Jiang Wenqing, Cai Junrong, Guan Jingyan, Liao Yunjun, Lu Feng, Ma Jingjing, Gao Jianhua, Zhang Yuteng
Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China.
Department of Plastic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
Front Cell Dev Biol. 2021 Sep 20;9:723057. doi: 10.3389/fcell.2021.723057. eCollection 2021.
Autologous fat grafting has been a widely used technique; however, the role of adipose-derived stem cells (ASCs), extracellular matrix (ECM), and microenvironment in fat regeneration are not fully understood. Lipoaspirates were obtained and processed by inter-syringe shifting to remove adipocytes, yielding an adipocyte-free fat (Aff). Aff was then exposed to lethal dose of radiation to obtain decellularized fat (Df). To further remove microenvironment, Df was rinsed with phosphate-buffered saline (PBS) yielding rinsed decellularized fat (Rdf). Green fluorescent protein (GFP) lentivirus (LV-GFP)-transfected ASCs were added to Df to generate cell-recombinant decellularized fat (Crdf). Grafts were transplanted subcutaneously into nude mice and harvested over 3 months. Removal of adipocytes (Aff) didn't compromise the retention of fat grafts, while additional removal of stromal vascular fraction (SVF) cells (Df) and microenvironment (Rdf) resulted in poor retention by day 90 (Aff, 82 ± 7.1% vs. Df, 28 ± 6.3%; < 0.05; vs. Rdf, 5 ± 1.2%; < 0.05). Addition of ASCs to Df (Crdf) partially restored its regenerative potential. Aff and Crdf exhibited rapid angiogenesis and M2-polarized macrophages infiltration, in contrast to impaired angiogenesis and M1-polarized inflammatory pattern in Df. GFP + ASCs participated in angiogenesis and displayed a phenotype of endothelial cells in Crdf. Adipose ECM and microenvironment have the capacity to stimulate early adipogenesis while ECM alone cannot induce adipogenesis . By directly differentiating into endothelial cells and regulating macrophage polarization, ASCs coordinate early adipogenesis with angiogenesis and tissue remodeling, leading to better long-term retention and greater tissue integrity.
自体脂肪移植是一种广泛应用的技术；然而，脂肪来源干细胞（ASC）、细胞外基质（ECM）和微环境在脂肪再生中的作用尚未完全明确。获取脂肪抽吸物并通过注射器间转移进行处理以去除脂肪细胞，得到无脂肪细胞脂肪（Aff）。然后将Aff暴露于致死剂量的辐射下以获得脱细胞脂肪（Df）。为了进一步去除微环境，用磷酸盐缓冲盐水（PBS）冲洗Df，得到冲洗后的脱细胞脂肪（Rdf）。将绿色荧光蛋白（GFP）慢病毒（LV-GFP）转染的ASC添加到Df中以生成细胞重组脱细胞脂肪（Crdf）。将移植物皮下移植到裸鼠体内，并在3个月内进行取材。去除脂肪细胞（Aff）并不影响脂肪移植物的留存，而额外去除基质血管成分（SVF）细胞（Df）和微环境（Rdf）则导致在第90天时留存率较差（Aff，82±7.1% vs. Df，28±6.3%；P<0.05；vs. Rdf，5±1.2%；P<0.05）。将ASC添加到Df中（Crdf）可部分恢复其再生潜力。与Df中血管生成受损和M1极化炎症模式相反，Aff和Crdf表现出快速的血管生成和M2极化巨噬细胞浸润。GFP+ASC参与血管生成并在Crdf中表现出内皮细胞表型。脂肪ECM和微环境有能力刺激早期脂肪生成，而单独的ECM不能诱导脂肪生成。通过直接分化为内皮细胞并调节巨噬细胞极化，ASC协调早期脂肪生成与血管生成和组织重塑，从而实现更好的长期留存和更高的组织完整性。
