Cell-free tissue-engineered vascular grafts provide a promising alternative to treat cardiovascular disease but timely endothelialization is essential for ensuring patency and proper functioning post-implantation. Recent studies from our lab showed that blood cells like monocytes (MCs) and macrophages (Mφ) may contribute directly to cellularization and regeneration of bioengineered arteries in small and large animal models. While MCs and Mφ are leukocytes that are part of the innate immune response, they share common developmental origins with endothelial cells (ECs) and are known to play crucial roles during vessel formation (angiogenesis) and vessel repair after inflammation/injury. They are highly plastic cells that polarize into proinflammatory and anti-inflammatory phenotypes upon exposure to cytokines; and differentiate into other cell types, including EC-like cells, in the presence of appropriate chemical and mechanical stimuli. This review focuses on the developmental origins of MCs and ECs; the role of MCs and Mφ in vessel repair/regeneration during inflammation/injury; and the role of chemical signaling and mechanical forces in Mφ inflammation that mediates vascular graft regeneration. We postulate that comprehensive understanding of these mechanisms will better inform the development of strategies to coax MCs/Mφ into endothelializing the lumen and regenerate the smooth muscle layers of cell-free bioengineered arteries and veins that are designed to treat cardiovascular diseases and perhaps the native vasculature as well.

中文翻译：

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利用单核细胞/巨噬细胞的潜力再生组织工程血管移植物

无细胞组织工程血管移植物为治疗心血管疾病提供了一种有前途的替代方案，但及时的内皮化对于确保植入后的通畅和正常功能至关重要。我们实验室最近的研究表明，单核细胞 (MC) 和巨噬细胞 (Mφ) 等血细胞可能直接有助于小型和大型动物模型中生物工程动脉的细胞化和再生。虽然 MC 和 Mφ 是白细胞，是先天免疫反应的一部分，但它们与内皮细胞 (EC) 具有共同的发育起源，并且已知在炎症/损伤后的血管形成（血管生成）和血管修复过程中发挥着至关重要的作用。它们是高度可塑性的细胞，在接触细胞因子后会极化为促炎和抗炎表型。在适当的化学和机械刺激下，分化成其他细胞类型，包括 EC 样细胞。本综述重点关注 MC 和 EC 的发育起源； MCs 和 Mφ 在炎症/损伤期间血管修复/再生中的作用；以及化学信号和机械力在介导血管移植物再生的 Mφ 炎症中的作用。我们假设，对这些机制的全面理解将更好地指导开发策略，以诱导 MCs/Mφ 内皮化管腔并再生无细胞生物工程动脉和静脉的平滑肌层，这些动脉和静脉旨在治疗心血管疾病以及可能的天然脉管系统以及。