Blum Carina, Schlegelmilch Katrin, Schilling Tatjana, Shridhar Arthi, Rudert Maximilian, Jakob Franz, Dalton Paul D, Blunk Torsten, Flynn Lauren E, Groll Jürgen
Department of Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute (BPI), University Hospital of Würzburg, Pleicherwall 2, 97070 Würzburg, Germany.
Department of Chemical and Biochemical Engineering, Thompson Engineering Building, The University of Western Ontario, London, Ontario N6A 5B9, Canada.
ACS Biomater Sci Eng. 2019 Dec 9;5(12):6655-6666. doi: 10.1021/acsbiomaterials.9b00894. Epub 2019 Nov 7.
Melt electrowriting (MEW) is an additive manufacturing technology that produces readily handleable fibrous scaffolds with controlled geometry to support cell infiltration. Although MEW scaffolds have excellent potential for cell delivery in regenerative medicine applications, studies to date have primarily focused on polymers such as poly(ε-caprolactone) (PCL) that lack bioactive cues to affect cell function. To address this aspect, MEW scaffolds with extracellular matrix (ECM) coatings were developed as a proadipogenic platform for human mesenchymal stromal cells (hMSCs). More specifically, highly flexible PCL scaffolds fabricated through MEW were coated with a complex ECM suspension prepared from human decellularized adipose tissue (DAT), purified fibronectin, or laminin to determine the effects of two key bioactive proteins present within adipose-derived ECM. In vitro studies exploring the response of human bone marrow-derived mesenchymal stromal cells cultured under adipogenic differentiation conditions indicated a high level of differentiation on all substrates studied, including unmodified PCL scaffolds and two-dimensional controls. To more fully assess the intrinsic proadipogenic capacity of the composite biomaterials, a modified culture regime was established that involved a short-term adipogenic induction in differentiation medium, followed by continued culture in maintenance medium supplemented with insulin for up to 3 weeks. Under these conditions, adipogenic differentiation was enhanced on all fiber scaffolds as compared to the tissue culture controls. Notably, the highest adipogenic response was consistently observed on the PCL + DAT scaffolds, based on the analysis of multiple markers including adipogenic gene [lipoprotein lipase, fatty acid binding protein 4 (FABP4), adiponectin, perilipin 1] and protein (FABP4, leptin) expression and intracellular triglyceride accumulation. Taken together, the PCL scaffolds incorporating DAT provide an adipoinductive microenvironment for the hMSCs, with particular applicability of this cell-instructive delivery platform for applications in plastic and reconstructive surgery.
熔体静电纺丝书写（MEW）是一种增材制造技术，可生产具有可控几何形状的易于处理的纤维支架，以支持细胞浸润。尽管MEW支架在再生医学应用中的细胞递送方面具有巨大潜力，但迄今为止的研究主要集中在缺乏影响细胞功能的生物活性线索的聚合物上，如聚（ε-己内酯）（PCL）。为了解决这一问题，开发了具有细胞外基质（ECM）涂层的MEW支架，作为人间充质基质细胞（hMSCs）的促脂肪生成平台。更具体地说，通过MEW制造的高度灵活的PCL支架用由人脱细胞脂肪组织（DAT）、纯化的纤连蛋白或层粘连蛋白制备的复合ECM悬浮液进行涂层，以确定脂肪来源的ECM中存在的两种关键生物活性蛋白的作用。在成脂分化条件下培养的人骨髓间充质基质细胞反应的体外研究表明，在所研究的所有基质上，包括未修饰的PCL支架和二维对照，都有高水平的分化。为了更全面地评估复合生物材料的内在促脂肪生成能力，建立了一种改良的培养方案，即在分化培养基中进行短期成脂诱导，然后在补充胰岛素的维持培养基中继续培养长达3周。在这些条件下，与组织培养对照相比，所有纤维支架上的成脂分化都得到了增强。值得注意的是，基于对包括成脂基因[脂蛋白脂肪酶、脂肪酸结合蛋白4（FABP4）、脂联素、围脂滴蛋白1]和蛋白质（FABP4、瘦素）表达以及细胞内甘油三酯积累在内的多个标志物的分析，在PCL+DAT支架上始终观察到最高的成脂反应。综上所述，掺入DAT的PCL支架为hMSCs提供了一个脂肪诱导微环境，这种细胞指导递送平台在整形和重建手术应用中具有特别的适用性。
