Quality- and Quantity-cultured Peripheral Blood Mononuclear Cell Improve the Fat Graft Vascularization and Survival

Abstract

INTRODUCTION: Fat grafting is a valuable technique in soft-tissue reconstruction. However, ischemia of the grafted tissue with subsequent necrosis and tissue loss impede us from having satisfying long-term results. Recently, the quality and quantity (QQ) culture has been established to increase the vasculogenic potential of endothelial progenitor cells in peripheral blood-derived mononuclear cells (MNCs). Our experiment was designed to test whether QQ-cultured MNC (MNC-QQ) can contribute to vasculogenesis in the human fat graft and decrease the tissue loss. METHODS: Adipose tissue and peripheral blood were harvested from healthy subjects. Fat grafts were created with peripheral blood-derived MNC (N = 16), MNC-QQ (N = 16), and stromal vascular fraction (N = 16) before grafting in BALB/c nude mice, and compared to nonenriched control fat grafts (N = 16). Grafts were explanted after 1 and 7 weeks and analyzed by weight persistence, immunohistochemistry, and quantitative polymerase chain reaction. RESULTS: Weight persistence after 7 weeks was significantly higher in the MNC-QQ group (89.8% ± 3.5%) and SVF group (90.1 ± 4.2) compared to control (70.4% ± 6.3%). With 96.6 ± 6.5 vessels/mm2, grafts in the MNC-QQ group had the most dense vessel network and scored significantly better than control (70.4 ± 5.6 vessels/mm2). MNC-QQ exerted a direct effect on vasculogenesis by integrating in vessels, and a paracrine VEGF-mediated effect. Tissue consisting of fibrosis and perilipin-positive adipocytes was unchanged among all groups. CONCLUSIONS: QQ-cultured MNC containing endothelial progenitor cell stimulates the formation of a blood vessel network in the fat graft and enhances the graft survival, indicating its potential for clinical fat grafting.