Department of Urology, Huashan Hospital, Fudan University, No. 12 WuLuMuQi Middle Road, 200040Shanghai, China.
Fudan Institute of Urology, Huashan Hospital, Fudan University, 200040Shanghai, China.
ACS Biomater Sci Eng. 2022 Nov 14;8(11):4909-4920. doi: 10.1021/acsbiomaterials.2c00695. Epub 2022 Oct 6.
Treatment of urethral mucosa defects is a major challenge in urology. Synthetic materials or autologous mucosa does not provide satisfactory treatment options for long-term or large urethral mucosa defects. In response to this problem, we used autologous adipose-derived stem cells (ADSCs) to synthesize cell sheets in vitro for repairing urethral mucosa defect models. In order to monitor the localization and distribution of cell sheets in vivo, cells and sheets were labeled with indocyanine green (ICG) and the second near-infrared (NIR-II) fluorescence imaging was performed. ICG-based NIR-II imaging can successfully track ADSCs and sheets in vivo up to 8 W. Then, rabbit urethral mucosa defect models were repaired with ICG-ADSCs sheets. At 3 months after operation, retrograde urethrography showed that ADSC sheets could effectively repair urethral mucosa defect and restore urethral patency. Histological analysis showed that in ADSC sheet groups, continuous epithelial cells covered the urethra at the transplantation site, and a large number of vascular endothelial cells could also be seen. In the cell-free sheet group, there was no continuous epithelial cell coverage at the repair site of the urethra, and the expression of pro-inflammatory factor TNF-α was increased. It shows that the extracellular matrix alone without cells is not suitable for repairing urethral defects. Surviving ADSCs in the sheets may play a key role in the repair process. This study provides a new tracing method for tissue engineering to dynamically track grafts using an NIR-II imaging system. The ADSC sheets can effectively restore the structure and function of the urethra. It provides a new option for the repair of urethral mucosa defects.
尿道黏膜缺损的治疗是泌尿科的一大难题。合成材料或自体黏膜并不能为长期或大面积的尿道黏膜缺损提供满意的治疗选择。针对这一问题，我们使用自体脂肪源性干细胞（ADSCs）在体外合成细胞片，用于修复尿道黏膜缺损模型。为了监测细胞片在体内的定位和分布，用吲哚菁绿（ICG）对细胞和片进行标记，并进行第二次近红外（NIR-II）荧光成像。基于 ICG 的 NIR-II 成像可以成功地在体内追踪 ADSC 和片长达 8 周。然后，用 ICG-ADSCs 片修复兔尿道黏膜缺损模型。术后 3 个月逆行尿道造影显示，ADSC 片能有效修复尿道黏膜缺损，恢复尿道通畅。组织学分析表明，在 ADSC 片组中，连续的上皮细胞覆盖在移植部位的尿道上，还可以看到大量的血管内皮细胞。在无细胞片组中，尿道修复部位没有连续的上皮细胞覆盖，促炎因子 TNF-α的表达增加。这表明没有细胞的细胞外基质本身并不适合修复尿道缺损。片内存活的 ADSC 可能在修复过程中发挥关键作用。本研究为组织工程提供了一种新的示踪方法，使用 NIR-II 成像系统对移植物进行动态跟踪。ADSC 片能有效恢复尿道的结构和功能，为尿道黏膜缺损的修复提供了新的选择。
