Anti-TGEV Miller Strain Infection Effect of Lactobacillus plantarum Supernatant Based on the JAK-STAT1 Signaling Pathway

Wang, Kai; Ran, Ling; Yan, Tao; Niu, Zheng; Kan, Zifei; Zhang, Yiling; Yang, Yang; Xie, Luyi; Huang, Shilei; Yu, Qiuhan; Wu, Di; Song, Zhenhui

Previous studies have found that many lactic acid bacteria can inhibit the infection of diarrhea-causing viruses (such as RV and PEDV) in the host through a variety of methods (Hou et al., 2007; Kawakami et al., 2010) . Some lactic acid bacteria can be recognized by Toll like receptor (TLR)-2 or TLR-9 to enhance their response to stimulation by the interferon inducer poly (I: C) and induce a large amount of IFN-I (Maeda et al., 2009; Kanmani and Kim, 2018; Lee et al., 2019) . At the same time, they can also upregulate the transcription of IL6 and TNFA (Reyes-Diaz et al., 2018) . In addition, some lactic acid bacteria can enhance the expression of surface molecules and cytokines in intestinal (A-F) Relative mRNA expression levels of MX1, MX2, PKR, ZAP, ISG15, and OASL, respectively. The expression levels of ZAP, MX2, and MX1 in Lp-1s group after 12 h were not significantly different from those in the TGEV group (P > 0.05). The expression level of ISG15 was significantly higher in the Lp-1s group than in the TGEV group ( * P < 0.05). The expression levels of PKR and OASL were significantly higher in the Lp-1s group than in the TGEV group ( * * P < 0.01). The expression levels of ZAP, MX2, MX1, PKR, OASL, and ISG15 in the Lp-1s group after 24 and 48 h were significantly higher than (Continued) FIGURE 7 | Continued those in the TGEV group ( * * P < 0.01). (G,H) Screening of siRNA targeting STAT1 optimal treatment time and gene silencing efficiency fragment. As shown in the figure, the optimal time for siRNA targeting STAT1 is 48 h, and the best gene silencing siRNA fragment is siRNA1 ( * P < 0.05). (I-N) Relative mRNA expression levels of MX1, MX2, PKR, ZAP, ISG15, and OASL, respectively, after targeting gene silencing STAT1. The expression levels of PKR and OASL in Lp-1s group after 12 h were not significantly different from those in the TGEV group (P > 0.05). The expression level of MX2, PKR, ZAP, ISG15, and OASL was significantly higher in the Lp-1s group after 24 h than in the TGEV group ( * P < 0.05 and * * P < 0.01). The expression levels of ZAP, ISG15 and OASL were significantly higher in the Lp-1s group after 48 h than in the TGEV group ( * P < 0.05 and * * P < 0.01).