Abstract
BACKGROUND: Cell-assisted lipotransfer (CAL) is a fat grafting technique that enhances graft survival by supplementing grafts with autologous stromal vascular fraction (SVF) or adipose-derived stromal cells (ASCs). However, its clinical translation has been hindered owing to inherent biological variability, potential cell viability issues, tumorigenic risk, and the complex regulatory landscape associated with cell-based therapies. To overcome these challenges, exosome has gained increasing attention as a promising non-cellular therapeutic modality capable of preserving key regenerative functions while minimizing relative concerns. This study aimed to compare the efficacy of SVF-enriched lipotransfer with fat co-transplanted with exosomes from ASCs to identify a reliable and clinically applicable non-cellular strategy for optimizing fat graft outcomes. METHODS: In vivo, minced human fat tissue mixed with phosphate-buffered saline, SVF cells, or exosomes was grafted into nude mice. Grafts were evaluated through microcomputed tomography at weeks 4 and 8 post-grafting and histological analysis at weeks 1 and 8 post-grafting. RESULTS: The exosome group showed a significantly higher volume retention rate than the control group at weeks 4 and 8 post-grafting. Histological analysis revealed that exosomes exhibited more pronounced effects in reducing inflammation, preserving perilipin-positive adipocytes, and promoting angiogenesis in the grafted fats compared with those of SVF cells. CONCLUSIONS: Our findings highlight the potential of exosomes in improving fat graft retention and overall tissue regeneration, suggesting that fat co-transplanted with exosomes from ASCs could serve as a superior alternative to SVF-enriched lipotransfer. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.