Krüger-Genge Anne, Hauser Sandra, Neffe Axel T, Liu Yue, Lendlein Andreas, Pietzsch Jens, Jung Friedrich
Institute of Active Polymers and Berlin-Brandenburg Centre for Regenerative Therapies (BCRT), Helmholtz-Zentrum Geesthacht, Kantstr. 55, 14513 Teltow, Germany.
Department of Radiopharmaceutical and Chemical Biology, Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstrasse 400, 01328 Dresden, Germany.
ACS Biomater Sci Eng. 2021 Feb 8;7(2):527-540. doi: 10.1021/acsbiomaterials.0c01432. Epub 2021 Jan 26.
The establishment of confluent endothelial cell (EC) monolayers on implanted materials has been identified as a concept to avoid thrombus formation but is a continuous challenge in cardiovascular device engineering. Here, material properties of gelatin-based hydrogels obtained by reacting gelatin with varying amounts of lysine diisocyanate ethyl ester were correlated with the functional state of hydrogel contacting venous EC (HUVEC) and HUVEC's ability to form a monolayer on these hydrogels. The density of adherent HUVEC on the softest hydrogel at 37 °C (' = 1.02 kPa, = 1.1 ± 0.3 kPa) was significantly lower (125 mm) than on the stiffer hydrogels (920 mm; ' = 2.515 and 5.02 kPa, = 4.8 ± 0.8 and 10.3 ± 1.2 kPa). This was accompanied by increased matrix metalloprotease activity (9 pmol·min compared to 0.6 pmol·min) and stress fiber formation, while cell-to-cell contacts were comparable. Likewise, release of eicosanoids (e.g., prostacyclin release of 1.7 vs 0.2 pg·mL·cell) and the pro-inflammatory cytokine MCP-1 (8 vs <1.5 pg·mL·cell) was higher on the softer than on the stiffer hydrogels. The expressions of pro-inflammatory markers COX-2, COX-1, and RAGE were slightly increased on all hydrogels on day 2 (up to 200% of the control), indicating a weak inflammation; however, the levels dropped to below the control from day 6. The study revealed that hydrogels with higher moduli approached the status of a functionally confluent HUVEC monolayer. The results indicate the promising potential especially of the discussed gelatin-based hydrogels with higher ' as biomaterials for implants foreseen for the venous system.
在植入材料上建立融合的内皮细胞（EC）单层已被视为一种避免血栓形成的理念，但在心血管设备工程中仍是一项持续的挑战。在此，通过使明胶与不同量的赖氨酸二异氰酸酯乙酯反应获得的明胶基水凝胶的材料特性，与水凝胶接触静脉内皮细胞（HUVEC）的功能状态以及HUVEC在这些水凝胶上形成单层的能力相关。在37°C时，最软的水凝胶（' = 1.02 kPa， = 1.1±0.3 kPa）上贴壁的HUVEC密度（125个/mm）显著低于较硬的水凝胶（920个/mm；' = 2.515和5.02 kPa， = 4.8±0.8和10.3±1.2 kPa）。这伴随着基质金属蛋白酶活性增加（9 pmol·min，而对照组为0.6 pmol·min）和应力纤维形成，而细胞间接触相当。同样，较软水凝胶上类花生酸（例如，前列环素释放量为1.7 vs 0.2 pg·mL·细胞）和促炎细胞因子MCP-1（8 vs <1.5 pg·mL·细胞）的释放高于较硬水凝胶。在第2天，所有水凝胶上促炎标志物COX-2、COX-1和RAGE的表达略有增加（高达对照的200%），表明有轻微炎症；然而，从第6天起水平降至对照以下。该研究表明，模量较高的水凝胶更接近功能融合的HUVEC单层状态。结果表明，特别是所讨论的具有较高'的明胶基水凝胶作为用于静脉系统植入物的生物材料具有广阔的应用前景。
