Prophylactic therapy with human amniotic fluid stem cells improved survival in a rat model of lipopolysaccharide-induced neonatal sepsis through immunomodulation via aggregates with peritoneal macrophages
Prophylactic therapy with human amniotic fluid stem cells improved survival in a rat model of lipopolysaccharide-induced neonatal sepsis through immunomodulation via aggregates with peritoneal macrophages
复制标题
人羊水干细胞预防性治疗通过与腹腔巨噬细胞聚集的免疫调节改善脂多糖诱导的新生儿脓毒症大鼠模型的存活率
DOI：
10.1186/s13287-020-01809-1
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发表时间：
2020-07-20
影响因子：
7.5
通讯作者：
Tanaka, Mamoru
中科院分区：
文献类型：
--
作者：
Sato, Yu;Ochiai, Daigo;Tanaka, Mamoru
背景：尽管最近在新生儿护理方面取得了进展，但败血症仍然是新生儿死亡的主要原因。来自骨髓、脐带和脂肪组织等各种组织的间充质干细胞对成人脓毒症有有益作用。虽然人羊水干细胞（hAFSCs）具有间充质干细胞的特性，但hAFSCs对新生儿脓毒症的疗效尚不清楚。本研究旨在通过脂多糖（LPS）诱导的脓毒症大鼠模型，探讨hAFSCs对新生儿脓毒症的治疗潜力。方法从人羊水中分离cd117阳性细胞hAFSCs。3天大的大鼠幼崽腹腔注射LPS模拟新生儿脓毒症。在LPS暴露前3小时或暴露后0、3、24小时分别给予hAFSCs。分析血清炎症细胞因子水平、脾脏基因表达谱和多器官损伤情况。在体内确定hAFSC的定位。体外LPS刺激试验使用新生大鼠腹腔巨噬细胞与hAFSCs以细胞-细胞接触依赖/独立的方式共培养。使用DNA微阵列分析确定脾脏的免疫调节。结果hAFSCs预防性治疗可提高LPS治疗大鼠的存活率，而LPS暴露后hAFSCs移植未引起治疗反应。因此，所有后续研究均采用hAFSC预处理。LPS注射后炎性细胞因子水平升高，经hAFSC预处理后炎性细胞因子水平降低。随后，炎症引起的脑、肺和肝脏损伤得到改善。hAFSCs与腹膜巨噬细胞聚集和/或短暂地积聚在肝脏、肠系膜和腹膜。hAFSCs释放的旁分泌因子以细胞-细胞接触无关的方式诱导M1-M2巨噬细胞极化。hAFSCs与腹膜巨噬细胞的直接接触进一步增强了极化。脾脏微阵列分析显示，hAFSC预处理降低了凋亡和炎症相关基因的表达，从而抑制了toll样受体4信号通路。结论：在lps诱导的新生儿脓毒症大鼠模型中，hAFSCs预防性治疗可提高存活率。这些作用可能是由hAFSCs以细胞-细胞接触依赖/独立的方式触发的腹膜巨噬细胞从M1到M2的表型转换和随后的脾脏免疫调节介导的。
Background Despite recent advances in neonatal care, sepsis remains a leading cause of mortality in neonates. Mesenchymal stem cells derived from various tissues, such as bone marrow, umbilical cord, and adipose tissue, have beneficial effects on adult sepsis. Although human amniotic fluid stem cells (hAFSCs) have mesenchymal stem cell properties, the efficacy of hAFSCs on neonatal sepsis is yet to be elucidated. This study aimed to investigate the therapeutic potential of hAFSCs on neonatal sepsis using a rat model of lipopolysaccharide (LPS)-induced sepsis. Methods hAFSCs were isolated as CD117-positive cells from human amniotic fluid. Three-day-old rat pups were intraperitoneally treated with LPS to mimic neonatal sepsis. hAFSCs were administered either 3 h before or at 0, 3, or 24 h after LPS exposure. Serum inflammatory cytokine levels, gene expression profiles from spleens, and multiple organ damage were analyzed. hAFSC localization was determined in vivo. In vitro LPS stimulation tests were performed using neonatal rat peritoneal macrophages co-cultured with hAFSCs in a cell-cell contact-dependent/independent manner. Immunoregulation in the spleen was determined using a DNA microarray analysis. Results Prophylactic therapy with hAFSCs improved survival in the LPS-treated rats while the hAFSCs transplantation after LPS exposure did not elicit a therapeutic response. Therefore, hAFSC pretreatment was used for all subsequent studies. Inflammatory cytokine levels were elevated after LPS injection, which was attenuated by hAFSC pretreatment. Subsequently, inflammation-induced damages in the brain, lungs, and liver were ameliorated. hAFSCs aggregated with peritoneal macrophages and/or transiently accumulated in the liver, mesentery, and peritoneum. Paracrine factors released by hAFSCs induced M1-M2 macrophage polarization in a cell-cell contact-independent manner. Direct contact between hAFSCs and peritoneal macrophages further enhanced the polarization. Microarray analysis of the spleen showed that hAFSC pretreatment reduced the expression of genes involved in apoptosis and inflammation and subsequently suppressed toll-like receptor 4 signaling pathways. Conclusions Prophylactic therapy with hAFSCs improved survival in a rat model of LPS-induced neonatal sepsis. These effects might be mediated by a phenotypic switch from M1 to M2 in peritoneal macrophages, triggered by hAFSCs in a cell-cell contact-dependent/independent manner and the subsequent immunomodulation of the spleen.