A Tissue Engineering Study On Using Aortic Smooth Muscle Cells To Promote The Elasticity Of Dermal Substitute

Dermal substitute is an important component of the tissue engineering skin. Up to now, there is no dermal substitute that can produce elastin and form elastic fiber in vitro. In this study, we used aortic smooth muscle cells (ASMCs) as seed cells, collagen-chitin- glycosaminoglycans (GAG) as extracellular matrix, to construct dermal substitute by three-dimensional culture, and then to transplant the dermal substitute to rats subcutaneously. The elastic fibers produced by ASMCs during the three-dimensional culture and after transplantation were examined by Gomori' s aldehyde fuchsin staining and elastin immunohistochemistry. More over, we also carried out a comparison study of the two elastic fiber staining methods.The study of ASMCs in three-dimensional culture. After primary culture and subculture, ASMCs were mixed with collagen-chitin-GAG and cultured three-dimensionally. 98 percent of the subcultured cells were approved as ASMCs by a -Actin immunohistochemistry positive staining. After three-dimensional culture (far to two weeks), elastic fibers were detected in ASMC gels.The study of transplantation of ASMC-collagen-chitin-GAG gels to rats subcutaneously. After transplantation (far to four weeks), there were not remarkable leucocytes infiltration around the ASMC gels, indicating no transplantation rejection occurred. The host blood vessels and fibroblasts growing into the ASMC gels were observed. In gels, ASMCs increased in number and appeared the morphology as active synthesis. On the 7th day, the elastic fiber enhanced significantly than in vitro. Whereas on the 28th day, no elastic fiber was detected.The comparison of Gomori's aldehyde fuchsin staining and elastin immunohi'stochemistry. The rat aorta and skin sections were stained by Gomori's aldehyde fuchsin staining and elastin immunohistochemistry respectively. The elastic fibers can be stained by both methods, but the elastic membranes in aorta can only be shown by Gomori's staining completely. These results indicate that the Gomori's staining is more effective, simple and economical.