Polymer therapy: a novel treatment to improve fat graft viability

Autologous fat grafting is currently undergoing a renaissance. However, fat grafts are limited by unpredictable survival. Poloxamers can act as tissue surfactants. These nonionic surfactants have been shown to stabilize the membranes of damaged cells and to protect against injury and apoptosis in numerous models. This study was designed to investigate the ability of poloxamers to protect harvested adipocytes and to increase fat graft survival.

Lipoaspirate was obtained from surgical patients. Samples were washed in normal saline, centrifuged at 200 g, treated with various poloxamers or poloxamer components for 30 minutes, centrifuged at 200 g, and implanted into the flanks of nude mice in 1.0-cc, 1.0-g lobules. The grafts were explanted serially for 10 days and at 6 weeks. Endpoints were weight, apoptosis, cell viability, DNA content, and histology.

Grafts treated with poloxamers P188, F108, and F127 demonstrated increased graft survival by weight. Fat grafts treated with poloxamers L64 and P188 demonstrated improvement in cell viability, and those treated with poloxamers L64, P188, and F38 demonstrated improved histology. P188-treated grafts demonstrated a 50 percent reduction in apoptosis compared with saline-treated controls (p < 0.05) and an overall 72 percent survival by weight at 6 weeks. P188 demonstrated statistically significant improvement by weight, DNA content, histology, and cell viability (89 percent versus 33 percent).

The authors demonstrate that poloxamers, with membrane-sealing capability, can increase graft survival. Among these poloxamers, P188 demonstrated statistically significant improvement in apoptosis, graft survival by weight, cell viability, DNA content, and histology.