METHODS: Biotubes (internal diameter 4 mm, length 50 cm, wall thickness 0.85 mm) were prepared by subcutaneous embedding of plastic moulds (Biotube Maker) in three goats for approximately two months. Allogenic Biotubes (length 10 cm [n = 2], 15 cm [n = 2], 22 cm [n = 2]) were bypassed to both carotid arteries by end to side anastomosis with their ligation between the anastomoses in another three goats. Residual Biotubes were examined for their mechanical properties. After four weeks, the harvested Biotubes were evaluated histologically.
RESULTS: All Biotubes had sufficient pressure resistance, approximately 3000 mmHg. Although wall thickening occurred at two proximal anastomosis sites, all six grafts were patent without luminal thrombus formation, stenosis, or aneurysm deformation throughout the implantation period. Endothelial cells covered both anastomosis sites almost completely, with partial covering in the central portion of the grafts. Furthermore, α smooth muscle actin positive cells infiltrated the middle layer along almost the entire graft length.
CONCLUSIONS: This preliminary study showed that small diameter, long, tissue engineered Biotubes could function properly as arterial bypass conduits in a large animal for one month without any abnormal change in vascular shape. Thus, small diameter, long Biotubes are potentially viable conduits, which are biocompatible and labour non-intensive, and therefore, suitable for clinical practice. Additionally, Biotubes can start the regeneration process in a short period of time.
方法:生物管(内径4mm,长度50厘米,壁厚0.85mm)通过将塑料模具(BiotubeMaker)皮下嵌入三只山羊中约两个月来制备。同种异体生物管(长度10厘米[n=2],15厘米[n=2],22cm[n=2])通过端侧吻合绕过两条颈动脉,并在另外三只山羊的吻合之间结扎。检查残留的生物管的机械性能。四周后,对收获的生物管进行组织学评价。
结果:所有生物管都具有足够的耐压性,约3000mmHg。尽管在两个近端吻合部位发生了壁增厚,所有六个移植物均未形成管腔血栓,狭窄,或在整个植入期间动脉瘤变形。内皮细胞几乎完全覆盖了两个吻合部位,移植物的中心部分覆盖。此外,α平滑肌肌动蛋白阳性细胞几乎沿整个移植物长度浸润中间层。
结论:这项初步研究表明,小直径,长,组织工程的生物管可以在大型动物中正常用作动脉旁路导管一个月,而血管形状没有任何异常变化。因此,小直径,长生物管是潜在可行的管道,生物相容性和非劳动密集型,因此,适合临床实践。此外,生物管可以在短时间内开始再生过程。