Institute of Biomaterials and Biomedical Engineering, University of Toronto, ON, Canada.
Acta Biomater. 2011 Jan;7(1):115-22. doi: 10.1016/j.actbio.2010.08.014. Epub 2010 Aug 20.
A degradable, polar, hydrophobic, ionic polyurethane (D-PHI), with physical properties comparable to those of peripheral arterial vascular tissue, was evaluated for monocyte interactions with two different physical forms: two-dimensional films and three-dimensional porous scaffolds. Monocytes, isolated from human whole blood, were seeded onto D-PHI films and scaffolds, and differentiated to monocyte-derived macrophages (MDM) for up to 28 days. The effect of surface structure on the MDM phenotype was assessed by assaying: cell attachment (DNA), activation (intracellular protein expression, esterase and acid phosphatase (AP) activity) as well as pro- and anti-inflammatory cytokines (TNF-α and IL-10, respectively). The cells on scaffolds exhibited an initial peak in total protein synthesized per DNA at 3 days; however, both substrates generated similar protein levels per DNA at all other time points. While scaffolds generated more esterase and AP per cell than for films, the cells on films expressed significantly more of these two proteins relative to their total protein produced. At day 7 (acute phase of monocyte activation), cells on films were significantly more activated than monocytes on the scaffolds as assessed by cell morphology and tumor necrosis factor-α and interleukin-10 levels. Histological analysis of scaffolds showed that cells were able to migrate throughout the three-dimensional matrix. By inducing a low inflammatory, high wound-healing phenotype monocyte, the negative effects of the foreign body reaction in vivo may be controlled in a manner possible to direct the vascular tissue cells into the appropriate functional phenotypes necessary for successful tissue engineering.
一种可降解的、具有极性的、疏水性的离子型聚氨酯（D-PHI），其物理性能可与周围动脉血管组织相媲美，用于研究单核细胞与两种不同物理形式的相互作用：二维薄膜和三维多孔支架。从人全血中分离出单核细胞，将其接种到 D-PHI 薄膜和支架上，并分化为单核细胞来源的巨噬细胞（MDM），培养时间长达 28 天。通过检测细胞黏附（DNA）、细胞激活（细胞内蛋白表达、酯酶和酸性磷酸酶（AP）活性）以及促炎和抗炎细胞因子（TNF-α和 IL-10），评估表面结构对 MDM 表型的影响。支架上的细胞在第 3 天表现出总蛋白合成量与 DNA 比值的初始峰值；然而，两种底物在所有其他时间点的 DNA 蛋白比值都相似。虽然支架上的细胞产生的酯酶和 AP 比薄膜上的细胞多，但薄膜上的细胞表达的这两种蛋白相对其总蛋白产量显著更高。在第 7 天（单核细胞激活的急性期），通过细胞形态和肿瘤坏死因子-α和白细胞介素-10 水平评估，薄膜上的细胞比支架上的单核细胞激活程度更高。支架的组织学分析表明，细胞能够在三维基质中迁移。通过诱导低炎症、高愈合表型的单核细胞，可以控制体内异物反应的负面影响，从而有可能引导血管组织细胞进入成功组织工程所需的适当功能表型。
