# Injectable Scaffolds for Adipose Tissue Reconstruction

## TL;DR

Injectable scaffolds are being developed as alternatives to fat grafting for soft tissue reconstruction, aiming to overcome limitations like unpredictable resorption and donor site issues.

## Contribution

The paper reviews injectable scaffolds for adipose tissue engineering, comparing natural, synthetic, and extracellular matrix-derived options and their translational potential.

## Key findings

- Natural scaffolds offer good biocompatibility but lack mechanical strength and degrade quickly.
- Synthetic scaffolds can be tailored but need biofunctionalization for tissue integration.
- Adipose-derived extracellular matrix scaffolds mimic native tissue and support adipogenesis and angiogenesis.

## Abstract

Autologous fat grafting is the main surgical technique for soft tissue reconstruction. However, its clinical use with more extended volumes is limited by repeated procedures due to the little possibility of banking tissue, donor-site morbidity and unpredictable graft resorption rates. To overcome these problems, adipose tissue engineering has focused on developing injectable scaffolds. Most of them are hydrogels that closely mimic the biological, structural and mechanical characteristics of native adipose tissue. This review provides an overview of current injectable scaffolds designed to restore soft tissue volume defects, emphasizing their translational potential and future directions. Natural injectable scaffolds exhibit excellent biocompatibility but degrade rapidly and lack mechanical strength. Synthetic injectable scaffolds provide tunable elasticity and degradation rates but require biofunctionalization to support cell adhesion and tissue integration. Adipose extracellular matrix-derived injectable scaffolds are fabricated by decellularization of adipose tissue. Accordingly, they combine bio-mimetic structure with intrinsic biological cues that stimulate host-driven adipogenesis and angiogenesis, thus representing a translatable “off-the-shelf” alternative to autologous fat grafting. However, despite this broad spectrum of available injectable scaffolds, the establishment of clinically reliable soft tissue substitutes capable of supporting large-volume and long-lasting soft tissue reconstruction still remains an open challenge.