3D Bioprinting for Tissue Engineering Amidst the Century Cataclysm

Abstract

Objective: Nanofat grafting has been reported to improve tissue repair by the Stromal Vascular Fraction (SVF) of nanofat. However, the oil and liquid portions of fat tissues were released by mechanical emulsification during the nanofat procedure. Here, we reported a simple method to remove the oil and water for concentrating nanofat. Methods: The concentrate of nanofat was obtained by processing nanofat using negative pressure produced by syringer and two-step centrifugation. The volume of oil and fat tissue as well as morphological changes of nanofat concetrate obtained by different procedures was examined. Meanwhile, the SVF numbers, the proliferation and differentiation capacity of Adipose-Derived Stem Cells (ADSCs) were determined. The clinical outcome of nanofat concentrate in treatment hypertrophic scar was evaluated. Results: The centrifugation and negative pressure had no significant effect on the proliferation activity of the SVF in the concentrate of nanofat. The concentrated rate after 0, 15, 30 and 60 times of emulsification was 2.08±0.042, 2.63 ± 0.07, 3.8 ± 0.01 and 8.2 ± 0.12 times greater than the original, respectively. The SVF number per 10 ml of fat in the above-mentioned groups were increased by 1.80 ± 0.15, 2.68 ± 0.27, 4.64 ± 0.20 and 3.44 ± 0.27 times, respectively. The capacity of cell proliferation and differentiation decreased significantly after more than 30 times emulsification. The concentrates of nanofat effectively improve the appearence and hardness of hypertrophic scar. Conclusion: The nanofat concentrate prepared by our method include more SVF cells and less oil and might be more effective during clinical use.