The Importance of Protecting the Structure and Viability of Adipose Tissue for Fat Grafting.

Fat grafting is widely used for soft-tissue augmentation; however, the related clinical outcome remains variable and technique-dependent. The mechanisms underlying fat graft survival are not fully understood, particularly regarding the contributions of different cell types, such as functional adipocytes. This study evaluated the importance of adipose tissue structure and viability in fat grafting and, to some extent, revealed the effect of adipocytes in fat grafting.Human lipoaspirate was harvested using suction-assisted liposuction and processed using three separate methods: cotton-pad filtration, soft centrifugation (400 g for 1 minute), and Coleman centrifugation (1200 g for 3 minutes). The three sample types were then subjected to cotton-pad concentration to exclude the influence of the purification efficiency. Adipose tissue structure and viability, the numbers of adipose-derived stem cells, and their proliferation and multilineage differentiation abilities were compared in vitro. The volume retention rate and fat graft quality were evaluated in vivo.Cell structure destruction and viability decline were more evident in the Coleman centrifugation group (31.1 ± 5.7 altered cells, 0.748 ± 0.335 mmol/liter of transported glucose) compared to the cotton-pad filtration group (7.2 ± 1.9 altered cells, 1.605 ± 0.385 mmol/liter of transported glucose) and the soft centrifugation group (12.0 ± 3.1 altered cells, 1.393 ± 0.517 mmol/liter of transported glucose). However, no intergroup differences were observed in the numbers, proliferation, or multilineage differentiation abilities of adipose-derived stem cells. After transplantation, the volume retention rates were similar in the three groups. However, greater structural and functional damage was associated with poorer graft quality, including decreased levels of graft viability, vessel density, and vascular endothelial growth factor secretion and increased levels of vacuoles, necrotic areas, fibrosis, and inflammation.Protecting adipose tissue structure and viability is crucial for improving fat grafting outcomes. In this study, cotton-pad filtration induced less damage of adipose tissue structure and viability than did centrifugation, suggesting that it is more suitable for fat purification.PLEASE SUPPLY STATEMENT.