Sphere-shaped nano-hydroxyapatite/chitosan/gelatin 3D porous scaffolds increase proliferation and osteogenic differentiation of human induced pluripotent stem cells from gingival fibroblasts

Abstract

Hydroxyapatite (HA) is an important component of human bone and bone tissue engineering scaffolds. A plethora of bone tissue engineering scaffolds have been synthesized so far, including nano-HA/chitosan/gelatin (nHA/CG) scaffolds; and for seeding cells, stem cells, especially induced pluripotent stem cells (iPSCs), have been a promising cell source for bone tissue engineering recently. However, the influence of different HA nano-particle morphologies on the osteogenic differentiation of human iPSCs (hiPSCs) from human gingival fibroblasts (hGFs) is unknown. The purpose of this study was to investigate the osteogenic differentiation of hiPSCs from hGFs seeded on nHA/CG scaffolds with 2 shapes (rod and sphere) of nHA particles. Firstly, hGFs isolated from discarded normal gingival tissues were reprogrammed into hiPSCs. Secondly, hiPSCs were seeded on rod-like nHA/CG (rod-nHA/CG) and sphere-shaped nHA/CG (sphere-nHA/CG) scaffolds respectively and then cell/scaffold complexes were cultured in vitro. Scanning electron microscope, hematoxyline and eosin (HE) staining, Masson's staining, and quantitative real-time polymerase chain reaction techniques were used to examine hiPSC morphology, proliferation, and differentiation on rod-nHA/CG and sphere-nHA/CG scaffolds. Finally, hiPSCs composited with 2 kinds of nHA/CG were transplanted in vivo in a subcutaneous implantation model for 12 weeks; pure scaffolds were also transplanted as a blank control. HE, Masson's, and immunohistochemistry staining were applied to detect new bone regeneration ability. The results showed that sphere-nHA/CG significantly increased hiPSCs from hGF proliferation and osteogenic differentiation in vitro. hiPSCs and sphere-nHA/CG composities generated large bone, whereas hiPSCs and rod-nHA/CG composities produced tiny bone in vivo. Moreover, pure scaffolds without cells almost produced no bone. In conclusion, our work provided a potential innovative bone tissue engineering approach using clinically discarded gingival tissues and sphere-nHA/CG scaffolds.

In vitro interaction of human Wharton's jelly mesenchymal stem cells with biomimetic 3D scaffold

“…Its presence in scaffold, not only produces chemical stimuli which remarkably enhance the physical attachments of cells, but also creates surface roughness for further stimulation cell‐surface adhesion . It is interesting to note that the shape of the nHA, whether spherical or slender, has significant impact on proliferation and osteogenic differentiation of stem cells …”

“…6,8 It is interesting to note that the shape of the nHA, whether spherical or slender, has significant impact on proliferation and osteogenic differentiation of stem cells. 47 Besides chemical properties, as already mentioned, topography and pore structure are physical characteristics of the scaffold that can affect seeded cell activity. The technique that we employed in manufacturing the scaffold was freeze drying combined with particle leaching.…”

Regulation and Directing Stem Cell Fate by Tissue Engineering Functional Microenvironments: Scaffold Physical and Chemical Cues

“…Some studies have found that topography can also affect the differentiation lineages of cells. Several lineages including chondrogenic differentiation, osteogenic differentiation, and neuronal differentiation have been studied [101][102][103].…”

Induced Pluripotent Stem Cells in Dental and Nondental Tissue Regeneration: A Review of an Unexploited Potential

“…Notably, the sphere-shaped nano-HA in HA/CG scaffolds greatly improved the osteogenic differentiation of human iPSCs as compared to rod-shaped. Consequently, human iPSCs and sphere-shaped nano-HA/CG composites generated a significant amount of bone in vivo [121].…”