Akins R E, Boyce R A, Madonna M L, Schroedl N A, Gonda S R, McLaughlin T A, Hartzell C R
Department of Research, Alfred I. duPont Hospital for Children, Alfred I. duPont Institute of the Nemours Foundation, Wilmington, Delaware 19899, USA.
Tissue Eng. 1999 Apr;5(2):103-18. doi: 10.1089/ten.1999.5.103.
The mammalian heart does not regenerate in vivo. The heart is, therefore, an excellent candidate for tissue engineering approaches and for the use of biosynthetic devices in the replacement or augmentation of defective tissue. Unfortunately, little is known about the capacity of isolated heart cells to re-establish tissue architectures in vitro. In this study, we examined the possibility that cardiac cells possess a latent organizational potential that is unrealized within the mechanically active tissue but that can be accessed in quiescent environments in culture. In the series of experiments presented here, total cell populations were isolated from neonatal rat ventricles and recombined in rotating bioreactors containing a serum-free medium and surfaces for cell attachment. The extent to which tissue-like structure and contractile function were established was assessed using a combination of morphological, physiological, and biochemical techniques. We found that mixed populations of ventricular cells formed extensive three-dimensional aggregates that were spontaneously and rhythmically contractile and that large aggregates of structurally-organized cells contracted in unison. The cells were differentially distributed in these aggregates and formed architectures that were indistinguishable from those of intact tissue. These architectures arose in the absence of three-dimensional cues from the matrix, and the formation of organotypic structures was apparently driven by the cells themselves. Our observations suggest that cardiac cells possess an innate capacity to re-establish complex, three-dimensional, cardiac organization in vitro. Understanding the basis of this capacity, and harnessing the organizational potential of heart cells, will be critical in the development of tissue homologues for use in basic research and in the engineering of biosynthetic implants for the treatment of cardiac disease.
哺乳动物的心脏在体内不会再生。因此，心脏是组织工程方法以及使用生物合成装置替代或增强有缺陷组织的理想候选对象。不幸的是，对于分离的心脏细胞在体外重新建立组织结构的能力，人们了解甚少。在本研究中，我们探讨了一种可能性，即心脏细胞具有潜在的组织形成潜力，这种潜力在机械活跃的组织中未被实现，但在培养的静止环境中可以被激发。在本文呈现的一系列实验中，从新生大鼠心室中分离出完整的细胞群体，并在含有无血清培养基和细胞附着表面的旋转生物反应器中进行重组。使用形态学、生理学和生物化学技术相结合的方法，评估组织样结构和收缩功能的建立程度。我们发现，混合的心室细胞群体形成了广泛的三维聚集体，这些聚集体能够自发且有节律地收缩，并且结构有序的大聚集体能够同步收缩。细胞在这些聚集体中呈差异化分布，并形成了与完整组织难以区分的结构。这些结构在没有来自基质的三维线索的情况下出现，而且器官样结构的形成显然是由细胞自身驱动的。我们的观察结果表明，心脏细胞具有在体外重新建立复杂的三维心脏组织结构的内在能力。了解这种能力的基础，并利用心脏细胞的组织形成潜力，对于开发用于基础研究的组织同源物以及用于治疗心脏病的生物合成植入物的工程设计至关重要。
