The Mechanism of Bacterial Endotoxin Invasion Pathways in Porcine Reproductive and Respiratory Syndrome Virus-Positive Porcine Endometrial Epithelial Cells.

Porcine reproductive and respiratory syndrome virus (PRRSV) causes abortions, stillbirths, and dummy pregnancies. Previous studies found that PRRSV can promote secondary bacterial infections and elevate bacterial endotoxin levels, further increasing the abortion rate in sows. However, the pathways by which bacterial endotoxins invade the bodies of PRRSV(+) sows and aggravate their clinical symptoms are unknown. In this study, we established a model of PRRSV and lipopolysaccharide (LPS) working together on porcine endometrial epithelial cells (PEECs). We speculate that PRRSV and LPS affect PEECs through viral protein interaction with cytokines and cytokine receptors, natural killer cell-mediated cytotoxicity, and regulation of actin cytoskeleton signaling pathways by analyzing seq-RNA. The PRRSV proteins act on inflammatory factors and their receptors to activate chemokines-5 (CCL5), chemokines-4 (CCL4), and chemokines-8 (CCL8) mRNA expression, causing severe inflammatory reactions. In addition, the elevation of MEK1/2 factors and the integrins acting on NK cells promote the upregulation of VAV1/Tiam1, RAC, and IRSp53, leading to increased expression of Arp2/3 and F-actin in PEECs in the PRRSV + LPS(+) groups. However, the highly expressed cell microfilaments and cytoskeleton disrupt the original network structure, causing changes in the original physiological function of the PEECs. In summary, the PRRSV protein interacts with cytokines and cytokine receptors of PEECs, thereby enhancing virus-mediated chemokine factors and their receptor activity, accelerating bacterial endotoxin entry into the body and the invasion of cells. They destroy the cytoskeletal structure of the cells and increase damage to uterine tissue. [ABSTRACT FROM AUTHOR]