Thompson G J, Puleo D A
Center for Biomedical Engineering, University of Kentucky, Lexington 40506-0070, USA.
J Appl Biomater. 1995 Winter;6(4):249-58. doi: 10.1002/jab.770060406.
Ions released from implant surfaces are suspected of playing some role in osteolysis surrounding metal prostheses. To understand how ions may affect osteogenesis, previous work exposed osteogenic cells to metal ions to study acute cytotoxic responses. The purpose of this study was to assess the long-term effects of sublethal ion concentrations on osteogenic cell proliferation and function. Bone marrow stromal cells were harvested from juvenile rats and exposed to solutions of ions associated with Co-Cr-Mo and Ti-6Al-4V implants. Cells were cultured for up to 4 weeks and assayed for total protein, alkaline phosphatase, osteocalcin, and calcium. Other than V+5, none of the ions affected cell proliferation, indicating that the chosen concentrations were sublethal as desired. V+5 elicited delayed gross toxicity not previously observed during acute experiments. At the chosen concentrations, Co+2, Cr+6, Mo+6, and Co-Cr-Mo alloy elicited little effect on cell proliferation and moderate effects on matrix mineralization. Cultures exposed to Ti+4, Al+3, and Ti-6Al-4V alloy also showed no decrease in cell number, but did show near total suppression of osteocalcin secretion and matrix mineralization. These results suggest that ions released from Ti alloy implants may interfere with osteoblastic cell differentiation, contributing to periprosthetic osteolysis by impairing normal osteogenesis.
植入物表面释放的离子被怀疑在金属假体周围的骨溶解中起一定作用。为了解离子如何影响骨生成，先前的研究将成骨细胞暴露于金属离子中以研究急性细胞毒性反应。本研究的目的是评估亚致死浓度离子对成骨细胞增殖和功能的长期影响。从幼年大鼠中采集骨髓基质细胞，并将其暴露于与钴铬钼合金和钛6铝4钒合金植入物相关的离子溶液中。细胞培养长达4周，并检测总蛋白、碱性磷酸酶、骨钙素和钙。除了五价钒离子外，其他离子均未影响细胞增殖，这表明所选浓度如预期的那样是亚致死的。五价钒离子引发了延迟的严重毒性，这在急性实验中未曾观察到。在所选浓度下，二价钴离子、六价铬离子、六价钼离子和钴铬钼合金对细胞增殖影响不大，对基质矿化有中等程度的影响。暴露于四价钛离子、三价铝离子和钛6铝4钒合金的培养物中细胞数量也没有减少，但骨钙素分泌和基质矿化几乎完全受到抑制。这些结果表明，钛合金植入物释放的离子可能会干扰成骨细胞的分化，通过损害正常的骨生成导致假体周围骨溶解。
