Human Amniotic Mesenchymal Cells Combined With Electrospun Scaffolds To Repair Rabbit Urethral Defect

Objective: based on rabbit urethral defect model, to explore the effect of human amnioticmesenchymal cells(hAMCs) as seed cells combine with biodegradable electrospunscaffolds(PLLA/PEG) for rabbit urethral defect.Methods: trypsin-collagenase method was used to extract hAMCs from fresh humanamniotic membrane. PLLA/PEG nanofibrous scaffolds was manufactured by using theelectrospinning technique. The length of2.0cm urethra was cut off from27New Zealandmale rabbits to build urethral defect rabbit model, which were then randomly divided into3groups: experimental group (A, n=9), control group (B, n=9) and blank control group (C,n=9). In group A, the exponential growth of hAMCs grew on the PLLA/PEG scaffold for48hours and then was used to repair artificial rabbit uerthral defect; In group B,nanofibrous scaffold was used to rebuild the rabbit urethral defect; In group C, urethraldefect was reconstructed by urethral end-to-end anastomosis. Three rabbit in each groupwere killed4,8and12weeks after urethral operation respectively to observe urethralmorphology, tissue constructure, luminal patency and complication rate (including stoneformation, urinary fistula and urethral stricture) by using pathologic methods and urethralradiography.Results: In group A, the re-building rabbit urethral tract by using hAMCs and PLLA/PEGscaffolds showed a nearly normal urethral construction with good gross morphological andhistological formation, compared with the urethral tract in the form of structural disorder ingroup B and group C. Twelve weeks after urethral operation, urinary radiography showedthat there was no urinary stricture in group A, compared with urinary stricture in differentdegree in group B and group C. About complication rate, group A was significantly lowerthan group B and group C,3.7%vs.44.44%vs.81.48%,ρ＜0.05.Conclusions:1) hAMCs was a potential seed stem cells for rabbit urethral defect rebuilding.2) Electrospinning Nanofibrous PLLA/PEG scaffold maybe a ideal materialfor urethral tissue engineering with good tissue compatibility and no cell toxicity.3)hAMCs combined with PLLA/PEG scaffolds proved can repair rabbit urethral defect,which for urethral tissue engineering provide more choice and methods.