Dapunt Ulrike, Prior Birgit, Kretzer Jan Philippe, Hänsch Gertrud Maria, Gaida Matthias Martin
Center for Orthopaedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Schlierbacher Landstrasse, Heidelberg, Germany.
Department of Anesthesiology, Heidelberg University Hospital, Heidelberg.
Int J Med Sci. 2021 Jan 1;18(2):295-303. doi: 10.7150/ijms.50270. eCollection 2021.
Implant loosening - either infectious or aseptic- is a still a major complication in the field of orthopaedic surgery. In both cases, a pro-inflammatory peri-prosthetic environment is generated by the immune system - either triggered by bacteria or by implant wear particles - which leads to osteoclast differentiation and osteolysis. Since infectious cases in particular often require multiple revision surgeries, we wondered whether commonly used surgical suture material may also activate the immune system and thus contribute to loss of bone substance by generation of osteoclasts. Tissue samples from patients suffering from infectious implant loosening were collected intraoperatively and presence of osteoclasts was evaluated by histopathology and immunohistochemistry. Further on, human monocytes were isolated from peripheral blood and stimulated with surgical suture material. Cell supernatant samples were collected and ELISA analysis for the pro-inflammatory cytokine IL-8 was performed. These experiments were additionally carried out on ivory slices to demonstrate functionality of osteoclasts. Whole blood samples were incubated with surgical suture material and up-regulation of activation-associated cell surface markers CD11b and CD66b on neutrophils was evaluated by flow cytofluorometry analysis. We were able to demonstrate that multinucleated giant cells form in direct vicinity to surgical suture material. These cells stained positive for cathepsin K, which is a typical protease found in osteoclasts. By analysis, we were able to show that monocytes differentiated into osteoclasts when stimulated with surgical suture material. Resorption pits on ivory slices provided proof that the osteoclasts were functional. Release of IL-8 into cell supernatant was increased after stimulation with suture material and was further enhanced if minor amounts of bacterial lipoteichoic acid (LTA) were added. Neutrophils were also activated by surgical suture material and up-regulation of CD11b and CD66b could be seen. We were able to demonstrate that surgical suture material induces a pro-inflammatory response of immune cells which leads to osteoclast differentiation, in particular in combination with bacterial infection. In conclusion, surgical suture material -aside from bacteria and implant wear particles- is a contributing factor in implant loosening.
植入物松动，无论是感染性的还是无菌性的，仍然是骨科手术领域的一个主要并发症。在这两种情况下，免疫系统都会产生一种促炎性假体周围环境，这要么是由细菌引发，要么是由植入物磨损颗粒引发，进而导致破骨细胞分化和骨溶解。由于特别是感染性病例通常需要多次翻修手术，我们想知道常用的手术缝合材料是否也会激活免疫系统，从而通过破骨细胞的生成导致骨质流失。术中收集了感染性植入物松动患者的组织样本，并通过组织病理学和免疫组织化学评估破骨细胞的存在情况。此外，从外周血中分离出人类单核细胞，并用手术缝合材料进行刺激。收集细胞上清液样本，并进行促炎性细胞因子白细胞介素 - 8（IL - 8）的酶联免疫吸附测定（ELISA）分析。这些实验还在象牙切片上进行，以证明破骨细胞的功能。将全血样本与手术缝合材料一起孵育，并通过流式细胞荧光分析评估中性粒细胞上激活相关细胞表面标志物CD11b和CD66b的上调情况。我们能够证明在手术缝合材料的直接附近形成了多核巨细胞。这些细胞组织蛋白酶K染色呈阳性，组织蛋白酶K是破骨细胞中发现的一种典型蛋白酶。通过分析，我们能够表明单核细胞在用手术缝合材料刺激时会分化为破骨细胞。象牙切片上的吸收凹坑证明破骨细胞具有功能。用缝合材料刺激后，IL - 8释放到细胞上清液中的量增加，如果添加少量细菌脂磷壁酸（LTA），则会进一步增加。手术缝合材料也会激活中性粒细胞，并且可以看到CD11b和CD66b的上调。我们能够证明手术缝合材料会诱导免疫细胞的促炎性反应，这会导致破骨细胞分化，特别是在与细菌感染共同作用时。总之，除了细菌和植入物磨损颗粒外，手术缝合材料也是植入物松动的一个促成因素。
