College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea.
Int J Mol Sci. 2024 Nov 12;25(22):12132. doi: 10.3390/ijms252212132.
Bioengineered livers are currently an acceptable alternative to orthotopic liver transplants to overcome the scarcity of donors. However, the challenge of using a bioengineered liver is the lack of an intact endothelial layer in the vascular network leading to thrombosis. Heparin-modified surfaces have been demonstrated to decrease thrombogenicity in earlier research. However, in our study, we aimed to apply heparin immobilization to enhance the hemocompatibility, endothelial cell (EC) adhesion, and angiogenesis of rat decellularized liver scaffolds (DLS). Heparin was immobilized on the DLS by the end-point attachment technique. The scaffold's hemocompatibility was assessed using ex vivo blood perfusion and platelet adhesion studies. The heparinized scaffold (HEP-DLS) showed a significantly reduced thrombogenicity and platelet aggregation. HEP-DLS was recellularized with EA.hy926 cells via the portal vein and maintained in the bioreactor for 7 days, showing increased EC adhesion and coverage within the blood vessels. The Resazurin reduction assay confirmed the presence of actively proliferating cells in the HEP-DLS. The scaffolds were implanted subcutaneously into the dorsum of mice for 21 days to evaluate cell migration and angiogenesis. The results showed significant increases in the number of blood vessels in the HEP-DLS group. Our results demonstrated that heparin immobilization reduces thrombosis, promotes re-endothelialization, and enhances angiogenesis in DLS. The research provides insight into the potential use of heparin in the formation of a functioning vasculature.
生物工程肝脏目前是克服供体短缺的原位肝移植的可接受替代品。然而，使用生物工程肝脏的挑战是血管网络中缺乏完整的内皮层，导致血栓形成。肝素修饰表面已被证明可降低早期研究中的血栓形成性。然而，在我们的研究中，我们旨在通过肝素固定化来增强大鼠脱细胞肝脏支架（DLS）的血液相容性、内皮细胞（EC）黏附和血管生成。肝素通过终点附着技术固定在 DLS 上。使用离体血液灌注和血小板黏附研究评估支架的血液相容性。肝素化支架（HEP-DLS）显示出明显降低的血栓形成性和血小板聚集。HEP-DLS 通过门静脉与 EA.hy926 细胞共培养，并在生物反应器中维持 7 天，显示血管内 EC 黏附和覆盖增加。Resazurin 还原测定法证实 HEP-DLS 中存在活跃增殖的细胞。将支架皮下植入小鼠背部 21 天，以评估细胞迁移和血管生成。结果表明 HEP-DLS 组的血管数量显著增加。我们的结果表明，肝素固定化可减少血栓形成，促进再内皮化，并增强 DLS 的血管生成。该研究为肝素在形成功能性脉管系统中的潜在用途提供了见解。
