Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
Department of Chemical and Biochemical Engineering, Thompson Engineering Building, The University of Western Ontario, London, Ontario, Canada.
J Tissue Eng Regen Med. 2020 Dec;14(12):1827-1840. doi: 10.1002/term.3133. Epub 2020 Oct 2.
Tissue-engineering approaches hold promise to address the need in plastic and reconstructive surgery for new therapies that promote stable adipose tissue regeneration. Previous studies have demonstrated the potential of combining decellularized adipose tissue (DAT) scaffolds with adipose-derived stromal cells (ASCs) for volume augmentation applications. With the goal of enhancing in vivo angiogenesis and adipogenesis, this study evaluated the effects of culturing human ASCs on DAT scaffolds within a perfusion bioreactor. Using this system, the impact of both dynamic culture and hypoxic preconditioning were explored in vitro and in vivo. Initial studies compared the effects of 14 days of culture within the perfusion bioreactor under hypoxia (2% O ) or normoxia (~20% O ) on human ASC expansion and expression of hypoxia inducible factor-1 alpha (HIF-1α) in vitro relative to static cultured controls. The findings indicated that culturing within the bioreactor under hypoxia significantly increased ASC proliferation on the DAT, with a higher cell density observed in the scaffold periphery. Subsequent characterization in a subcutaneous implant model in athymic nude mice revealed that in vivo angiogenesis and adipogenesis were markedly enhanced when the ASCs were cultured on the DAT within the perfusion bioreactor under hypoxia for 14 days prior to implantation relative to the other culture conditions, as well as freshly seeded and unseeded DAT control groups. Overall, dynamic culture within the perfusion bioreactor system under hypoxia represents a promising approach for preconditioning ASCs on DAT scaffolds to enhance their capacity to stimulate angiogenesis and host-derived adipose tissue regeneration.
组织工程方法有望满足整形和重建外科领域的需求，为促进稳定的脂肪组织再生提供新的治疗方法。先前的研究已经证明了将脱细胞脂肪组织（DAT）支架与脂肪来源的基质细胞（ASCs）结合用于体积增加应用的潜力。本研究旨在增强体内血管生成和脂肪生成，评估了在灌注生物反应器中培养人 ASC 对 DAT 支架的影响。使用该系统，体外和体内探索了动态培养和低氧预处理的影响。初步研究比较了在低氧（2%O ）或常氧（~20%O ）下在灌注生物反应器中培养 14 天对人 ASC 扩增和缺氧诱导因子-1α（HIF-1α）表达的影响，与静态培养对照相比。研究结果表明，在生物反应器中低氧培养显著增加了 DAT 上 ASC 的增殖，在支架外围观察到更高的细胞密度。随后在无胸腺裸鼠皮下植入模型中的特征分析表明，与其他培养条件以及新鲜接种和未接种 DAT 对照组相比，在植入前将 ASC 在低氧条件下在灌注生物反应器中培养 14 天，然后在 DAT 上培养，可显著增强体内血管生成和脂肪生成。总的来说，在低氧灌注生物反应器系统中进行的动态培养代表了一种有前途的方法，可用于对 DAT 支架上的 ASC 进行预处理，以增强其刺激血管生成和宿主来源的脂肪组织再生的能力。
