Silk fibroin (SF) hydrogels can be obtained via self-assembly, but this process takes several days or weeks, being unfeasible to produce cell carrier hydrogels. In this work, a phospholipid, namely, 1,2-dimyristoyl-sn-glycero-3-phospho-(1'-rac-glycerol) sodium salt (DMPG), was used to induce and accelerate the gelation process of SF solutions. Due to the amphipathic nature and negative charge of DMPG, electrostatic and hydrophobic interactions between the phospholipids and SF chains will occur, inducing the structural transition of SF chains to the beta sheet and consequently a rapid gel formation is observed (less than 50 min). Moreover, the gelation time can be controlled by varying the lipid concentration. To assess the potential of the hydrogels as cell carriers, several mammalian cell lines, including L929, NIH/3T3, SaOS-2, and CaSki, were encapsulated into the hydrogel. The silk-based hydrogels supported the normal growth of fibroblasts, corroborating their cytocompatibility. Interestingly, an inhibition in the growth of cancer-derived cell lines was observed. Therefore, DMPG-induced SF hydrogels can be successfully used as a 3D platform for in situ cell encapsulation, opening promising opportunities in biomedical applications, such as in cell therapies and tissue regeneration.

中文翻译：

---

磷脂诱导的丝素蛋白水凝胶及其作为组织再生的细胞载体的潜力。

丝素蛋白（SF）水凝胶可以通过自组装获得，但是此过程需要几天或几周的时间，无法生产细胞载体水凝胶。在这项工作中，磷脂，即1,2-二肉豆蔻酰基-sn-甘油-3-磷酸-（1'-rac-甘油）钠盐（DMPG），被用来诱导和加速SF溶液的胶凝过程。由于DMPG的两亲性质和负电荷，磷脂和SF链之间会发生静电和疏水相互作用，从而导致SF链向β折叠的结构转变，从而观察到快速的凝胶形成（少于50分钟）。此外，可以通过改变脂质浓度来控制胶凝时间。为了评估水凝胶作为细胞载体的潜力，包括L929，NIH / 3T3，SaOS-2和CaSki等几种哺乳动物细胞系，被封装到水凝胶中。丝绸基水凝胶支持成纤维细胞的正常生长，证实了它们的细胞相容性。有趣的是，观察到了对源自癌症的细胞系生长的抑制。因此，DMPG诱导的SF水凝胶可以成功地用作3D平台进行原位细胞封装，从而在生物医学应用（例如细胞疗法和组织再生）中打开了有希望的机会。