Preparation of alginate hydrogel with human-derived adipose tissue to improve fat graft survival and adipogenesis

Autologous fat and synthetic and natural polymers have been used as materials and scaffolds in adipose tissue (AD) regeneration, combining various polymers and biological components, including extracellular matrix molecules, decellularized matrix, and adipose-derived stem cells, which have been studied to improve the adipogenesis ability of scaffolds. This study used human AD as the scaffold material, with a great source of biomaterials closest to the human body. We report a simple and facile scaffold fabrication method using a natural polymer, alginate, and human AD and confirmed the adipogenesis ability in vivo. Scaffold fabrication was performed by simply mixing human AD with alginate and cross-linking in a non-cytotoxic way, using CaCl₂ solution. This method allows facile control of the shape and mechanical properties of the scaffold, which has great advantages in medical and aesthetic applications. In vitro experiments demonstrated the viability and secretion of adipokines in the scaffold. Four weeks of in vivo experiments showed that alginate protected human AD, which aided in AD survival, and that volume and shape were better preserved. Furthermore, we confirmed that our scaffold enhanced the adipose regeneration of the host animal and increased adipogenesis of the transplanted human AD by gene expression analysis.