Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran.
Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, Iran; Department of Tissue Engineering and Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran.
Int J Biol Macromol. 2023 Dec 31;253(Pt 4):127041. doi: 10.1016/j.ijbiomac.2023.127041. Epub 2023 Sep 22.
Despite several progressions in the biofabrication of large-scale engineered tissues, direct biopri nting of perfusable three-dimensional (3D) vasculature remained unaddressed. Developing a feasible method to generate cell-laden thick tissue with an effective vasculature network to deliver oxygen and nutrient is crucial for preventing the formation of necrotic spots and tissue death. In this study, we developed a novel technique to directly bioprint 3D cell-laden prevascularized construct. We developed a novel bioink by mixing decellularized human amniotic membrane (dHAM) and alginate (Alg) in various ratios. The bioink with encapsulated human vein endothelial cells (HUVECs) and a crosslinker, CaCl were extruded via sheath and core nozzle respectively to directly bioprint a perfusable 3D vasculature construct. The various concentration of bioink was assessed from several aspects like biocompatibility, porosity, swelling, degradation, and mechanical characteristics, and accordingly, optimized concentration was selected (Alg 4 %w/v - dHAM 0.6 %w/v). Then, the crosslinked bioink without microchannel and the 3D bioprinted construct with various microchannel distances (0, 1.5 mm, 3 mm) were compared. The 3D bioprinted construct with a 1.5 mm microchannels distance demonstrated superiority owing to its 492 ± 18.8 % cell viability within 14 days, excellent tubulogenesis, remarkable expression of VEGFR-2 which play a crucial role in endothelial cell proliferation, migration, and more importantly angiogenesis, and neovascularization. This perfusable bioprinted construct also possess appropriate mechanical stability (32.35 ± 5 kPa Young's modulus) for soft tissue. Taking these advantages into the account, our new bioprinting method possesses a prominent potential for the fabrication of large-scale prevascularized tissue to serve for regenerative medicine applications like implantation, drug-screening platform, and the study of mutation disease.
尽管在大规模工程组织的生物制造方面取得了一些进展，但直接生物打印可灌注的三维（3D）血管仍然没有得到解决。开发一种可行的方法来生成含有有效血管网络的细胞负载厚组织，以输送氧气和营养物质，对于防止坏死点和组织死亡的形成至关重要。在这项研究中，我们开发了一种直接生物打印 3D 细胞负载预血管化构建体的新技术。我们通过以不同比例混合脱细胞人羊膜（dHAM）和藻酸盐（Alg）来开发一种新型生物墨水。含有包封的人静脉内皮细胞（HUVEC）和交联剂 CaCl 的生物墨水分别通过鞘和芯喷嘴挤出，以直接生物打印可灌注的 3D 血管构建体。从生物相容性、孔隙率、膨胀、降解和机械特性等几个方面评估了不同浓度的生物墨水，并相应地选择了优化的浓度（Alg 4%w/v-dHAM 0.6%w/v）。然后，比较了没有微通道的交联生物墨水和具有不同微通道距离（0、1.5mm、3mm）的 3D 生物打印构建体。具有 1.5mm 微通道距离的 3D 生物打印构建体具有优越性，因为在 14 天内其细胞活力为 492±18.8%，管腔形成良好，VEGFR-2 的表达显著，VEGFR-2 在内皮细胞增殖、迁移中起着至关重要的作用，更重要的是血管生成和新生血管形成。这种可灌注的生物打印构建体还具有适当的机械稳定性（32.35±5kPa 的杨氏模量），适用于软组织。考虑到这些优势，我们的新生物打印方法具有制造大规模预血管化组织的突出潜力，可用于再生医学应用，如植入、药物筛选平台和突变疾病的研究。
