Heterogenous acellular dermal matrix seeded with adipose derived stem cells for urethral reconstruction in a rabbit model

Abstract

Objective To assess the feasibility of heterogeneous acellular dermal matrix(ADM)seeded with adipose derived stem cells(ADSC)for urethroplasty in a rabbit model.Methods ADSC were isolated from a rabbit and expanded in vitro,then identified by flow cytometry.We seeded ADSC onto the ADM and made it into tissue-engineered urethra.12 male rabbits were removed 1 cm urethra and divided into experiment group and control group.There were 6 rabbits in each group.Reconstructed urethra with tissueengineered urethra was used in experiment group,while unseeded ADM were used in control group.Urethrography was performed at 6 months after surgery.The animals were scarified at 3 and 6 months after surgery and the repaired urethra were harvested.H&E staining and immunohistochemical staining were performed with cytokeratin AE1/AE3 and smooth muscle desmin makers.Results The morphology of isolated ADSC was with long spindle cross-links,and had multicentral growth.Flow cytometry showed that the ADSC expressed CD166,CD105,CD90 and CD44,but not expressed CD45 and CD13.The cells could growth well on the ADM and showed good biocompatibility with it.All animals could void normally,urethrography showed there was no significant stenosis.3 months after surgery,the experiment group appeared regenerated smooth muscle but not in the control group,both groups did not regenerate urothelium.At 6 months urothelium and smooth muscle cells could be observed in the experiment group,but only the smooth muscle was evident in the control group.Conclusions By applying tissue engineering methods,we can seed the ADSC onto the heterogeneous ADM and make it into tissue-engineered urethra,which can help improve the reconstructive effect of urethra. Key words: Tissue engineering; Urethra; Adipose derived stem Cells; Acellular dermal matrix