Kohno Yusuke, Lin Tzuhua, Pajarinen Jukka, Jämsen Eemeli, Romero-Lopez Monica, Maruyama Masahiro, Lo Chi-Wen, Ueno Masaya, Nathan Karthik, Yao Zhenyu, Goodman Stuart B
Department of Orthopaedic Surgery, Stanford University, Stanford, California 94063, United States.
Department of Medicine, Clinicum, University of Helsinki and Helsinki University Hospital, Helsinki 00029, Finland.
ACS Biomater Sci Eng. 2019 Jun 10;5(6):3032-3038. doi: 10.1021/acsbiomaterials.9b00560. Epub 2019 May 1.
Titanium and titanium-based alloys are widely used in orthopaedic implants. Total joint replacement is very successful; however, the foreign body response and chronic inflammation caused by implant-derived biomaterial debris still remain as unsolved issues. Aseptic loosening accompanied by wear debris-induced osteolysis (bone loss) is one of the most frequent causes for late failure and revision surgery. Mesenchymal stem cells (MSCs) and IL-4 may be possible treatment strategies because of their immunomodulatory properties. We investigated the efficacy of novel MSC-based treatments on immunomodulation and osteogenic differentiation in an innovative cell coculture model of titanium particle-induced inflammation in the periprosthetic tissues. MSCs and macrophages were collected from the bone marrow of Balb/c mice. Both MSCs and macrophages (representing endogenous cells at the periprosthetic tissue) were seeded on the bottom wells of the 24-well transwell plates. We generated genetically modified NF-B sensing IL-4 secreting MSCs (inflammatory responsive MSCs) and MSCs preconditioned by lipopolysaccharide and TNF- to further enhance their immunomodulatory function. These modified MSCs (representing exogenous therapeutic cells implanted to the periprosthetic tissue) were seeded on the upper chambers of the transwell plates. These cocultures were then exposed to titanium particles for 7 days. NF-B sensing IL-4 secreting MSCs showed strong immunomodulation (significantly reduced TNF- and induced Arg1 expression) and promoted early osteogenesis (significantly induced Runx2, ALP, and -catenin as well as reduced Smurf2 expression) at day 7. IL-4 secreting MSCs also decreased TNF- protein secretion as early as day 3 and increased IL-1ra protein secretion at day 7, suggesting efficacious immunomodulation of particle-induced inflammation. Preconditioned MSCs did not show significant immunomodulation in this short-term experiment, but ALP and -catenin expression were significantly induced at day 7. Our results suggest that genetically modified IL-4 secreting MSCs and preconditioned MSCs have the potential to optimize bone regeneration in inflammatory conditions including periprosthetic osteolysis.
钛及钛基合金广泛应用于骨科植入物。全关节置换非常成功；然而，由植入物衍生的生物材料碎片引起的异物反应和慢性炎症仍然是未解决的问题。伴有磨损碎片诱导的骨溶解（骨质流失）的无菌性松动是晚期失败和翻修手术最常见的原因之一。间充质干细胞（MSCs）和白细胞介素-4（IL-4）因其免疫调节特性可能是可行的治疗策略。我们在一种创新的细胞共培养模型中研究了新型基于间充质干细胞的治疗方法对钛颗粒诱导的假体周围组织炎症的免疫调节和成骨分化的疗效。间充质干细胞和巨噬细胞从Balb/c小鼠的骨髓中收集。间充质干细胞和巨噬细胞（代表假体周围组织中的内源性细胞）都接种在24孔Transwell板的底部孔中。我们生成了基因修饰的能感应核因子-κB（NF-κB）并分泌IL-4的间充质干细胞（炎症反应性间充质干细胞）以及用脂多糖和肿瘤坏死因子-α（TNF-α）预处理的间充质干细胞，以进一步增强它们的免疫调节功能。这些经过修饰的间充质干细胞（代表植入到假体周围组织的外源性治疗细胞）接种在Transwell板的上室。然后将这些共培养物暴露于钛颗粒7天。能感应NF-κB并分泌IL-4的间充质干细胞在第7天表现出强大的免疫调节作用（显著降低TNF-α并诱导精氨酸酶1（Arg1）表达）并促进早期成骨（显著诱导Runx2、碱性磷酸酶（ALP）和β-连环蛋白以及降低Smurf2表达）。分泌IL-4的间充质干细胞早在第3天就减少了TNF-α蛋白分泌，并在第7天增加了白细胞介素-1受体拮抗剂（IL-1ra）蛋白分泌，表明对颗粒诱导的炎症有有效的免疫调节作用。在这个短期实验中，预处理的间充质干细胞没有显示出显著的免疫调节作用，但在第7天ALP和β-连环蛋白表达被显著诱导。我们的结果表明，基因修饰的分泌IL-4的间充质干细胞和预处理的间充质干细胞有潜力在包括假体周围骨溶解在内的炎症条件下优化骨再生。
