探讨纯钛不同形貌表面对骨髓间充质干细胞（MSC）黏附、增殖、分化的影响。

制备抛光纯钛（MP）、纳米管（TNT）、喷砂酸蚀（SLA）表面，通过扫描电镜（SEM）观察试件表面形貌，激光扫描共聚焦显微镜测量表面粗糙度，表面接触角分析仪分析表面水接触角。通过免疫荧光染色观察不同钛表面MSC形态，细胞计数法检测细胞早期黏附数量，CCK-8法检测细胞增殖，碱性磷酸酶（ALP）检测试剂盒检测ALP活性。采用单因素方差分析进行统计分析，LSD-t检验进行两两比较。

TNT组表面见排列有序、管径约为80 nm的纳米管，SLA组呈微米-亚微米二级孔洞结构。SLA组表面粗糙度（Sa= 1.39 μm、Sq= 1.75 μm）最高，TNT组（Sa= 1.15 μm、Sq= 1.48 μm）其次，MP组（Sa= 0.87 μm、Sq= 1.14 μm）最低，差异有统计学意义（F_Sa=28.54、F_Sq=24.70，P<0.01）。TNT组表面接触角（8.11°）最小，亲水性最佳，差异有统计学意义（F= 16.32，P<0.01）。细胞免疫荧光染色显示MP组MSC呈方形，TNT组MSC呈长梭形，SLA组MSC呈多角形。TNT和SLA组接种30 min后的细胞黏附量（132.45、176.90个/视野）高于MP组（64.80个/视野），差异有统计学意义（F=12.05，P<0.01），接种60 min后各组间差异无统计学意义。CCK-8结果显示，接种1、7 d后各组间差异无统计学意义；接种3、5 d后，MP组细胞增殖活性最高，TNT组其次，SLA组最低，差异有统计学意义（F_{3 d}= 175.44，P_{3 d}<0.01；F_{5 d}=6.329，P_{5 d}= 0.02）。细胞分化结果显示，7、14 d TNT组ALP活性（ALP_{7 d}=156.34 U/gprot、ALP_{14 d}= 153.48 U/gprot）均显著高于MP（ALP_{7 d}= 68.21 U/gprot，ALP_{14 d}= 102.73 U/gprot）和SLA（ALP_{7 d}= 65.30 U/gprot、ALP_{14 d}= 86.53 U/gprot）两组，差异有统计学意义（F_{7 d}= 4.93，P_{7 d}= 0.04；F_{14 d}= 6.49，P_{14 d}= 0.02）。

与微米级SLA表面相比，纳米级TNT表面呈高度亲水性，并更利于MSC的黏附、增殖和骨向分化。

To study the influence of different titanium topographies on the adhesion, proliferation and differentiation of mesenchymal stem cells (MSCs) .

All the titanium discs were divided into three groups and accepted the following treatments: machined smooth Ti (MP) , sandblasted and acid etched Ti (SLA) , TiO₂ nanotubes (TNT) . The topography of Ti discs was observed by a scanning electron microscope (SEM) . The surface roughness of samples was determined using a laser scanning confocal microscope. The contact angles were measured using a contact angle analyzer. The morphology of MSC on different titanium surfaces was evaluated by immunofluorescence staining. Cell early adhesion was evaluated by counting the number of cells on different titanium surfaces. The cell counting kit-8 (CCK-8) assay was used to evaluate the proliferation activity. Alkaline phosphatase (ALP) activity was measured using an ALP kit. The level of significance was determined by One-Way ANOVA followed by LSD-t test for a multiple comparison procedure.

Evenly distributed nanotubes were observed in TNT with a diameter of about 80 nm, while a hierarchical structure with pores and holes was found in SLA. The roughness of SLA (Sa= 1.39 μm, Sq= 1.75 μm) was the highest, followed by TNT (Sa= 1.15 μm, Sq= 1.48 μm) and MP (Sa= 0.87 μm, Sq= 1.14 μm) (F_Sa= 28.54, F_Sq= 24.70, P<0.01) . The contact angle of TNT (8.11°) was the lowest among the three groups (F= 16.32, P<0.01) , indicating the highest hydrophilicity. With the immunofluorescence staining, cells were observed as cuboidal on MP, polygon-like on SLA and spindle-like on TNT. At the first 30 min of culture, more cell attachment was found on TNT and SLA (132.45/field, 176.90/field) than that on MP (64.80/field) (F=12.05, P<0.01) , while there was no significant difference among groups at 60 min of culture. According to the result of CCK-8 assay, there was no significant difference in the proliferation of cells among groups on day 1 and 7; whereas on day 3 and 5, the proliferation level of cells on MP was the highest, followed by TNT and SLA (F_{3 d}= 175.44, P_{3 d}<0.01; F_{5 d}= 6.329, P_{5 d}= 0.02) . A significantly higher ALP activity was detected in TNT (ALP_{7 d}= 156.34 U/gprot, ALP_{14 d}= 153.48 U/gprot) , compared with MP (ALP_{7 d}= 68.21 U/gprot, ALP_{14 d}= 102.73 U/gprot) and SLA (ALP_{7 d}= 65.30 U/gprot, ALP_{14 d}= 86.53 U/gprot) (F_{7 d}= 4.93, P_{7 d}= 0.04; F_{14 d}= 6.49, P_{14 d}= 0.02) .

The surface of TNT presents to be highly hydrophilic and is more favorable for the adhesion, proliferation and differentiation of MSC compared with SLA.