Martinelli Chiara, Bocconi Alberto, Milone Sofia, Baldissera Teresa, Cherubin Leonardo, Buccioli Giovanni, Perottoni Simone, Conci Claudio, Cerullo Giulio, Osellame Roberto, Chirico Giuseppe, Jacchetti Emanuela, Raimondi Manuela Teresa
Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Piazza L. da Vinci, 32, 20133 Milan, Italy.
Institute for Photonics and Nanotechnologies (IFN), CNR and Department of Physics, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy.
Lab Chip. 2025 Jan 28;25(3):423-439. doi: 10.1039/d4lc00898g.
The process of angiogenesis plays a pivotal role in skin regeneration, ensuring the provision of nutrients and oxygen to the nascent tissue, thanks to the formation of novel microvascular networks supporting functional tissue regeneration. Unfortunately, most of the current therapeutic approaches for skin regeneration lack vascularization, required to promote effective angiogenesis. Thus, tridimensional models, complemented with specific biochemical signals, can be a valuable tool to unravel the neovascularization mechanisms and develop novel clinical strategies. In this work, we designed and validated a tridimensional microstructured dynamic model of the dermal perivascular microenvironment on a chip. We carried out the fabrication of an array of microstructures by two-photon laser polymerization, then used as a 3D substrate for co-culture of human dermal fibroblasts and endothelial cells. We included the substrate in a miniaturized optically accessible bioreactor (MOAB) which provides the physiological interstitial flow, upon perfusion in the presence or absence of the pro-angiogenic stimuli VEGF and TGF-β1. We determined the parameters to be applied under dynamic conditions by an model simulating individual 3D microenvironments within the bioreactor's chambers. We computed the fluid velocity and wall shear stress acting on endothelial cells along with the oxygen concentration profile, and we chose the most suitable flow rate for maintaining dermal physiological conditions. Experimental results showed the effectiveness of the developed platform as a 3D dynamic model of angiogenesis. This is the first combined experimental and computational study involving chemically stimulated 3D co-cultures for successfully simulating the physiological dermal perivascular microenvironment.
血管生成过程在皮肤再生中起着关键作用，通过形成支持功能性组织再生的新型微血管网络，确保为新生组织提供营养和氧气。不幸的是，目前大多数皮肤再生治疗方法缺乏促进有效血管生成所需的血管化。因此，辅以特定生化信号的三维模型可能是揭示新血管形成机制和开发新临床策略的宝贵工具。在这项工作中，我们设计并验证了一种芯片上真皮血管周围微环境的三维微结构动态模型。我们通过双光子激光聚合制造了一系列微结构，然后将其用作人真皮成纤维细胞和内皮细胞共培养的三维基质。我们将该基质置于一个小型光学可及生物反应器（MOAB）中，该反应器在存在或不存在促血管生成刺激因子VEGF和TGF-β1的情况下进行灌注时，可提供生理性间质流。我们通过模拟生物反应器腔室内单个三维微环境的模型确定了动态条件下应应用的参数。我们计算了作用在内皮细胞上的流体速度和壁面剪应力以及氧浓度分布，并选择了最适合维持真皮生理条件的流速。实验结果表明，所开发的平台作为血管生成的三维动态模型是有效的。这是第一项涉及化学刺激三维共培养以成功模拟生理性真皮血管周围微环境的实验和计算相结合的研究。
