Supplementary Material for: Human Oral Mucosal Stem Cells Reduce Anastomotic Leak in an Animal Model of Colonic Surgery

Background: Anastomotic leak is regarded as one of the most feared complications of bowel surgery; avoiding leaks is a major priority. Attempts to reduce or eliminate leaks have included alternate anastomotic techniques. Human oral mucosa stem cells (hOMSC) are self-renewing and expandable cells derived from buccal mucosa. Studies have shown that hOMSC can accelerate tissue regeneration and wound healing. The objective of this study was to evaluate whether hOMSC can decrease anastomotic leak rates in a murine model of colon surgery. Methods: Two experiments were performed. In the first study, mice underwent colonic anastomosis using five interrupted sutures. hOMSC (n = 7) or normal saline (NS; n = 17) was injected into the colon wall at the site of the anastomosis. To evaluate whether hOMSC can impact anastomotic healing, the model was stressed by repeating the first experiment, reducing the number of sutures used for the construction of the anastomosis from five to four. Either hOMSC (n = 8) or NS (n = 20) was injected at the anastomosis. All mice that survived were sacrificed on postoperative day 7. Anastomotic leak rate, mortality, daily weight, and daily wellness scores were compared. Results: In the five-suture anastomosis, there were no differences in anastomotic leak rate, mortality, or daily weight. Mice that received hOMSC had significantly higher wellness scores on postoperative day 2 (p < 0.05). In the four-suture anastomosis, there was a significant decrease in leak rate (70% [NS] vs. 25% [hOMSC], p = 0.029) and higher wellness scores in mice that received hOMSC (p < 0.05). Conclusion: Our study suggests that injecting hOMSC at the colonic anastomosis can potentially reduce anastomotic leak and improve postoperative wellness in a murine model of colon surgery.

背景：吻合口漏（anastomotic leak）被视为肠道手术中最令人担忧的并发症之一，规避漏出是肠道手术的核心优先级目标。为减少乃至消除吻合口漏，学界已探索了多种备选吻合技术。人口腔黏膜干细胞（human oral mucosa stem cells，hOMSC）是源自颊黏膜的可自我更新、可扩增的细胞类群。已有研究证实，hOMSC可加速组织再生与伤口愈合。本研究旨在评估结肠手术小鼠模型中，hOMSC是否能够降低吻合口漏发生率。方法：本研究共开展两项实验。第一项实验中，小鼠接受结肠吻合术，采用5根间断缝线进行吻合。于吻合部位的肠壁内注射hOMSC（n=7）或生理盐水（normal saline，NS；n=17）。为探究hOMSC对吻合口愈合的影响，第二项实验对模型施加应激条件：将吻合术所用缝线数量从5根缩减至4根，其余操作与第一项实验保持一致。同样于吻合部位注射hOMSC（n=8）或生理盐水（n=20）。所有存活小鼠均于术后第7天实施安乐死并处以标本取材。对两组的吻合口漏发生率、死亡率、每日体重变化及每日健康评分进行比较分析。结果：在采用5根缝线的吻合术组中，两组的吻合口漏发生率、死亡率及每日体重变化均无显著统计学差异。但接受hOMSC注射的小鼠在术后第2天的健康评分显著更高（p<0.05）。在采用4根缝线的应激吻合术组中，hOMSC组的吻合口漏发生率显著降低（NS组为70%，hOMSC组为25%，p=0.029），且该组小鼠的术后健康评分同样显著更高（p<0.05）。结论：本研究结果表明，在结肠手术小鼠模型中，于结肠吻合部位注射hOMSC可潜在降低吻合口漏发生率，并改善小鼠术后健康状态。