Peng Zhangsong, Dong Ziqing, Chang Qiang, Zhan Weiqing, Zeng Zhaowei, Zhang Shengchang, Lu Feng
Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University , Guang Zhou, P.R. China .
Tissue Eng Part C Methods. 2014 Nov;20(11):875-85. doi: 10.1089/ten.TEC.2013.0431. Epub 2014 Mar 31.
Tissue engineering chamber (TEC) makes it possible to generate significant amounts of mature, vascularized, stable, and transferable adipose tissue. However, little is known about the role of the chamber in tissue engineering. Therefore, to investigate the role of inflammatory response and the change in mechanotransduction started by TEC after implantation, we placed a unique TEC model on the surface of the groin fat pads in rats to study the expression of cytokines and tissue development in the TEC. The number of infiltrating cells was counted, and vascular endothelial growth factor (VEGF) and monocyte chemotactic protein-1 (MCP-1) expression levels in the chamber at multiple time points postimplantation were analyzed by enzyme-linked immunosorbent assay. Tissue samples were collected at various time points and labeled for specific cell populations. The result showed that new adipose tissue formed in the chamber at day 60. Also, the expression of MCP-1 and VEGF in the chamber decreased slightly from an early stage as well as the number of the infiltrating cells. A large number of CD34+/perilipin- perivascular cells could be detected at day 30. Also, the CD34+/perilipin+ adipose precursor cell numbers increased sharply by day 45 and then decreased by day 60. CD34-/perilipin+ mature adipocytes were hard to detect in the chamber content at day 30, but their number increased and then peaked at day 60. Ki67-positive cells could be found near blood vessels and their number decreased sharply over time. Masson's trichrome showed that collagen was the dominant component of the chamber content at early stage and was replaced by newly formed small adipocytes over time. Our findings suggested that the TEC implantation could promote the proliferation of adipose precursor cells derived from local adipose tissue, increase angiogenesis, and finally lead to spontaneous adipogenesis by inducing aseptic inflammation and changing local mechanotransduction.
组织工程腔室（TEC）使得生成大量成熟、血管化、稳定且可移植的脂肪组织成为可能。然而，关于该腔室在组织工程中的作用却知之甚少。因此，为了研究植入后TEC引发的炎症反应和机械转导变化的作用，我们将一种独特的TEC模型置于大鼠腹股沟脂肪垫表面，以研究TEC中细胞因子的表达和组织发育情况。对浸润细胞进行计数，并通过酶联免疫吸附测定法分析植入后多个时间点腔室内血管内皮生长因子（VEGF）和单核细胞趋化蛋白-1（MCP-1）的表达水平。在不同时间点采集组织样本并对特定细胞群进行标记。结果显示，在第60天时腔室内形成了新的脂肪组织。此外，腔室内MCP-1和VEGF的表达从早期开始略有下降，浸润细胞数量也减少。在第30天时可检测到大量CD34 + / perilipin - 血管周围细胞。而且，CD34 + / perilipin + 脂肪前体细胞数量在第45天时急剧增加，然后在第60天时减少。在第30天时，腔室内容物中难以检测到CD34 - / perilipin + 成熟脂肪细胞，但它们的数量增加，然后在第60天时达到峰值。Ki67阳性细胞可在血管附近发现，其数量随时间急剧减少。Masson三色染色显示，胶原蛋白在早期是腔室内容物的主要成分，随着时间的推移被新形成的小脂肪细胞所取代。我们的研究结果表明，TEC植入可促进源自局部脂肪组织的脂肪前体细胞增殖，增加血管生成，并最终通过诱导无菌性炎症和改变局部机械转导导致自发脂肪生成。
