Institute of Veterinary Anatomy, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
Department of Animal Sciences, North Dakota State University, Fargo, ND, USA.
Toxicol In Vitro. 2019 Oct;60:437-449. doi: 10.1016/j.tiv.2019.05.017. Epub 2019 May 30.
Gram-negative bacteria, in particular Escherichia coli with its cell wall lipopolysaccharide (LPS), often cause metritis and mastitis in domestic animals. Ovarian LPS accumulation may initiate local inflammatory reactions mediated through cell surface Toll-like receptors (TLRs). This may disrupt ovarian functionality leading to infertility. Possible adverse effects of LPS on luteal activity are not yet well explored. We hypothesized that LPS could lead to alterations in luteal vascular functionality. Therefore, we established an in vitro cell line model (OLENDO) by immortalizing microvascular endothelial cells isolated from ovine corpus luteum (CL) with a potent Simian Virus 40 T-antigen (SV40-Tag). OLENDO exhibit endothelial cell characteristics, like low-density lipoprotein (LDL) uptake, express BSL-I, and VEGFR2, as well as TLR2 and TLR4 receptors. LPS-treatment of OLENDO altered in vitro tube formation, had no effects on cell viability and decreased gap junctional intercellular communication (GJIC). LPS did not impair GJA1/Cx43 protein expression, but altered its cellular localization showing signs of internalization. Taken together, we demonstrated the mechanisms underlying LPS induced impairment of luteal GJIC and immune processes in a novel and well-characterized OLENDO cell line.
革兰氏阴性菌，特别是具有细胞壁脂多糖（LPS）的大肠杆菌，常引起家畜的子宫内膜炎和乳腺炎。卵巢中 LPS 的积累可能通过细胞表面 Toll 样受体（TLR）引发局部炎症反应。这可能破坏卵巢功能，导致不孕。LPS 对黄体活性的可能不良影响尚未得到充分探索。我们假设 LPS 可能导致黄体血管功能发生变化。因此，我们通过用强效猴病毒 40 大 T 抗原（SV40-Tag）永生化从羊黄体（CL）分离的微血管内皮细胞，建立了体外细胞系模型（OLENDO）。OLENDO 表现出内皮细胞的特征，如 LDL 摄取、表达 BSL-I 和 VEGFR2 ，以及 TLR2 和 TLR4 受体。LPS 处理 OLENDO 改变了体外管形成，对细胞活力没有影响，并降低了缝隙连接细胞间通讯（GJIC）。LPS 没有损害 GJA1/Cx43 蛋白的表达，但改变了其细胞定位，显示出内化的迹象。总之，我们在一种新型且特征明确的 OLENDO 细胞系中证明了 LPS 诱导黄体 GJIC 和免疫过程损伤的机制。
