Phospholipid‐induced silk fibroin hydrogels and their potential as cell carriers for tissue regeneration

Abstract

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. ; This paper was supported by the REMIX Project, funded by the European Union's Horizon 2020 Research and Innovation programme under the Maria Sklodowska‐Curie Grant agreement n. 778078. Financial support is acknowledged from Chulalongkorn Academic Advancement into Its 2nd Century (CUAASC), SPARTAN project (PTDC/CTM‐BIO/4388/2014), and NORTE 2020 Structured Project within the R&D&I Structured Project, cofunded by Norte2020—Programa Operacional Regional do Norte. Chavee Laomeephol was awarded with The 100th Anniversary Chulalongkorn University Fund for his Doctoral Scholarship and The 90th Anniversary Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund). Marta Guedes acknowledges the Portuguese Foundation for ...