Mechanotopography‐Driven Design of Dispersible Nanofiber‐Laden Hydrogel as a 3D Cell Culture Platform for Investigating Tissue Fibrosis

Abstract

Fibrosis is one of the most frequent occurrences during one's lifetime, identified by various physiological changes including, most notably, excessive deposition of extracellular matrix (ECM). Despite its physiological importance, it is still a significant challenge to conduct a systematic investigation of tissue fibrosis, mainly due to the lack of in vitro 3D tissue model that can accurately portray the characteristic features of fibrotic events. Herein, a hybrid hydrogel system incorporating dispersible nanofibers is developed to emulate highly collagenous deposits formed within a fibrotic tissue leading to altered mechanotopographical properties. Micrometer‐length, aqueous‐stable nanofibers consisting of crosslinked gelatin network embedded with graphene oxide (GO) or reduced graphene (rGO) are infused into hydrogel, resulting in controllable mechanotopographical properties while maintaining permeability sufficiently enough for various cellular activities. Ultimately, the ability to induce fibrotic behavior of fibroblasts cultured in these mechanotopography‐controlled, nanofiber‐laden hydrogels is investigated in detail.

Modulating Myofibroblastic Differentiation of Fibroblasts through Actin-MRTF Signaling Axis by Micropatterned Surfaces for Suppressed Implant-Induced Fibrosis

“…In response to local stress signals and biomechanical tension, FBs proliferate and eventually differentiate into myofibroblasts [ 36 , 37 ]. MRTFs are serum response factor (SRF) cofactors that have been demonstrated to be key mediators that promote myofibroblastic differentiation [ 38 , 39 ].…”

Controllable graphene oxide-based biocompatible hybrid interface as an anti-fibrotic coating for metallic implants

“…In contrast, GO-COL composites form a 3D fibrous structure that creates a softer matrix between the cells and the glass, maintaining the quiescent phenotypic nature of the fibroblasts. In addition, the topological nanostructure of the surface also played an important role in inhibiting the differentiation of fibroblasts into myofibroblasts [ 46 ]. The cross-linking of GO with COL, forming anisotropic fibers, can potentially regulate the expression of α-SMA in fibroblasts, as observed in previous studies [ 47 ].…”

Multiscale Control of Nanofiber-Composite Hydrogel for Complex 3D Cell Culture by Extracellular Matrix Composition and Nanofiber Alignment

“…Actin filaments and nuclei of the cells were visualized by fluorescent labeling [ 15 ]. The samples were fixed with 4% formaldehyde for 30 min, permeabilized with 0.1% Triton X-100 for 1 h, and blocked with 2% bovine serum albumin for 2 h in phosphate buffered saline (PBS).…”

“…Nanocomposite hydrogels incorporating nanofibers as a filler have received considerable attention in recent years as a biomimetic approach to recreate the cellular microenvironment that can more accurately recreate the complexity of heterogeneous tissue architecture [ 15 – 20 ]. Nanofibers prepared by electrospinning have been widely utilized in tissue engineering, as the meshwork of interlaid nanofibers has been shown to be quite effective as scaffolds, promoting cell adhesion and growth [ 21 ].…”

“…Taking advantage of this strategy, herein, photocrosslinkable gelatin nanofibers embedded with MNPs were incorporated and magnetically aligned in a hydrogel to control various phenotypes of encapsulated cells. The aqueous-dispersible and magnetically active gelatin nanofibers were generated by electrospinning gelatin and MNPs, followed by ultrasonic cutting into micrometer length, and chemical crosslinking to prevent dissolution in aqueous media [ 15 , 16 ]. The concentration of MNP in nanofiber was controlled to maximize the nanofiber movement and alignment.…”