In Vitro Evaluation of Mechanical Fat Processing Devices: Impact on Adipocytes and Adipose-Derived Stem Cells

In the fat grafting procedure, the new European Regulations and the necessity to perform minimal manipulation processing require the verification of security and performance levels of each device and, in this particular context, functional and tissue responses. The aim of this study is to evaluate the integrity of adipocytes and adipose-derived stromal/stem cells (ADSCs) after their processing using two new mechanical devices operating with a closed system. In this study, two new fat processing systems were assessed. We also considered the biological results of the processing and compared them with the results obtained from Coleman's procedure, the golden standard procedure in fat processing. Histological evaluations revealed the preservation of the fat morphology after both processing types, with similar cellular yields of the extracted ADSCs. The adopted techniques enable the isolation of ADSCs with robust differentiation potential toward adipogenic, chondrogenic, and osteogenic lineages. Furthermore, adipose tissue samples exhibit high efficiency in extracellular vesicle secretion, indicating a promising potential for therapeutic and regenerative applications. The results suggest that the new systems allow the preservation of fat morphology, stemness, and regenerative potential. The novel processing technique proposed by the authors consists of a closed-loop mechanical system that combines continuous filtration and emulsification of adipose tissue through saline washing, aimed at removing biological debris and residual pharmacological agents.