Topographical biointerface regulating cellular functions for bone tissue engineering

Abstract

The physiochemical properties of the implant interface significantly influence cell growth, differentiation, cellular matrix deposition, and mineralisation, and eventually, determine the bone regeneration efficiency. Cells directly sense and respond to the physical, chemical, and mechanical cues of the implant surface, and it is increasingly recognized that surface topography can evoke specific cellular responses, conferring biological functions on substrate materials and regulating tissue regeneration. Current progress towards the fundamental understanding of the interplay between the cell and topographical surface has been made by combined advance in fabrication technologies and cell biology. Particularly, the precise fabrication and control of nano/microscale topographies can provide the fundamental knowledge of the mechanotransduction process that governs the cellular response as well as the knowledge of how the specific features drive cells towards a defined differentiation outcome. In this review, we first introduce common techniques and substrate materials for designing and fabricating micro/nano‐topographical surfaces for bone regeneration. We then illustrate the intrinsic relationship of topological cues, cellular signal transduction, and cell functions and fates in osteogenic differentiation. Finally, we discuss the challenges and the future of using topological cues as a cell therapy to direct bone tissue regeneration.

Bioinspired scaffolds based on aligned polyurethane nanofibers mimic tendon and ligament fascicles

“…It is commonly accepted that manipulating the topographical factors of matrices could regulate cell behavior including cell morphology and orientation. [ 37 ] To determine the influence of alignment topography and 3D configuration of nanofibers on cell morphology, both seeded‐scaffolds were stained after 7 days of culture. The cytoskeleton was stained red with FITC‐conjugated phalloidin, and the nucleus was stained blue with DAPI.…”

“…Cells recognize and respond to contact guidance cues, which extend to nanoscale topographical features. [ 37,57 ] Such alignment topography of nanofibers is deemed to be an ideal substrate for facilitating the regeneration of tissues with similar structures, like tendons, ligaments, nerve, cardiac, and skeletal muscles, since they can convey topographical cues to cells and consequently promote higher expression of the corresponding markers, as reported by several researchers. [ 2,73 ] Thus, the promotion of MSCs toward tendon lineage on EPU mats and EPU bundles compared to TCP could be attributed to the alignment topography of nanofibers.…”

“…It is commonly accepted that manipulating the topographical factors of matrices could regulate cell behavior including cell morphology and orientation. [37] To determine the influence of alignment topog- As shown in fluorescent images (Figure 4B), MSCs were well attached to all samples but there was a meaningful difference in cell morphology depending on which substrate structure the cells were in contact with. Moreover, cells exhibited a stellate-patterned morphology and spread in random orientation on TCP (control), whereas for 2D and 3D aligned EPU nanofibers (i.e., mats and bundles scaffolds, respectively), cells displayed a spindle-patterned morphology with elongation and were oriented along the underlying fiber direction.…”

Enhancing osseointegration of titanium implants through MC3T3‐E1 protein‐gelatin polyelectrolyte multilayers

“…To address the common issue of metal implant loosening and negative reactions to material implantation, it is necessary to develop an innovative biomaterial. The titanium‐based implant should be accompanied by a microenvironment that supports osteogenic differentiation and anti‐inflammatory responses, thereby facilitating bone regeneration and osseointegration 21,22 . Studies have shown that bioactive substances such as RGD, OGP, and ECM play a crucial role in bone regeneration by stimulating osteoblast proliferation, differentiation, alkaline phosphatase activity, collagen secretion, and matrix mineralization 23–25 …”

“…Figure 7A, C inflammatory responses, thereby facilitating bone regeneration and osseointegration. 21,22 Studies have shown that bioactive substances such as RGD, OGP, and ECM play a crucial role in bone regeneration by stimulating osteoblast proliferation, differentiation, alkaline phosphatase activity, collagen secretion, and matrix mineralization. [23][24][25] In this study, a layer-by-layer self-assembly technique was employed to modify the surface of titanium-based materials with MC3T3-E1 protein.…”