The development of an ideal vascular prosthesis represents an important challenge in terms of the treatment of cardiovascular diseases with respect to which new materials are being considered that have produced promising results following testing in animal models. This study focuses on nanofibrous polycaprolactone-based grafts assessed by means of histological techniques 10 days and 6 months following suturing as a replacement for the rat aorta. A novel stereological approach for the assessment of cellular distribution within the graft thickness was developed. The cellularization of the thickness of the graft was found to be homogeneous after 10 days and to have changed after 6 months, at which time the majority of cells was discovered in the inner layer where the regeneration of the vessel wall was found to have occurred. Six months following implantation, the endothelialization of the graft lumen was complete, and no vasa vasorum were found to be present. Newly formed tissue resembling native elastic arteries with concentric layers composed of smooth muscle cells, collagen, and elastin was found in the implanted polycaprolactone-based grafts. Moreover, the inner layer of the graft was seen to have developed structural similarities to the regular aortic wall. The grafts appeared to be well tolerated, and no severe adverse reaction was recorded with the exception of one case of cartilaginous metaplasia close to the junctional suture.

Department of Biomedical Engineering Michigan Technological University 1400 Townsend Drive Houghton MI 49931 USA

Department of Chemistry Bioengineering Faculty of Science Humanities and Education Technical University of Liberec Studentska 1402 2 461 17 Liberec Czech Republic

Department of Histology and Embryology and Biomedical Centre Faculty of Medicine in Pilsen Charles University Karlovarska 48 301 66 Pilsen Czech Republic

Department of Materials Science and Engineering Michigan Technological University 1400 Townsend Drive Houghton MI 49931 USA

Department of Nonwoven and Nanofibrous Materials Technical University of Liberec Studentska 1402 2 461 17 Liberec Czech Republic

Department of Physics Faculty of Science Humanities and Education Technical University of Liberec Studentska 1402 2 461 17 Liberec Czech Republic

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