Hafez Ashraf T, Afshar Kourosh, Bägli Darius J, Bahoric Andre, Aitken Karen, Smith Charles R, Khoury Antoine E
Urology and Nephrology Center, Mansoura University, Mansoura, Egypt.
J Urol. 2005 Oct;174(4 Pt 2):1663-7; discussion 1667-8. doi: 10.1097/01.ju.0000177727.56790.98.
In a pilot study we developed a cell transfer technology for populating demucosalized colonic segments with bladder urothelium. This process was achieved through aerosol transfer of a single cell suspension consisting of bladder urothelial cells, smooth muscle cells and fibrin glue onto demucosalized colonic segments. We further evaluate this new concept in a controlled study.
The study was performed on 20 piglets (20 kg). In all animals 50% of the bladder with excised, and a 10 cm segment of the sigmoid was isolated. Animals were then equally divided into 5 groups of 1) colocystoplasty only, 2) demucosalized colocystoplasty, 3) demucosalized colocystoplasty plus covering of the demucosalized sigmoid with fibrin glue only, 4) aerosol application of fibrin glue with single cell suspension of urothelial cells only to the demucosalized colon, and 5) aerosol application of fibrin glue with urothelial and smooth muscle cells to the demucosalized colon. The 4 corners of the augmented segments were marked with 5-zero polypropylene sutures. Animals were sacrificed 6 weeks later and the surface area of the augmented segment was measured. Segments were submitted to histological and immunohistochemical analysis.
The surface area of the augmented segments showed an increase in group 1 animals, stabilization in groups 4 and 5, and marked reduction in groups 2 and 3. On hematoxylin and eosin, and Masson trichrome staining all group 1 animals showed normal colonic epithelium of the augment. All animals in groups 2 and 3 showed excessive scarring with urothelial coverage only at the augment periphery, while the central augment area showed no epithelium. Segments from groups 4 and 5 showed confluent epithelial covering with no fibrosis. There was no evidence of colonic epithelial re-growth in any animal in groups 2 to 5. Cytokeratin 7 and uroplakin III staining demonstrated complete coverage of the augmented segment with urothelium only in groups 4 and 5.
The addition of aerosolized cells of urological origin is a viable augmentation approach that appears to achieve the much sought after inhibition of intrinsic fibrosis and contraction of colonic segments when incorporated into the urinary tract without this cellular component. Moreover, this technique appears to provide a histologically normal, confluent urothelium, which sets the stage for prevention of the well-documented biochemical aberrations inherent in augments containing gastrointestinal epithelium. While successful in this model regardless of the incorporation of urological smooth muscle cells, chronic studies are now warranted to validate the short-term results as well as determine whether the urological mesenchymal population (smooth muscle) will be required to sustain the uroepithelial phenotype in the long term.
在一项初步研究中，我们开发了一种细胞移植技术，用于用膀胱尿路上皮细胞填充去黏膜化的结肠段。该过程是通过将由膀胱尿路上皮细胞、平滑肌细胞和纤维蛋白胶组成的单细胞悬液以气溶胶形式转移到去黏膜化的结肠段上实现的。我们在一项对照研究中进一步评估了这一新概念。
该研究在20头体重20千克的仔猪上进行。在所有动物中，切除50%的膀胱，并分离出10厘米长的乙状结肠段。然后将动物平均分为5组：1）仅行结肠膀胱扩大术；2）去黏膜化结肠膀胱扩大术；3）去黏膜化结肠膀胱扩大术加仅用纤维蛋白胶覆盖去黏膜化的乙状结肠；4）仅将纤维蛋白胶与尿路上皮细胞单细胞悬液以气溶胶形式应用于去黏膜化结肠；5）将纤维蛋白胶与尿路上皮细胞和平滑肌细胞以气溶胶形式应用于去黏膜化结肠。扩大段的四个角用5-0聚丙烯缝线标记。6周后处死动物，测量扩大段的表面积。将各段进行组织学和免疫组化分析。
扩大段的表面积在第1组动物中增加，在第4组和第5组中稳定，在第2组和第3组中显著减小。苏木精-伊红染色和Masson三色染色显示，所有第1组动物扩大段的结肠上皮正常。第2组和第3组的所有动物均显示过度瘢痕形成，仅在扩大段周边有尿路上皮覆盖，而扩大段中央区域无上皮。第4组和第5组的各段显示上皮融合覆盖且无纤维化。在第2至5组的任何动物中均未发现结肠上皮再生的证据。细胞角蛋白7和尿桥蛋白III染色显示，仅在第4组和第5组中尿路上皮完全覆盖了扩大段。
添加源自泌尿外科的雾化细胞是一种可行的扩大方法，当将其纳入尿路而不包含该细胞成分时，似乎能实现人们所追求的抑制固有纤维化和结肠段收缩的效果。此外，该技术似乎能提供组织学上正常的、融合的尿路上皮，为预防含胃肠道上皮的扩大段中固有且已充分记录的生化异常奠定了基础。尽管在该模型中无论是否加入泌尿外科平滑肌细胞均取得成功，但现在需要进行长期研究以验证短期结果，并确定从长期来看是否需要泌尿外科间充质细胞群（平滑肌）来维持尿路上皮表型。
