Schaefer Natascha, Andrade Mier Mateo S, Sonnleitner David, Murenu Nicoletta, Ng Xuen Jen, Lamberger Zan, Buechner Margitta, Trossmann Vanessa T, Schubert Dirk W, Scheibel Thomas, Lang Gregor
Institute for Clinical Neurobiology, University Hospital of Würzburg, Versbacherstr. 5, D-97078, Würzburg, Germany.
Biopolymer Processing Group, University of Bayreuth, Ludwig-Thoma-Str. 36A, D-95447, Bayreuth, Germany.
Small Methods. 2023 Oct;7(10):e2201717. doi: 10.1002/smtd.202201717. Epub 2023 Jun 22.
The development of bio-inks capable of being 3D-printed into cell-containing bio-fabricates with sufficient shape fidelity is highly demanding. Structural integrity and favorable mechanical properties can be achieved by applying high polymer concentrations in hydrogels. Unfortunately, this often comes at the expense of cell performance since cells may become entrapped in the dense matrix. This drawback can be addressed by incorporating fibers as reinforcing fillers that strengthen the overall bio-ink structure and provide a second hierarchical micro-structure to which cells can adhere and align, resulting in enhanced cell activity. In this work, the potential impact of collagen-coated short polycaprolactone-fibers on cells after being printed in a hydrogel is systematically studied. The matrix is composed of eADF4(C16), a recombinant spider silk protein that is cytocompatible but non-adhesive for cells. Consequently, the impact of fibers could be exclusively examined, excluding secondary effects induced by the matrix. Applying this model system, a significant impact of such fillers on rheology and cell behavior is observed. Strikingly, it could be shown that fibers reduce cell viability upon printing but subsequently promote cell performance in the printed construct, emphasizing the need to distinguish between in-print and post-print impact of fillers in bio-inks.
开发能够3D打印成具有足够形状保真度的含细胞生物制品的生物墨水要求极高。通过在水凝胶中应用高聚合物浓度可以实现结构完整性和良好的机械性能。不幸的是，这往往是以细胞性能为代价的，因为细胞可能被困在致密的基质中。这个缺点可以通过加入纤维作为增强填料来解决，这些纤维可以加强整体生物墨水结构，并提供细胞可以附着和排列的二级微观结构，从而提高细胞活性。在这项工作中，系统地研究了胶原涂层的短聚己内酯纤维在水凝胶中打印后对细胞的潜在影响。基质由eADF4(C16)组成，这是一种重组蜘蛛丝蛋白，具有细胞相容性，但对细胞无粘附性。因此，可以专门研究纤维的影响，排除基质引起的二次效应。应用这个模型系统，可以观察到这种填料对流变学和细胞行为有显著影响。引人注目的是，可以证明纤维在打印时会降低细胞活力，但随后会促进打印构建物中的细胞性能，这强调了区分生物墨水中填料在打印时和打印后的影响的必要性。
