Hansjörg Wyss Department of Plastic Surgery, New York University School of Medicine, 540 First Avenue, New York, 10016, USA.
J Transl Med. 2021 Jan 6;19(1):16. doi: 10.1186/s12967-020-02674-5.
Cutaneous wounds in patients with diabetes exhibit impaired healing due to physiological impediments and conventional care options are severely limited. Multipotent stromal cells (MSCs) have been touted as a powerful new therapy for diabetic tissue repair owing to their trophic activity and low immunogenicity. However, variations in sources and access are limiting factors for broader adaptation and study of MSC-based therapies. Amniotic fluid presents a relatively unexplored source of MSCs and one with wide availability. Here, we investigate the potential of amniotic fluid-derived multipotent stromal cells (AFMSCs) to restore molecular integrity to diabetic wounds, amend pathology and promote wound healing.
We obtained third trimester amniotic fluid from term cesarean delivery and isolated and expanded MSCs in vitro. We then generated 10 mm wounds in Lepr diabetic mouse skin, and splinted them open to allow for humanized wound modeling. Immediately after wounding, we applied AFMSCs topically to the sites of injuries on diabetic mice, while media application only, defined as vehicle, served as controls. Post-treatment, we compared healing time and molecular and cellular events of AFMSC-treated, vehicle-treated, untreated diabetic, and non-diabetic wounds. A priori statistical analyses measures determined significance of the data.
Average time to wound closure was approximately 19 days in AFMSC-treated diabetic wounds. This was significantly lower than the vehicle-treated diabetic wounds, which required on average 27.5 days to heal (p < 0.01), and most similar to time of closure in wild type untreated wounds (an average of around 18 days). In addition, AFMSC treatment induced changes in the profiles of macrophage polarizing cytokines, resulting in a change in macrophage composition in the diabetic wound bed. We found no evidence of AFMSC engraftment or biotherapy induced immune response.
Treatment of diabetic wounds using amniotic fluid-derived MSCs encourages cutaneous tissue repair through affecting inflammatory cell behavior in the wound site. Since vehicle-treated diabetic wounds did not demonstrate accelerated healing, we determined that AFMSCs were therapeutic through their paracrine activities. Future studies should be aimed towards validating our observations through further examination of the paracrine potential of AFMSCs. In addition, investigations concerning safety and efficacy of this therapy in clinical trials should be pursued.
糖尿病患者的皮肤伤口由于生理障碍而愈合不良，传统的治疗方法选择受到严重限制。间充质干细胞（MSCs）因其营养活性和低免疫原性而被吹捧为糖尿病组织修复的强大新疗法。然而，来源和可及性的差异是限制更广泛应用和研究 MSC 为基础疗法的因素。羊水是一种相对未被探索的 MSC 来源，而且来源广泛。在这里，我们研究了羊水来源的多能基质细胞（AFMSCs）恢复糖尿病伤口分子完整性、纠正病理和促进伤口愈合的潜力。
我们从足月剖宫产中获得第三孕期羊水，并在体外分离和扩增 MSC。然后，我们在 Lepr 糖尿病小鼠的皮肤中产生 10mm 伤口，并将其撑开以允许进行人源化伤口建模。在受伤后，我们将 AFMSCs 局部应用于糖尿病小鼠的损伤部位，而仅应用培养基，定义为载体，作为对照。治疗后，我们比较了 AFMSC 治疗、载体治疗、未治疗的糖尿病和非糖尿病伤口的愈合时间以及分子和细胞事件。先验统计分析措施确定了数据的显著性。
AFMSC 治疗的糖尿病伤口的平均愈合时间约为 19 天。这明显低于载体治疗的糖尿病伤口，后者平均需要 27.5 天才能愈合（p<0.01），与未治疗的野生型伤口的愈合时间最为相似（平均约为 18 天）。此外，AFMSC 治疗诱导了巨噬细胞极化细胞因子的谱变化，导致糖尿病伤口床中巨噬细胞组成的变化。我们没有发现 AFMSC 植入或生物治疗诱导免疫反应的证据。
使用羊水来源的 MSC 治疗糖尿病伤口通过影响伤口部位的炎症细胞行为促进皮肤组织修复。由于载体治疗的糖尿病伤口没有表现出加速愈合，我们确定 AFMSC 是通过其旁分泌活性发挥治疗作用的。未来的研究应该通过进一步研究 AFMSC 的旁分泌潜力来验证我们的观察结果。此外，应该进行关于这种疗法在临床试验中的安全性和有效性的研究。
