Stem cells can be defined as units of biological organization that are responsible for the development and the regeneration of organ and tissue systems. They are able to renew their populations and to differentiate into multiple cell lineages. Therefore, these cells have great potential in advanced tissue engineering and cell therapies. When seeded on synthetic or nature-derived scaffolds in vitro, stem cells can be differentiated towards the desired phenotype by an appropriate composition, by an appropriate architecture, and by appropriate physicochemical and mechanical properties of the scaffolds, particularly if the scaffold properties are combined with a suitable composition of cell culture media, and with suitable mechanical, electrical or magnetic stimulation. For cell therapy, stem cells can be injected directly into damaged tissues and organs in vivo. Since the regenerative effect of stem cells is based mainly on the autocrine production of growth factors, immunomodulators and other bioactive molecules stored in extracellular vesicles, these structures can be isolated and used instead of cells for a novel therapeutic approach called “stem cell-based cell-free therapy”. There are four main sources of stem cells, i.e. embryonic tissues, fetal tissues, adult tissues and differentiated somatic cells after they have been genetically reprogrammed, which are referred to as induced pluripotent stem cells (iPSCs). Although adult stem cells have lower potency than the other three stem cell types, i.e. they are capable of differentiating into only a limited quantity of specific cell types, these cells are able to overcome the ethical and legal issues accompanying the application of embryonic and fetal stem cells and the mutational effects associated with iPSCs. Moreover, adult stem cells can be used in autogenous form. These cells are present in practically all tissues in the organism. However, adipose tissue seems to be the most advantageous tissue from which to isolate them, because of its abundancy, its subcutaneous location, and the need for less invasive techniques. Adipose tissue-derived stem cells (ASCs) are therefore considered highly promising in present-day regenerative medicine.

干细胞可以定义为负责器官和组织系统发育和再生的生物组织单位。他们能够更新其种群并分化为多种细胞谱系。因此，这些细胞在先进的组织工程和细胞治疗中具有巨大的潜力。当体外接种在合成或自然来源的支架上时可以通过适当的组成，适当的结构，以及适当的支架理化性质和机械特性将干细胞向所需的表型分化，特别是如果将适当的支架特性与合适的细胞培养基组成和适当的细胞培养基相结合的话机械，电或磁刺激。对于细胞疗法，可以将干细胞直接注射到体内受损的组织和器官中。由于干细胞的再生作用主要基于生长在细胞外囊泡中的生长因子，免疫调节剂和其他生物活性分子的自分泌产生，因此这些结构可以被分离并替代细胞，用于一种称为“基于干细胞的细胞”的新型治疗方法。 -免费疗法”。干细胞有四种主要来源，即经过基因重编程后的胚胎组织，胎儿组织，成年组织和分化的体细胞，它们被称为诱导多能干细胞（iPSC）。尽管成体干细胞的效能比其他三种干细胞低，即它们只能分化为有限数量的特定细胞类型，这些细胞能够克服伴随胚胎和胎儿干细胞应用以及与iPSC相关的突变效应的道德和法律问题。而且，成体干细胞可以自体形式使用。这些细胞实际上存在于生物体的所有组织中。然而，由于脂肪组织的丰度，皮下位置以及对侵入性较小技术的需求，脂肪组织似乎是与之分离的最有利的组织。因此，在当今的再生医学中，源自脂肪组织的干细胞（ASC）被认为很有前途。脂肪组织似乎是分离它们的最有利组织，因为它的丰度，皮下位置以及对侵入性较小技术的需求。因此，在当今的再生医学中，源自脂肪组织的干细胞（ASC）被认为很有前途。脂肪组织似乎是分离它们的最有利组织，因为它的丰度，皮下位置以及对侵入性较小技术的需求。因此，在当今的再生医学中，源自脂肪组织的干细胞（ASC）被认为很有前途。