Laboratory for Biomaterials and Bioengineering, CRC-Tier I, Dept Min-Met-Materials Eng and Regenerative Medicine, CHU de Québec, Laval University, Quebec City, Canada.
genT_LΛB, Department of Chemistry, Materials and Chemical Engineering 'G. Natta', Politecnico di Milano, Milan, Italy.
Biomed Mater. 2023 Oct 19;18(6). doi: 10.1088/1748-605X/acfd77.
Human tissues are characterized by complex composition and cellular and extracellular matrix (ECM) organization at microscopic level. In most of human tissues, cells and ECM show an anisotropic arrangement, which confers them specific properties., the ability to closely mimic this complexity is limited. However, in the last years, extrusion bioprinting showed a certain potential for aligning cells and biomolecules, due to the application of shear stress during the bio-fabrication process. In this work, we propose a strategy to combine collagen (col) with tyramine-modified hyaluronic acid (THA) to obtain a printable col-THA bioink for extrusion bioprinting, solely-based on natural-derived components. Collagen fibers formation within the hybrid hydrogel, as well as collagen distribution and spatial organization before and after printing, were studied. For the validation of the biological outcome, fibroblasts were selected as cellular model and embedded in the col-THA matrix. Cell metabolic activity and cell viability, as well as cell distribution and alignment, were studied in the bioink before and after bioprinting. Results demonstrated successful collagen fibers formation within the bioink, as well as collagen anisotropic alignment along the printing direction. Furthermore, results revealed suitable biological properties, with a slightly reduced metabolic activity at day 1, fully recovered within the first 3 d post-cell embedding. Finally, results showed fibroblasts elongation and alignment along the bioprinting direction. Altogether, results validated the potential to obtain collagen-based bioprinted constructs, with both cellular and ECM anisotropy, without detrimental effects of the fabrication process on the biological outcome. This bioink can be potentially used for a wide range of applications in tissue engineering and regenerative medicine in which anisotropy is required.
人体组织的特点是微观水平上的复杂组成、细胞和细胞外基质（ECM）组织。在大多数人体组织中，细胞和 ECM 呈现各向异性排列，赋予它们特定的性质。然而，到目前为止，能够紧密模拟这种复杂性的方法仍然有限。然而，在过去的几年中，挤出式生物打印由于在生物制造过程中应用了剪切应力，显示出了对细胞和生物分子进行排列的潜力。在这项工作中，我们提出了一种策略，即将胶原蛋白（col）与经过-tyramine 修饰的透明质酸（THA）结合，获得一种可用于挤出式生物打印的、仅基于天然衍生成分的 col-THA 生物墨水。研究了混合水凝胶中胶原蛋白纤维的形成，以及打印前后胶原蛋白的分布和空间组织。为了验证生物结果，选择成纤维细胞作为细胞模型并嵌入 col-THA 基质中。研究了生物墨水在生物打印前后细胞代谢活性和细胞活力以及细胞分布和排列。结果表明，生物墨水中成功地形成了胶原蛋白纤维，并且胶原蛋白沿着打印方向呈现各向异性排列。此外，结果表明具有合适的生物学特性，在细胞包埋后的第 1 天代谢活性略有降低，但在第 3 天内完全恢复。最后，结果显示成纤维细胞沿着生物打印方向伸长和排列。总之，结果验证了获得具有细胞和 ECM 各向异性的基于胶原蛋白的生物打印构建体的潜力，而不会对生物结果产生制造过程的不利影响。这种生物墨水可潜在地用于组织工程和再生医学中需要各向异性的广泛应用。
