Evaluation of a novel approach for in situ soft tissue engineering by external expansion

软组织缺损的充分修复是重建外科尚未解决的问题。脂肪组织工程提供了一个潜在的解决方案，但在体外策略仍然受到严重的限制。通过真空应用的外部软组织扩张是原位脂肪组织工程的一种新的和有前途的方法，但对导致组织扩增的潜在机制知之甚少。在这里，我们将对原代人前脂肪细胞、内皮细胞和脂肪组织样本施加真空和机械应力，并将分析结果与潜在机制，如炎症、氧化应激和血管生成，所有这些都是脂肪形成的关键因素。特别是，将测定一组相关分泌生长因子和细胞因子的水平，包括新出现的脂肪形成因子，如巨噬细胞迁移抑制因子（MIF）。调查还将包括全球基因表达分析和调节蛋白的磷酸化状态的评估，以确定负责的信号通路。将在使用无毛大鼠的体内模型中验证获得的体外结果，该模型模拟外部组织扩张方法。拟议的项目将大大有助于在原位组织工程领域的进展，也将有助于了解肥胖相关的病理如何与炎症和氧化应激等过程相关联。

An adequate reconstruction of soft tissue defects is still an unsolved problem in reconstructive surgery. Adipose tissue engineering offers a potential solution but in vitro strategies are still afflicted with severe limitations. External soft tissue expansion by vacuum application is a new and promising approach for in situ adipose tissue engineering but little is known about the underlying mechanisms that lead to tissue augmentation. Here, we will apply vacuum as well as mechanical stress to primary human preadipocytes, endothelial cells and adipose tissue samples and will analyse the outcome with regard to potential mechanisms like inflammation, oxidative stress, and angiogenesis, all being crucial factors in adipogenesis. In particular, the levels of a panel of relevant secreted growth factors and cytokines including emerging adipogenic factors such as macrophage migration inhibitory factor (MIF) will be determined. The investigations will also encompass a global gene expression analysis and the evaluation of the phosphorylation state of regulatory proteins to identify responsible signaling pathways. The obtained in vitro results will be verified in an in vivo model using hairless rats, which mimics the external tissue expansion approach. The proposed project will significantly contribute to progress in the field of in situ tissue engineering and also will help to understand how obesity-related pathologies are associated with processes such as inflammation and oxidative stress.