Study on the viscoelastic properties of gels from the extra-cellular matrix of decellularized tissue for therapeutic applications in cardiac and parenchymal tissue

健康领域，包括外科手术和再生医学，需要允许患者周围组织中的健康细胞迁移、保留和生长的材料。以凝胶和水凝胶的形式，这些材料被认为是支架结构。它们可以直接(不需要手术)注射到需要治疗的病理部位，或者模压或打印，然后使用传统手术植入。在任何情况下，这些高水合材料的弹性和粘性特性对于调节凝胶和生物特性是必不可少的。目前，通过整合细胞使这些材料细胞化的能力是该领域的下一个前沿。对纤维化样品的表征将使开发凝胶成为可能，当植入这种凝胶时，将能够再生和取代疾病组织的功能。在拟议的项目中，第一个目标是开发一种用于纤维化水凝胶的非接触式粘弹性表征的新型样品夹持器，该样品夹持器将与Rheolution开发的创新和独特的流变学设备一起使用。其次，由于TIsegrap的存在，以及他们在从动物组织中提取的脱细胞细胞外基质中配制水凝胶方面的专业知识，将使用Rhesion开发并在第一个目标框架内验证的样品保持器，优化凝胶的组成，刺激从人类细胞中招募和再生，用于修复和再生心脏或实质器官的缺陷。ULaval生物材料和生物工程实验室的独特专业技术，结合了对所开发凝胶的表面性质的改性和力学表征，构成了对这些纤维素化凝胶进行表征的基石。最后，第三个目标是探索开发一种新的体外模型的可能性，该模型基于所开发的Rhesion样品架和组织接枝水凝胶。

The field of health, including surgery and regenerative medicine, requires materials allowing the migration, retention and growth of healthy cells from the surrounding tissues of the patient. In the form of gels and hydrogels, these materials are considered scaffold structures. They can be injected directly (without surgery) into the pathological site requiring treatment, or molded or printed, and then implanted using conventional surgery. In any case, the elastic and viscous properties of these highly hydrated materials are essential in order to modulate the gelation and the biological properties. Currently, the ability to cellularize these materials, by integrating cells, is the next frontier in this field. The characterization of cellularized samples would make it possible to develop gels which, when implanted, would be able to regenerate and replace the functions of diseased tissues. In the proposed project, the first objective consists in the development of a novel sample holder for the contactless viscoelastic characterization of cellularized hydrogels to be used with the innovative and unique theological equipment developed by Rheolution. Second, thanks to the presence of Tissuegraft, and their expertise in formulating hydrogels from decellularized extracellular matrix extracted from animal tissues, will be the optimization of the composition of a gel stimulating recruitment and regeneration from human cells for the repair and regeneration of defects in cardiac or parenchymal organs, using the sample holder developed by Rheolution and validated within the framework of the 1st objective. The unique expertise at the Biomaterials and Bioengineering Laboratory of ULaval, combining the modification of surface properties and the mechanical characterization of the gels developed, constitutes the keystone to allow the characterization of these cellularized gels. Finally, the third objective is to explore the potential for the development of a new in vitro model based on the developed Rheolution sample holder and Tissuegraft hydrogels.