An adipose extracellular matrix-derived biomaterial for soft tissue reconstruction

Abstract

Soft tissue defects can result from traumatic injury, congenital defects, and medical procedures such as tumor resection. Patients who require soft tissue reconstruction have limited options and often must use autologous tissue for reconstruction, which has the adverse effects of donor site morbidity. This study explores the development of an adipose extracellular matrix – based biomaterial for the repair of soft tissue defects. The adipose extracellular matrix (ECM) is obtained through mechanical and chemical treatments to remove all the cells and lipids from intact human adipose tissue. The degradation properties of the ECM-based biomaterial can be modulated with chemical crosslinking, allowing for control over the degradation rate of the biomaterial. Material characterization of the adipose ECM was carried out through proteomics, mechanical testing, and thermal analysis. The adipose matrix supported adipose stem cell growth and differentiation in vitro, providing tissue-specific bioactive cues to improve adipogenic differentiation. In vivo biocompatibility studies showed minimal inflammatory response to the biomaterial and stable volume retention through 12 week studies. When compared with the clinical standard of fat grafting, the acellular adipose matrix demonstrated the advantages of facilitating new adipose tissue regeneration rather than relying on transplantation of autologous fat which has the risk of necrosis, cyst formation and calcification due to the limited viability of transplanted adipocytes. The adipose ECM can also be used with adipose stem cell delivery, providing a protective environment for stem cell engraftment, which in turn facilitates new adipose tissue formation. The adipose matrix provides a versatile biomaterial for soft tissue regeneration hat can be used for allogenic applications, circumventing the need for autologous tissue for reconstruction