GelMA hydrogels as tissue engineering scaffolds

Abstract

Gelatin methacryloyl (GelMA) hydrogels could be obtained by a concise crosslinking process induced by light with specific wavelengths, and possess superior biocompatibility due to various functional motifs with cell-adhesive and MMP-degradable characteristics, and controllable mechanical and biological properties by adjusting the concentration of crosslinked unsaturated bonds. Electrohydrodynamic atomization, including electrospraying, electronetting, and electrospinning, can produce scaffolds with various three-dimensional (3D) structures, physical properties, and chemical properties. In the present study, using electrospinning technique, a novel hairy HA (methacrylate modified hydroxyapatite, HAMA) reinforced GelMA electrospun fibrous membranes (EFMs) will be proposed as an artificial periosteum and be realized via a co-crosslinked double network, combining both inorganic and organic components as periosteum for bone regeneration. We found that the novel artificial periosteum promotes both osteogenesis and angiogenesis, and the effect is significantly stronger than the separated organic or inorganic part. This shows the novel artificial periosteum with an organic-inorganic co-crosslinked network is not a simple combination of the advantages of the single factors but a generation of synergy effect. We have also used the electrospraying technique, assisted by microfluidic devices, to create porous microcarriers on a large scale encapsulating NK cells for tumor immunotherapy. We found that the NK-92MI cells encapsulated microcarriers can destroy tumor cells at an early stage by secreting these factors, and with the proliferation and migration, the cells could directly affect tumor tissue at the long-term stage. The microcarriers could also work as a shield to protect incorporated NK cells from the immune response while the release of the tumor-killing factors is not affected. The attempts of artificial periosteum and NK cells incorporated microcarriers investigate the biological application of GelMA hydrogel assisted by electrohydrodynamic atomization technique.