Superior Retention of Aged Fat Graft by Supplementing Young Adipose-Derived Stromal Cells in a Murine Model.

Abstract

In 2021, a meta-analysis showed that fat graft retention varied from 26% to 83%. In a retrospective study including patients with Parry-Romberg syndrome, the younger age group had higher satisfaction scores (3.8 versus 3.0) after fat grafting. Cell-assisted lipotransfer could be an alternative to overcome the instability of volume loss; however, no study has investigated its effect on older recipients. In an in vitro study, adipose-derived stromal cells (ASCs) from aged and young (52 and 8 weeks old) DsRed B6 mice were characterized by proliferation rates as percentages of Ki-67-positive cells. In addition, 68-week-old wild-type B6 mice received 150 µL of green fluorescent protein fat (from 69-week-old B6 mice) mixed with saline or 3 × 10 5 aged or young DsRed ASCs (N, A, and Y groups, respectively) on the scalp ( n = 6/group). After 8 weeks, graft volumes were evaluated using microcomputed tomography. Vessel densities were tracked by percentages of CD31 using immunofluorescence staining. Young ASCs showed higher proliferation than aged ASCs (47.1% and 26.2%, respectively; P < 0.05). The Y group showed the highest graft retention (median: N, 41.0%; A, 52.2%; Y, 65.2%; P < 0.05) and percentage of blood vessels (median: N, 27.7%; A, 43.5%; Y, 54.7%; P < 0.05) among the 3 groups. Cell-assisted lipotransfer is effective with older recipients. Higher effect was observed by supplementation with younger ASCs because of higher angiogenesis stimulation. Further validation of safety, toxicity, and allogenic grafting is required.