University Hospital of Würzburg, Chair of Tissue Engineering and Regenerative Medicine, 97070, Würzburg, Germany.
University Hospital of Würzburg, Department of General, Visceral, Vascular and Pediatric Surgery, 97080, Würzburg, Germany.
Sci Rep. 2018 Mar 16;8(1):4719. doi: 10.1038/s41598-018-22688-w.
In tissue engineering, the generation and functional maintenance of dense voluminous tissues is mainly restricted due to insufficient nutrient supply. Larger three-dimensional constructs, which exceed the nutrient diffusion limit become necrotic and/or apoptotic in long-term culture if not provided with an appropriate vascularization. Here, we established protocols for the generation of a pre-vascularized biological scaffold with intact arterio-venous capillary loops from rat intestine, which is decellularized under preservation of the feeding and draining vascular tree. Vessel integrity was proven by marker expression, media/blood reflow and endothelial LDL uptake. In vitro maintenance persisted up to 7 weeks in a bioreactor system allowing a stepwise reconstruction of fully vascularized human tissues and successful in vivo implantation for up to 4 weeks, although with time-dependent decrease of cell viability. The vascularization of the construct lead to a 1.5× increase in cellular drug release compared to a conventional static culture in vitro. For the first time, we performed proof-of-concept studies demonstrating that 3D tissues can be maintained within a miniaturized vascularized scaffold in vitro and successfully implanted after re-anastomosis to the intrinsic blood circulation in vivo. We hypothesize that this technology could serve as a powerful platform technology in tissue engineering and regenerative medicine.
在组织工程中，由于营养供应不足，大量密集组织的生成和功能维持受到限制。如果没有适当的血管生成，如果不提供适当的血管生成，较大的三维构建体（超过营养扩散极限）在长期培养中会发生坏死和/或凋亡。在这里，我们建立了从大鼠肠道生成具有完整动静脉毛细血管环的预血管化生物支架的方案，该支架在保留喂养和引流血管树的情况下脱细胞化。通过标志物表达、培养基/血液再循环和内皮 LDL 摄取证明了血管完整性。在生物反应器系统中，体外维持可持续长达 7 周，允许逐步重建完全血管化的人体组织，并成功植入体内长达 4 周，尽管细胞活力随时间呈下降趋势。与传统的体外静态培养相比，构建体的血管化导致细胞药物释放增加 1.5 倍。我们首次进行了概念验证研究，证明了 3D 组织可以在体外维持在小型化的血管化支架内，并在重新吻合到体内固有血液循环后成功植入。我们假设这项技术可以作为组织工程和再生医学中的强大平台技术。
