生物压膜上皮种植技术促进带蒂大网膜包裹脱上皮细胞同种异体气管移植再上皮化的实验研究

Tracheal allotransplantation has been a hot topic in the field of tracheal reconstruction surgery. Revascularization of the tracheal allograft and control of rejection are pivotal to the success of tracheal transplantation. Heterotopic momentum majus wrapping promotes revascuarization of the allograft, whereas rejection still poses a major challenge. Previous studies have demonstrated that complete re-epitheliarization of the lumen of the allograft can significantly reduce the duration of immunosuppression therapy, while achieving long-term patency. In this study, we plan to selectively de-epitheliarize the tracheal allograft by means of intraluminal digestion using decellularize agents, so that the immunogenicity of the allograft can be degraded. We then plan to seed the autologous epithelial cells onto the lumen of the allograft using the Poly (Left-lactide-co-ε-caprolactone/Col) nano-fiber membrane to improve the efficiency of epithelium seeding and optimize the epithelium reconstruction, and finally reduce the duration of immunosuppression. Heterotopic wrapping by omentum majus is expected to revascularize the tracheal allograft, maintain the vitality of the chondrocytes and prevent allograft malacia. The re-epitheliarized allograft wrapped in omentum majus will be orthotopically transplanted to repair cervical tracheal defect in a rabbit model. Thus we expect to solve the problem of allograft revascularization and rejection. The success of our study will lay the foundation of clinical application of tracheal transplantation.

同种异体气管移植一直是气管重建外科领域的研究热点。解决移植气管血供和免疫排斥是移植成功的关键。通过大网膜异位包裹气管可以促进供体气管血运重建，但免疫排斥仍然是亟待解决的难题。研究证实移植气管的完全再上皮化可以明显缩短抗排异药的使用周期，并保证移植气管远期通畅。本课题通过采用脱细胞剂管腔内消化法对供体气管进行选择性脱上皮细胞处理，以达到降低移植物免疫原性的目的；通过应用PLLAL/Col纳米纤维膜压膜技术对移植气管内壁进行上皮细胞种植，提高上皮细胞种植效率和优化上皮重构，以期达到移植气管粘膜快速、完全再上皮化，缩短免疫排异药物使用时间的目的；通过大网膜包埋对移植气管提供血供，以保持软骨细胞活性，防止移植气管软化，最终一并解决移植气管再血管化和免疫排斥的难题。随后将带蒂大网膜包裹的再上皮化供体气管二期原位移植，修复兔颈段气管节段性缺损，为该技术应用于临床打下坚实的基础。

同种异体气管移植一直是气管重建外科领域的研究热点。同时解决移植气管的免疫排斥，上皮化，软骨化及血管化是移植成功的关键。本课题通过采用脱细胞剂管腔内消化法对供体气管进行选择性脱上皮细胞处理，可以降低移植物免疫原性；通过优化上皮细胞培养策略可以获取足够数量的上皮细胞及培养上皮膜片，为上皮化提供保障；我们通过一系列技术（3D打印技术，静电纺丝技术，冷冻干燥技术）对组织工程气管软骨构建材料进行优化，构建出具有足够力学强度的长段组织工程气管软骨；随后我们将该新生气管软骨植入兔颈部肌肉下，经过4周预埋植可以实现血管化。最后我们整合上述技术将血管化的组织工程气管用于修复兔颈段气管节段性缺损，实现了兔长期存活（6个月），未出现明显免疫排斥反应，尸解组织学检测显示修复段气管同时具有良好的软骨化，血管化及上皮化。因此，本研究同时解决了移植气管的免疫排斥，上皮化，软骨化及血管化问题，为该组织工程气管应用于临床打下坚实的基础。