Institute for Hygiene and National Consulting Laboratory for Hemolytic Uremic Syndrome (HUS), University of Münster, D-48149, Münster, Germany.
Sars International Centre for Marine Molecular Biology, University of Bergen, 5008, Bergen, Norway.
Sci Rep. 2020 Mar 18;10(1):4945. doi: 10.1038/s41598-020-59694-w.
The cardinal virulence factor of human-pathogenic enterohaemorrhagic Escherichia coli (EHEC) is Shiga toxin (Stx), which causes severe extraintestinal complications including kidney failure by damaging renal endothelial cells. In EHEC pathogenesis, the disturbance of the kidney epithelium by Stx becomes increasingly recognised, but how this exactly occurs is unknown. To explore this molecularly, we investigated the Stx receptor content and transcriptomic profile of two human renal epithelial cell lines: highly Stx-sensitive ACHN cells and largely Stx-insensitive Caki-2 cells. Though both lines exhibited the Stx receptor globotriaosylceramide, RNAseq revealed strikingly different transcriptomic responses to an Stx challenge. Using RNAi to silence factors involved in ACHN cells' Stx response, the greatest protection occurred when silencing RAB5A and TRAPPC6B, two host factors that we newly link to Stx trafficking. Silencing these factors alongside YKT6 fully prevented the cytotoxic Stx effect. Overall, our approach reveals novel subcellular targets for potential therapies against Stx-mediated kidney failure.
产志贺毒素（Stx）是人致病性肠出血性大肠杆菌（EHEC）的主要毒力因子，它通过破坏肾内皮细胞导致肾衰竭，引起严重的肠道外并发症。在 EHEC 发病机制中，Stx 对肾脏上皮细胞的干扰作用越来越受到重视，但具体如何发生尚不清楚。为了从分子水平上进行探讨，我们研究了两种人肾上皮细胞系：对 Stx 高度敏感的 ACHN 细胞和对 Stx 基本不敏感的 Caki-2 细胞的 Stx 受体含量和转录组谱。尽管这两种细胞系都表达 Stx 受体神经节苷脂，但 RNAseq 揭示了它们对 Stx 攻击的转录组反应存在显著差异。使用 RNAi 沉默与 ACHN 细胞 Stx 反应相关的因子，沉默 RAB5A 和 TRAPPC6B 这两种我们新发现与 Stx 转运有关的宿主因子，可产生最大的保护作用。与 YKT6 一起沉默这些因子可完全阻止细胞毒性 Stx 的作用。总的来说，我们的方法揭示了针对 Stx 介导的肾衰竭的潜在治疗的新的亚细胞靶标。
