Department of Orthopaedic Surgery, Stanford University, Stanford, CA, USA.
Clin Orthop Relat Res. 2011 Jan;469(1):113-22. doi: 10.1007/s11999-010-1645-5.
Aseptic loosening and periprosthetic osteolysis resulting from wear debris are major complications of total joint arthroplasty. Monocyte/macrophages are the key cells related to osteolysis at the bone-implant interface of joint arthroplasties. Whether the monocyte/macrophages found at the implant interface in the presence of polyethylene particles are locally or systemically derived is unknown.
QUESTIONS/PURPOSES: We therefore asked (1) whether macrophages associated with polyethylene particle-induced chronic inflammation are recruited locally or systemically and (2) whether the recruited macrophages are associated with enhanced osteolysis locally.
Noninvasive in vivo imaging techniques (bioluminescence and microCT) were used to investigate initial macrophage migration systemically from a remote injection site to polyethylene wear particles continuously infused into the femoral canal. We used histologic and immunohistologic staining to confirm localization of migrated macrophages to the polyethylene particle-treated femoral canals and monitor cellular markers of bone remodeling.
The values for bioluminescence were increased for animals receiving UHMWPE particles compared with the group in which the carrier saline was infused. At Day 8, the ratio of bioluminescence (operated femur divided by nonoperated contralateral femur of each animal) for the UHMWPE group was 13.95 ± 5.65, whereas the ratio for the saline group was 2.60 ± 1.14. Immunohistologic analysis demonstrated the presence of reporter macrophages in the UHMWPE particle-implanted femora only. MicroCT scans showed the bone mineral density for the group with both UHMWPE particles and macrophage was lower than the control groups.
Infusion of clinically relevant polyethylene particles, similar to the human scenario, stimulated systemic migration of remotely injected macrophages and local net bone resorption.
磨损颗粒导致的无菌性松动和假体周围骨溶解是全关节置换术的主要并发症。单核细胞/巨噬细胞是与关节置换假体界面骨溶解相关的关键细胞。在聚乙烯颗粒存在的情况下，在植入物界面发现的单核细胞/巨噬细胞是局部还是全身来源尚不清楚。
问题/目的：因此，我们提出了以下两个问题：（1）与聚乙烯颗粒诱导的慢性炎症相关的巨噬细胞是局部募集还是全身募集；（2）募集的巨噬细胞是否与局部骨溶解增强有关。
非侵入性体内成像技术（生物发光和 microCT）用于研究初始巨噬细胞从远程注射部位系统性迁移到连续输注到股骨髓腔内的聚乙烯磨损颗粒。我们使用组织学和免疫组织化学染色来确认迁移的巨噬细胞定位于聚乙烯颗粒处理的股骨髓腔，并监测骨重塑的细胞标记物。
与接受 UHMWPE 颗粒的动物相比，接受载体盐水输注的动物的生物发光值增加。在第 8 天，UHMWPE 组的生物发光比值（每个动物的手术股骨除以非手术对侧股骨）为 13.95 ± 5.65，而盐水组的比值为 2.60 ± 1.14。免疫组织化学分析仅显示在 UHMWPE 颗粒植入股骨中存在报告巨噬细胞。microCT 扫描显示，同时存在 UHMWPE 颗粒和巨噬细胞的组的骨矿物质密度低于对照组。
临床相关聚乙烯颗粒的输注，类似于人类情况，刺激了远程注射的巨噬细胞的系统性迁移和局部净骨吸收。
