Wilson College of Textiles, North Carolina State University, Raleigh, North Carolina, USA.
Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
J Biomed Mater Res B Appl Biomater. 2022 Dec;110(12):2624-2635. doi: 10.1002/jbm.b.35116. Epub 2022 Jul 2.
A rotator cuff tendon tear is a common shoulder injury with a relatively high rate of recurrence after surgical repair. In order to reinforce the repair and reduce the risk of clinical complications, a patch scaffold is typically sutured over the tendon tear to provide post-surgical mechanical support. However, despite considerable research effort in this area, a patch scaffold that provides both superior initial mechanical properties and supports cell proliferation at the same time has not yet been achieved. In this study, we engineered a collagen/poly(lactic acid) (COL/PLA) hybrid yarn to leverage mechanical strength of PLA yarn and the bioactivity of collagen. The COL/PLA yarns were used to fabricate a tissue engineering scaffold using textile weaving technology. This hybrid scaffold had a tensile strength of 354.0 ± 36.0 N under dry conditions and 267.2 ± 15.9 N under wet conditions, which was satisfactory to maintain normal tendon function. By introducing COL yarns into the hybrid scaffold, the proliferation of tendon-derived cells was significantly improved on the scaffold. Cell coverage after 28-days of in vitro cell culture was noticeably higher on the COL yarns compared to the PLA yarns as a result of a larger number of cells and more spread cell morphology on collagen. Cells spread in multiple directions on COL yarns, which resembled a more natural cell attachment on extracellular matrix. On the contrary, the cells attached to the PLA filaments presented an elongated morphology along the fiber's axial direction. Combining the mechanical robustness of PLA and the biological activity of collagen, the woven COL/PLA hybrid scaffold has shown its potential to be a promising candidate for tendon repair applications.
肩袖肌腱撕裂是一种常见的肩部损伤，手术后修复的复发率相对较高。为了加强修复并降低临床并发症的风险，通常会在肌腱撕裂处缝合补片支架，以提供术后机械支撑。然而，尽管在该领域进行了相当多的研究，但仍未实现一种既能提供优越的初始机械性能，又能支持细胞增殖的补片支架。在这项研究中，我们设计了一种胶原/聚乳酸（COL/PLA）混合纱线，以利用 PLA 纱线的机械强度和胶原的生物活性。使用 COL/PLA 纱线通过纺织编织技术制造了组织工程支架。该混合支架在干燥条件下的拉伸强度为 354.0±36.0 N，在潮湿条件下的拉伸强度为 267.2±15.9 N，足以维持正常的肌腱功能。通过在混合支架中引入 COL 纱线，显著提高了肌腱衍生细胞在支架上的增殖能力。与 PLA 纱线相比，COL 纱线上的细胞覆盖率在体外细胞培养 28 天后明显更高，这是由于 COL 纱线上的细胞数量更多，且细胞形态更舒展。细胞在 COL 纱线上呈多个方向伸展，这类似于细胞在细胞外基质上更自然的附着方式。相反，附着在 PLA 纤维上的细胞呈现出沿纤维轴向的细长形态。结合 PLA 的机械强度和胶原的生物活性，编织的 COL/PLA 混合支架显示出作为肌腱修复应用的有前途的候选材料的潜力。
