Introduction of ligated vessels promote the retention and regeneration of free fat: constructing a fat flap in tissue engineering chamber

Zhiyong Huang,Beichen Cai,Biao Wang,Chen Lei,Xiaobin Chen

doi:10.1080/21623945.2020.1735025

Zhiyong Huang, Beichen Cai + Show 3 more

Open Access

https://doi.org/10.1080/21623945.2020.1735025

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Abstract

ABSTRACT Background: Breast reconstruction with fat grafting has an unstable retention rate due to insufficient revascularization. Tissue Engineering Chamber (TEC) model can promote tissue regeneration in the chamber by introducing ligated vessels around the tissue. We introduced ligated vessels with free fat graft to investigate the retention rate and revascularization of grafted fat that in TEC model. Methods: SD rats (n=24) was divided into 3 groups randomly. Group A: Standard TEC model was constructed; Group B: the epigastric vessel bundles were dissected from the fat flap and ligated, fat flap was cut into granules and planted into the chamber; Group C: Free fat was planted in the chamber. At week 6, samples in the chamber were harvested. Results: Significant volume increase was observed in group A and B, while the volume decreased in group C (P<0.05). Regeneration morphology could be found according to the histological observation in A and B. Micro CT results showed the ligated vessels into grafted fat sprouting robustly, coordinated with volume changes. Conclusion: Fat grafts in TEC model could not only survive but also regenerate. The combination of fat graft and TEC could fabricate a vascularized fat flap, which was a promising method in breast reconstruction. Abbreviations: VOI: Volumes of Interest; TEC: Tissue Engineering Chamber; CAL: Cell Assisted Lipotransfer.

Highlights

In plastic surgery, there are tremendous clinical demands on correcting soft tissue defects or hypogenesis
A number of studies have shown their results of enlarging the volume of fat flaps in rats [15], rabbits [16] and pigs [17] in Tissue Engineering Chamber (TEC). This technique was famous for its construction of 56.5 ml adipose tissue from its initial volume of 5 ml in a porcine model [17]. This kind of spontaneous regeneration seemed to be specific in adipose tissue
All rats (n = 24) were divided into 3 groups as shown in Figure 1, the graphic abstract; Group A: Standard tissue engineering chamber model, the positive control, was constructed utilizing the epigastric vessel derived fat flap at the inguinal area as shown in Figure 1(b) left (n = 8); Group B: Instead of the fat flap, adipose tissue was cut into granules and planted into the silicone chamber with ligated epigastric vessel bundles as shown in Figure 1(b) middle (n = 8); Group C (n = 8): Free fat was planted in the chamber without extra vessels as shown in Figure 1(b), right

Summary

Introduction

There are tremendous clinical demands on correcting soft tissue defects or hypogenesis. The varying retention rate [8,9] after transplantation remains to be solved and when applied to large defects like breast reconstruction, a high number of grafting procedures are required [10]. Breast reconstruction with fat grafting has an unstable retention rate due to insufficient revascularization. Tissue Engineering Chamber (TEC) model can promote tissue regeneration in the chamber by introducing ligated vessels around the tissue. We introduced ligated vessels with free fat graft to investigate the retention rate and revascularization of grafted fat that in TEC model. Micro CT results showed the ligated vessels into grafted fat sprouting robustly, coordinated with volume changes. The combination of fat graft and TEC could fabricate a vascularized fat flap, which was a promising method in breast reconstruction

Methods

Results

Conclusion