Jensen Amanda R, Manning Morenci M, Khaneki Sina, Drucker Natalie A, Markel Troy A
Department of Surgery, Section of Pediatric Surgery, Indianapolis, Indiana; Indiana University School of Medicine, Indianapolis, Indiana.
Department of Surgery, Section of Pediatric Surgery, Indianapolis, Indiana.
J Surg Res. 2016 Aug;204(2):361-370. doi: 10.1016/j.jss.2016.05.006. Epub 2016 May 11.
Transplantation of mesenchymal stromal cells (MSCs) may be a novel treatment for intestinal ischemia. The optimal stromal cell source that could yield maximal protection after injury, however, has not been identified. We hypothesized that (1) MSCs would increase survival and mesenteric perfusion, preserve intestinal histologic architecture, and limit inflammation after intestinal ischemia and reperfusion (I/R) injury, and (2) MSCs harvested from different sources of tissue would have equivalent protective properties to the intestine after I/R inury.
Adult male mice were anesthetized, and a midline laparotomy was performed. The intestines were eviscerated, the small bowel mesenteric root was identified, and baseline intestinal perfusion was determined using laser Doppler imaging. Intestinal ischemia was established by temporarily occluding the superior mesenteric artery for 60 min with a noncrushing clamp. After ischemia, the clamp was removed and the intestines were allowed to recover. Before abdominal closure, 2 × 10(6) human umbilical cord-derived MSCs, bone marrow-derived MSCs, or keratinocytes in 250 μL of phosphate-buffered saline vehicle were injected into the peritoneum. Animals were allowed to recover for 12 or 24 h (perfusion, histology, and inflammatory studies) or 7 d (survival studies). Survival data was analyzed using the log-rank test. Perfusion was expressed as a percentage of the baseline, and 12- and 24-h data was analyzed using one-way analysis of variance and the Student t-test. Nonparametric data was compared using the Mann-Whitney U-test. A P value of <0.05 was considered statistically significant.
All MSCs increased 7-d survival after I/R injury and were superior to vehicle and keratinocytes (P < 0.05). All MSCs increased mesenteric perfusion more than vehicle at 12 and 24 h after injury (P < 0.05). All MSCs provided superior perfusion compared with keratinocytes at 24 h after injury (P < 0.05). Administration of each MSC line improved intestinal histology after I/R injury (P < 0.05). Multiple proinflammatory chemokines were downregulated after the application of MSCs, suggesting a decreased inflammatory response after MSC therapy.
Transplantation of MSCs after intestinal I/R injury, irrespective of a tissue source, significantly increases survival and mesenteric perfusion and at the same time limits intestinal damage and inflammation. Further studies are needed to identify the mechanism that these cells use to promote improved outcomes after injury.
间充质基质细胞（MSCs）移植可能是治疗肠道缺血的一种新方法。然而，尚未确定在损伤后能产生最大保护作用的最佳基质细胞来源。我们假设：（1）间充质基质细胞将提高存活率和肠系膜灌注，保留肠道组织学结构，并限制肠道缺血再灌注（I/R）损伤后的炎症反应；（2）从不同组织来源获取的间充质基质细胞在I/R损伤后对肠道具有同等的保护特性。
成年雄性小鼠麻醉后行中线剖腹术。取出内脏，确定小肠肠系膜根部，使用激光多普勒成像测定基线肠道灌注。用无损伤夹暂时夹闭肠系膜上动脉60分钟建立肠道缺血模型。缺血后移除夹子，让肠道恢复。在关闭腹腔前，将2×10⁶人脐带间充质基质细胞、骨髓间充质基质细胞或角质形成细胞溶于250μL磷酸盐缓冲盐水载体中注入腹腔。动物恢复12或24小时（用于灌注、组织学和炎症研究）或7天（用于存活研究）。使用对数秩检验分析存活数据。灌注以基线的百分比表示，12小时和24小时的数据使用单因素方差分析和Student t检验进行分析。非参数数据使用Mann-Whitney U检验进行比较。P值<0.05被认为具有统计学意义。
所有间充质基质细胞均提高了I/R损伤后的7天存活率，且优于载体和角质形成细胞（P<0.05）。在损伤后12小时和24小时，所有间充质基质细胞均比载体更能增加肠系膜灌注（P<0.05）。在损伤后24小时，与角质形成细胞相比，所有间充质基质细胞均提供了更好的灌注（P<0.05）。每种间充质基质细胞系给药后均改善了I/R损伤后的肠道组织学（P<0.05）。应用间充质基质细胞后多种促炎趋化因子下调，提示间充质基质细胞治疗后炎症反应降低。
肠道I/R损伤后移植间充质基质细胞，无论组织来源如何，均能显著提高存活率和肠系膜灌注，同时限制肠道损伤和炎症。需要进一步研究以确定这些细胞在损伤后促进改善预后所采用的机制。
