Abstract A superelastic Ni-free Ti–27Nb alloy has been synthesized and gas nitrided at high temperature to investigate its suitability for vascular implant applications. The cellular responses of human endothelial progenitor cells (EPCs) to both bare and nitrided Ti–27Nb alloy have been analyzed using Live/Dead staining, MTT assay, fluorescence microscopy and ELISA technique, as well as NiTi alloy for comparison. Live/Dead staining and MTT assay were performed to assess the cellular viability and proliferation, while fluorescence microscopy was used to analyze cell adhesion, cell morphology, and the expression of endothelial cell markers (VE-cadherin and von Willebrand factor). Secretion of the pro-inflammatory chemokine MCP (monocyte chemoattractant protein)-1 by the cells grown in contact with the analyzed materials was further verified using the enzyme-linked immunosorbent assay. The results obtained revealed that adhesion, spreading, viability, proliferation rate and phenotypic markers expression of EPCs were similar on the surfaces of Ti–27Nb and NiTi alloys. Cells exposed to nitrided Ti–27Nb surface exhibited significantly decreased inflammatory response, which may be beneficial for reducing in-stent restenosis incidence.

中文翻译：

---

氮化无 Ni Ti-27Nb 合金对人内皮祖细胞行为的体外研究

摘要 合成了一种超弹性无 Ni Ti-27Nb 合金并在高温下进行气体氮化，以研究其在血管植入物应用中的适用性。已经使用活/死染色、MTT 测定、荧光显微镜和 ELISA 技术以及 NiTi 合金分析了人内皮祖细胞 (EPC) 对裸露和氮化 Ti-27Nb 合金的细胞反应。进行活/死染色和 MTT 测定以评估细胞活力和增殖，而荧光显微镜用于分析细胞粘附、细胞形态和内皮细胞标志物（VE-钙粘蛋白和冯维勒布兰德因子）的表达。使用酶联免疫吸附试验进一步验证了与分析材料接触生长的细胞分泌促炎趋化因子 MCP（单核细胞趋化蛋白）-1。获得的结果表明，EPCs 在 Ti-27Nb 和 NiTi 合金表面的粘附、扩散、活力、增殖率和表型标记表达相似。暴露于氮化 Ti-27Nb 表面的细胞表现出显着降低的炎症反应，这可能有利于降低支架内再狭窄的发生率。