Osteochondral defects of articular cartilage cannot regenerate spontaneously. For its surgical treatment, advancements in cartilage tissue engineering have particularly focused on subchondral bone lesions that tend to delay healing. Therefore, it is important to understand interactions between subchondral bone and chondrocytes. This study aimed to investigate the behavior of chondrogenic ATDC5 cells on oriented hydroxyapatite (HAp) films that mimic bone surfaces. HAp nanoparticles prepared herein were needle like and plate like. HAp films were formed through self‐organization of the nanoparticles and had 2D structures regularly arrayed with the particles. Both films prominently comprised a‐plane orientation surfaces but differed in the degree of hydrophilicity because of the patterns of particle self‐assembly. ATDC5 cells cultured on the HAp film with plate‐like particles could adhered in a shorter period but could not spread. The adhesive force of cells was weaker with the hydrophilic surface than with other surfaces, as determined using a trypsin‐based cell detachment assay. In addition, ATDC5 cells displayed enhanced proliferation and chondrogenic differentiation. Our results suggest that the oriented HAp film formed using plate‐like particles provided chondrogenic cells with a desired scaffold as that of subchondral bone to increase cell proliferation and differentiation.

中文翻译：

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具有排列的板状颗粒的定向羟基磷灰石膜增强了 ATDC5 细胞的软骨分化。

关节软骨的骨软骨缺损不能自发再生。对于手术治疗，软骨组织工程的进步特别关注往往会延迟愈合的软骨下骨病变。因此，了解软骨下骨和软骨细胞之间的相互作用非常重要。本研究旨在研究软骨形成性 ATDC5 细胞在模拟骨表面的定向羟基磷灰石 (HAp) 膜上的行为。本文制备的HAp纳米颗粒呈针状和板状。HAp 膜是通过纳米粒子的自组织形成的，并且具有与粒子规则排列的二维结构。两种薄膜都主要包含 a 面取向表面，但由于颗粒自组装的模式，亲水性程度不同。ATDC5 细胞培养在具有板状颗粒的 HAp 膜上，可以在较短的时间内粘附但不能扩散。使用基于胰蛋白酶的细胞分离试验确定，细胞与亲水表面的粘附力比与其他表面的粘附力弱。此外，ATDC5 细胞显示出增强的增殖和软骨分化。我们的结果表明，使用板状颗粒形成的定向 HAp 膜为软骨细胞提供了所需的支架，如软骨下骨，以增加细胞增殖和分化。ATDC5 细胞显示出增强的增殖和软骨分化。我们的结果表明，使用板状颗粒形成的定向 HAp 膜为软骨细胞提供了所需的支架，如软骨下骨，以增加细胞增殖和分化。ATDC5 细胞显示出增强的增殖和软骨分化。我们的结果表明，使用板状颗粒形成的定向 HAp 膜为软骨细胞提供了所需的支架，如软骨下骨，以增加细胞增殖和分化。