脱细胞羊膜基质负载BMSCs和EPCs修复犬尿道缺损

Transplantation of acellular amniotic membrane loaded with BMSCs and EPCs to repair canine urethral defect

旨在研究使用犬BMSCs和EPCs接种的脱细胞人羊膜基质修复犬长段管状尿道缺损的可行性,评估其修复效果。选取15只健康成年雄性杂种犬,随机分为5组,每组3只。建立会阴部3cm管状尿道缺损模型后,分别用负载骨髓间充质干细胞(BMSCs)、血管内皮祖细胞(EPCs)、BMSCs和EPCs混合的脱细胞羊膜基质修复缺损部位;用未种植细胞的脱细胞羊膜修复和缺损后不修复的犬只作为对照。通过术后排尿观察,尿道造影,剖检观察和组织学观察来评估修复效果。结果显示:BMSCs+EPCs混合组的犬只在术后排尿正常,新生尿道管腔光滑平整,无尿道狭窄,组织学观察显示新生上皮完整;BMSCs组的犬只尿道有小范围狭窄,剖检发现新生段有瘢痕;EPCs组的犬只排尿时间延长,新生尿道段狭窄,剖检显示新生段粗糙,瘢痕较多;组织学观察显示新生段上皮化不完整;羊膜修复组和自体修复组的犬只排尿异常,新生尿道段狭窄,剖检显示新生段瘢痕化严重,有多处皱缩,组织学观察显示上皮化不完整,仅为单层上皮,自体修复组的犬只尿道新生段几乎无上皮细胞覆盖。结果表明:证明用负载BMSCs和EPCs 2种细胞的脱细胞人羊膜基质可成功修复犬长段管状尿道缺损。

The purpose of this experiment is to study the feasibility of using human acellular amniotic matrix loaded with BMSCs and EPCs to repair canine long tubular urethral defect and evaluate its effect.15 healthy male mongrel dogs were selected and divided into 5groups randomly,with 3dogs in each group.After establishing the model of 3cm tubular urethral defect at perineum,the urethral defect models were repaired with acellular amniotic matrix seeded with bone marrow mesenchymal stem cells(BMSCs),endothelial progenitor cells(EPCs)and BMSCs mixed with EPCs,respectively.Dogs treated with acellular amniotic membrane without implantation cells and defective canine were as controls.The effect of urethral reconstruction was estimated by urination observation after surgery,retrograde urethrography,urethral anatomy check and histological analysis.Dogs in BMSCs+EPCs mixed group regained normal urination after operation,the new urethral canal was smooth and no urethral stricture was observed.The histological observation showed that the newborn epithelium was intact.In BMSCs group,a small-scale urethral stricture was found at perineum and scar was found in the newborn segment by dissection.In EPCs group,the urination time was prolonged and the urethral segment was narrow.The incomplete epithelialization was observed in the newborn segment by histological examination.Dogs in amniotic membrane repair group and autologous repair group had abnormal urination,urethra stricture,severe scarring and multiple shrinkage.Only single layer epithelium was found by histological examination.As for dogs in autologous repair group,there is almost no epithelial cell coverage in urethra.It demonstrated that human acellular amniotic membrane matrix loaded with both BMSCs and EPCs can successfully repair canine tubular urethral defects.