-8 cells infected with C. parvum and found that it was significantly downregulated, while TLR2, TLR4, NF-κB, and myD88 involved in the TLR/NF-κB signaling pathway were significantly upregulated at the early stages of C. parvum infection. We transfected cells with short-interfering RNAs (siRNA) as TLR2, TLR4, and NF-κB inhibitors. Analysis by quantitative real-time polymerase chain reaction (qPCR) and western blot confirmed that C. parvum downregulates miR-181d expression via the p50 subunit-dependent TLR2/TLR4-NF-κB signaling pathway in HCT-8 cells. This study provides a new theoretical foundation to elucidate the regulatory mechanism of host miRNAs against Cryptosporidium infection.
隐孢子虫属可引起人类和动物腹泻甚至死亡。宿主 microRNAs（miRNAs）在隐孢子虫感染的先天免疫反应的转录后调控中发挥重要作用。为了研究宿主 miRNA 在对微小隐孢子虫感染的先天免疫反应中的活性，我们检测了微小隐孢子虫感染的 HCT-8 细胞中 miR-181d 的表达，发现其显著下调，而 TLR2、TLR4、NF-κB 和 MyD88 参与 TLR/NF-κB 信号通路在微小隐孢子虫感染的早期阶段显著上调。我们用小干扰 RNA（siRNA）转染细胞作为 TLR2、TLR4 和 NF-κB 抑制剂。通过定量实时聚合酶链反应（qPCR）和 Western blot 分析证实，微小隐孢子虫通过 p50 亚基依赖性 TLR2/TLR4-NF-κB 信号通路下调 HCT-8 细胞中 miR-181d 的表达。本研究为阐明宿主 miRNAs 对抗隐孢子虫感染的调控机制提供了新的理论基础。
