Key Laboratory for Animal Genetics, Breeding, Reproduction and Molecular Design of Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu 225009, China.
Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou, Jiangsu, 225009, China.
Pol J Vet Sci. 2020 Mar;23(1):119-126. doi: 10.24425/pjvs.2020.132755.
To explore the role of Toll-like receptors (TLRs) and interferon (IFN) in the innate immunity against porcine epidemic diarrhea virus (PEDV), we detected the expression of TLR genes in PEDV-infected IPEC-J2 cells by real-time PCR. We also detected the level of interferon α (IFN-α) and interferon γ (IFN-γ) by enzyme-linked immunosorbent assay (ELISA). Results showed that IPEC-J2 cells exhibited a clear pathological change after PEDV infection at 24 h. In addition, TLR7, TLR9 and TLR10 expressions were significantly upregulated in PEDV-infected IPEC-J2 cells at 24 h. Interestingly, the expression patterns of TLR2 and TLR4 were consistent at different stages of PEDV infection. The expression level of TLR3 decreased significantly with the increase of infection time, but the expression levels of TLR5 and TLR8 genes at 6 h and 12 h were significantly lower than those in the control group (p⟨0.01). There were significant correlations among the expression levels of TLR genes (p⟨0.05). Cytokine detection showed that the secretion level of IFN-α in the PEDV-infected group was significantly higher than that in the control group (p⟨0.01), and IFN-γ at 6 h and 12 h after PEDV infection was significantly higher than that in control group (p⟨0.01). Therefore, our results suggest that PEDV infection can induce innate immune responses in intestinal porcine jejunum epithelial cells, leading to changes in the expression of Toll-like receptors, and can regulate the resistance to virus infection by affecting the release levels of downstream cytokines.
为了探索 Toll 样受体（TLRs）和干扰素（IFN）在猪流行性腹泻病毒（PEDV）固有免疫中的作用，我们通过实时 PCR 检测了 PEDV 感染的 IPEC-J2 细胞中 TLR 基因的表达。我们还通过酶联免疫吸附试验（ELISA）检测了干扰素α（IFN-α）和干扰素γ（IFN-γ）的水平。结果显示，PEDV 感染后 24 h，IPEC-J2 细胞出现明显的病理变化。此外，在 PEDV 感染的 IPEC-J2 细胞中，TLR7、TLR9 和 TLR10 的表达在 24 h 时显著上调。有趣的是，TLR2 和 TLR4 的表达模式在 PEDV 感染的不同阶段是一致的。TLR3 的表达水平随着感染时间的增加而显著下降，但 TLR5 和 TLR8 基因在 6 h 和 12 h 的表达水平明显低于对照组（p⟨0.01）。TLR 基因的表达水平之间存在显著相关性（p⟨0.05）。细胞因子检测显示，PEDV 感染组 IFN-α 的分泌水平明显高于对照组（p⟨0.01），PEDV 感染后 6 h 和 12 h IFN-γ 的水平明显高于对照组（p⟨0.01）。因此，我们的结果表明，PEDV 感染可诱导肠猪空肠上皮细胞固有免疫反应，导致 Toll 样受体表达发生变化，并通过影响下游细胞因子的释放水平来调节对病毒感染的抵抗力。
