Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, 25 Orde Street, Suite 6-1017, Toronto, ON M5G 1X5, Canada.
Department of Physiology, University of Toronto, Toronto, ON M5S 1A1, Canada.
Cells. 2021 Dec 31;11(1):128. doi: 10.3390/cells11010128.
Prophylactic administration of the broad-spectrum chemokine inhibitor (BSCI) FX125L has been shown to suppress uterine contraction, prevent preterm birth (PTB) induced by Group B Streptococcus in nonhuman primates, and inhibit uterine cytokine/chemokine expression in a murine model of bacterial endotoxin (LPS)-induced PTB. This study aimed to determine the mechanism(s) of BSCI action on human myometrial smooth muscle cells. We hypothesized that BSCI prevents infection-induced contraction of uterine myocytes by inhibiting the secretion of pro-inflammatory cytokines, the expression of contraction-associated proteins and disruption of myocyte interaction with tissue macrophages. Myometrial biopsies and peripheral blood were collected from women at term (not in labour) undergoing an elective caesarean section. Myocytes were isolated and treated with LPS with/out BSCI; conditioned media was collected; cytokine secretion was analyzed by ELISA; and protein expression was detected by immunoblotting and immunocytochemistry. Functional gap junction formation was assessed by parachute assay. Collagen lattices were used to examine myocyte contraction with/out blood-derived macrophages and BSCI. We found that BSCI inhibited (1) LPS-induced activation of transcription factor NF-kB; (2) secretion of chemokines (MCP-1/CCL2 and IL-8/CXCL8); (3) Connexin43-mediated intercellular connectivity, thereby preventing myocyte-macrophage crosstalk; and (4) myocyte contraction. BSCI represents novel therapeutics for prevention of inflammation-induced PTB in women.
广谱趋化因子抑制剂（BSCI）FX125L 的预防性给药已被证明可抑制子宫收缩，预防 B 族链球菌引起的早产（PTB），并抑制细菌内毒素（LPS）诱导的 PTB 小鼠模型中的子宫细胞因子/趋化因子表达。本研究旨在确定 BSCI 对人子宫平滑肌细胞作用的机制。我们假设 BSCI 通过抑制促炎细胞因子的分泌、收缩相关蛋白的表达以及破坏肌细胞与组织巨噬细胞的相互作用，防止感染引起的子宫肌细胞收缩。从足月（未分娩）行择期剖宫产的妇女中采集子宫活检和外周血。分离肌细胞并与 LPS 加/不加 BSCI 一起处理；收集条件培养基；通过 ELISA 分析细胞因子分泌；通过免疫印迹和免疫细胞化学检测蛋白表达。通过降落伞测定评估功能性缝隙连接形成。使用胶原格子检查有无血源性巨噬细胞和 BSCI 存在的肌细胞收缩。我们发现 BSCI 抑制了：（1）LPS 诱导的转录因子 NF-kB 激活；（2）趋化因子（MCP-1/CCL2 和 IL-8/CXCL8）的分泌；（3）Connexin43 介导的细胞间连接，从而防止肌细胞-巨噬细胞串扰；以及（4）肌细胞收缩。BSCI 为预防女性炎症诱导的 PTB 提供了新的治疗方法。
