Schoenenberger Angelina D, Schipanski Angela, Malheiro Vera, Kucki Melanie, Snedeker Jess G, Wick Peter, Maniura-Weber Katharina
Department of Orthopaedics, Balgrist Hospital, University of Zurich, Zurich, Switzerland.
Institute for Biomechanics, ETH, Swiss Federal Institute of Technology, Zurich, Switzerland.
ACS Biomater Sci Eng. 2016 Jun 13;2(6):908-919. doi: 10.1021/acsbiomaterials.6b00006. Epub 2016 May 10.
Wear particles of total joint replacements may lead to an inflammatory response driven by cells of the monocyte/macrophage lineage. Today, there is a general agreement that the continuous release of wear particles by the implant has a critical impact on periprosthetic osteolysis, which can eventually lead to aseptic loosening of the implant. The focus of this study lay on the determination of the polarization of macrophages (M0) toward the pro-inflammatory M1 phenotype or the anti-inflammatory M2-like phenotype upon exposure to differently sized TiO particles. The analysis was done with an in vitro model using THP-1 monocytes. It offers a direct characterization of the polarization profile of the macrophages exposed to nano- (<100 nm, measured hydrodynamic diameter: 518.5 nm) and micro- (<5 μm, measured hydrodynamic diameter: 2213 nm) sized TiO particles in different concentrations (4 × 10 -4 × 10 particles/mL). The polarization profile was analyzed by the quantitative assessment of relative gene expression levels as well as by the determination of specific proteins by enzyme linked immunosorbent assay (ELISA). Analysis by qRT-PCR revealed significantly elevated levels of pro-inflammatory markers such as TNF-α and CD197 at the highest concentration of stimulation by the microsized particles. This was confirmed on the protein level in the cytokine expression profile of TNF-α. Furthermore, no significant differences were found for the markers CCL22 and CD206, which are specific for the M2-like phenotype. In contrast, stimulation by nanoparticles did not induce macrophage polarization toward M1 or M2-like phenotype in any applied concentration. We conclude that the size of the particle is a determinant factor in driving the biological response of macrophages and an increased understanding of this relationship may potentially guide the design of new biomaterials.
全关节置换的磨损颗粒可能会引发由单核细胞/巨噬细胞谱系细胞驱动的炎症反应。如今，人们普遍认为植入物持续释放磨损颗粒对假体周围骨溶解具有关键影响，最终可能导致植入物无菌性松动。本研究的重点在于确定巨噬细胞（M0）在暴露于不同尺寸的TiO颗粒后向促炎性M1表型或抗炎性M2样表型的极化情况。分析是使用THP-1单核细胞的体外模型进行的。它直接表征了暴露于不同浓度（4×10 - 4×10颗粒/毫升）的纳米级（<100纳米，测量的流体动力学直径：518.5纳米）和微米级（<5微米，测量的流体动力学直径：2213纳米）TiO颗粒的巨噬细胞的极化情况。通过对相对基因表达水平的定量评估以及通过酶联免疫吸附测定（ELISA）确定特定蛋白质来分析极化情况。qRT-PCR分析显示，在微米级颗粒最高刺激浓度下，促炎性标志物如TNF-α和CD197的水平显著升高。这在TNF-α细胞因子表达谱的蛋白质水平上得到了证实。此外，对于M2样表型特异的标志物CCL22和CD206，未发现显著差异。相比之下，在任何应用浓度下，纳米颗粒刺激均未诱导巨噬细胞向M1或M2样表型极化。我们得出结论，颗粒大小是驱动巨噬细胞生物学反应的决定性因素，对这种关系的进一步理解可能会指导新型生物材料的设计。
