da Silva Domingues Joana F, Roest Steven, Wang Yi, van der Mei Henny C, Libera Matthew, van Kooten Theo G, Busscher Henk J
University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, P.O. Box 196, 9700 AD Groningen, The Netherlands.
Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ, USA.
Acta Biomater. 2015 May;18:1-8. doi: 10.1016/j.actbio.2015.02.028. Epub 2015 Mar 6.
Biomaterial-associated-infection causes failure of biomaterial implants. Many new biomaterials have been evaluated for their ability to inhibit bacterial colonization and stimulate tissue-cell-integration, but neglect the role of immune cells. This paper compares macrophage phagocytosis of adhering Staphylococcus aureus on cationic-coatings and patterned poly(ethylene)glycol-hydrogels versus common biomaterials and stainless steel in order to identify surface conditions that promote clearance of adhering bacteria. Staphylococci were allowed to adhere and grow on the materials in a parallel-plate-flow-chamber, after which murine macrophages were introduced. From the decrease in the number of adhering staphylococci, phagocytosis-rates were calculated, and total macrophage displacements during an experiment determined. Hydrophilic surfaces had the lowest phagocytosis-rates, while common biomaterials had intermediate phagocytosis-rates. Patterning of poly(ethylene)glycol-hydrogel coatings increased phagocytosis-rates to the level of common biomaterials, while on cationic-coatings phagocytosis-rates remained relatively low. Likely, phagocytosis-rates on cationic coatings are hampered relative to common biomaterials through strong electrostatic binding of negatively-charged macrophages and staphylococci. On polymeric biomaterials and glass, phagocytosis-rates increased with macrophage displacement, while both parameters increased with biomaterial surface hydrophobicity. Thus hydrophobicity is a necessary surface condition for effective phagocytosis. Concluding, next-generation biomaterials should account for surface effects on phagocytosis in order to enhance the ability of these materials to resist biomaterial-associated-infection.
生物材料相关感染会导致生物材料植入物失效。许多新型生物材料已被评估其抑制细菌定植和刺激组织 - 细胞整合的能力，但却忽视了免疫细胞的作用。本文比较了阳离子涂层和图案化聚乙二醇水凝胶上附着的金黄色葡萄球菌与普通生物材料和不锈钢上巨噬细胞的吞噬作用，以确定促进清除附着细菌的表面条件。使葡萄球菌在平行板流动室中的材料上附着并生长，之后引入小鼠巨噬细胞。根据附着葡萄球菌数量的减少计算吞噬率，并确定实验过程中巨噬细胞的总位移。亲水表面的吞噬率最低，而普通生物材料的吞噬率处于中间水平。聚乙二醇水凝胶涂层的图案化使吞噬率提高到普通生物材料的水平，而阳离子涂层上的吞噬率仍然相对较低。可能是由于带负电荷的巨噬细胞和葡萄球菌之间的强静电结合，阳离子涂层上的吞噬率相对于普通生物材料受到阻碍。在聚合物生物材料和玻璃上，吞噬率随着巨噬细胞位移而增加，而这两个参数都随着生物材料表面疏水性的增加而增加。因此，疏水性是有效吞噬的必要表面条件。总之，下一代生物材料应考虑表面对吞噬作用的影响，以增强这些材料抵抗生物材料相关感染的能力。
