Xu Yong, Wang Zongxin, Hua Yujie, Zhu Xinsheng, Wang Yahui, Duan Liang, Zhu Linyong, Jiang Gening, Xia Huitang, She Yunlang, Zhou Guangdong
Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, PR China.
Research Institute of Plastic Surgery, Weifang Medical University, Weifang, Shandong, PR China; Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, PR China; National Tissue Engineering Center of China, Shanghai, PR China.
Mater Sci Eng C Mater Biol Appl. 2021 Jan;120:111628. doi: 10.1016/j.msec.2020.111628. Epub 2020 Oct 22.
Repair of long segmental trachea defects is always a great challenge in the clinic. The key to solving this problem is to develop an ideal trachea substitute with biological function. Using of a decellularized trachea matrix based on laser micropore technique (LDTM) demonstrated the possibility of preparing ideal trachea substitutes with tubular shape and satisfactory cartilage regeneration for tissue-engineered trachea regeneration. However, as a result of the very low cell adhesion of LDTM, an overly high concentration of seeding cell is required, which greatly restricts its clinical translation. To address this issue, the current study proposed a novel strategy using a photocrosslinked natural hydrogel (PNH) carrier to enhance cell retention efficiency and improve tracheal cartilage regeneration. Our results demonstrated that PNH underwent a rapid liquid-solid phase conversion under ultraviolet light. Moreover, the photo-generated aldehyde groups in PNH could rapidly react with inherent amino groups on LDTM surfaces to form imine bonds, which efficiently immobilized the cell-PNH composite to the surfaces of LDTM and/or maintained the composite in the LDTM micropores. Therefore, PNH significantly enhanced cell-seeding efficiency and achieved both stable cell retention and homogenous cell distribution throughout the LDTM. Moreover, PNH exhibited excellent biocompatibility and low cytotoxicity, and provided a natural three-dimensional biomimetic microenvironment to efficiently promote chondrocyte survival and proliferation, extracellular matrix production, and cartilage regeneration. Most importantly, at a relatively low cell-seeding concentration, homogeneous tubular cartilage was successfully regenerated with an accurate tracheal shape, sufficient mechanical strength, good elasticity, typical lacuna structure, and cartilage-specific extracellular matrix deposition. Our findings establish a versatile and efficient cell-seeding strategy for regeneration of various tissue and provide a satisfactory trachea substitute for repair and functional reconstruction of long segmental tracheal defects.
长节段气管缺损的修复在临床上一直是一项巨大的挑战。解决这一问题的关键在于开发一种具有生物功能的理想气管替代物。基于激光微孔技术的去细胞气管基质（LDTM）的应用证明了制备具有管状形状且软骨再生效果良好的理想气管替代物用于组织工程气管再生的可能性。然而，由于LDTM的细胞黏附性极低，需要过高浓度的接种细胞，这极大地限制了其临床转化。为了解决这个问题，当前研究提出了一种新策略，即使用光交联天然水凝胶（PNH）载体来提高细胞保留效率并改善气管软骨再生。我们的结果表明，PNH在紫外光下经历快速的液-固相变。此外，PNH中光生成的醛基可与LDTM表面的固有氨基迅速反应形成亚胺键，从而有效地将细胞-PNH复合物固定在LDTM表面和/或使复合物维持在LDTM微孔中。因此，PNH显著提高了细胞接种效率，并在整个LDTM中实现了稳定的细胞保留和均匀的细胞分布。此外，PNH表现出优异的生物相容性和低细胞毒性，并提供了一个天然的三维仿生微环境，以有效地促进软骨细胞的存活和增殖、细胞外基质的产生以及软骨再生。最重要的是，在相对较低的细胞接种浓度下，成功再生出了形状精确、具有足够机械强度、良好弹性、典型陷窝结构以及软骨特异性细胞外基质沉积的均匀管状软骨。我们的研究结果建立了一种通用且高效的细胞接种策略用于各种组织的再生，并为长节段气管缺损的修复和功能重建提供了一种令人满意的气管替代物。
