Minuth Will W, Schumacher Karl, Strehl Raimund
Department of Molecular and Cell Anatomy, University of Regensburg, Germany.
Biomed Mater Eng. 2005;15(1-2):51-63.
In the organism epithelia perform perfect barrier functions. Strong rheological and mechanical influences constitute the normal environment of this tissue throughout life. Most epithelia are exposed to different fluids at the luminal and basal sides. To obtain realistic information about tissue development in modern biomaterial testing and tissue engineering it is necessary to mimick the natural environment of epithelia. Cultured cells are brought in contact with an artificial extracellular matrix to determine whether proper development into a functional epithelium occurs. As under natural conditions the cultures have to withstand mechanical and fluid stress over a prolonged period of time in close contact to a selected biomaterial. However, development of tissue-specific features such as polarization, tightness and transport under in vitro conditions will only occur, if the biomaterial and the culture conditions support tissue development. Leakage, edge damage and pressure differences during culture have to be avoided so that the natural functions of the growing epithelium can develop. Our aim is to generate functional epithelia derived from renal explants containing stem cells, which are microsurgically isolated and placed into specific O-ring carriers for optimal handling. The cells develop in combination with a collagenous matrix from an embryonic into a functional collecting duct (rCD) epithelium. To achieve optimal culture conditions the tissue is placed in a gradient culture container. A typical environment can be simulated by superfusing different culture media at the luminal and basal sides. Within days epithelia growing inside the gradient container build up a physiological barrier, which is maintained during the whole culture period. The described method allows to investigate the influence of new biomaterials over prolonged periods of time.
在生物体中，上皮组织发挥着完美的屏障功能。强大的流变学和力学影响构成了该组织一生的正常环境。大多数上皮组织在管腔侧和基底侧暴露于不同的流体中。为了在现代生物材料测试和组织工程中获得有关组织发育的真实信息，有必要模拟上皮组织的自然环境。将培养的细胞与人工细胞外基质接触，以确定是否能正常发育成功能性上皮组织。在自然条件下，培养物必须在与选定的生物材料紧密接触的情况下长时间承受机械和流体应力。然而，只有当生物材料和培养条件支持组织发育时，体外条件下组织特异性特征（如极化、紧密性和运输）的发育才会发生。培养过程中必须避免渗漏、边缘损伤和压力差异，以便生长中的上皮组织的自然功能得以发展。我们的目标是从含有干细胞的肾外植体中生成功能性上皮组织，这些肾外植体通过显微手术分离并放置在特定的O形环载体中以便于最佳操作。细胞与胶原基质结合，从胚胎期发育成功能性集合管（rCD）上皮组织。为了实现最佳培养条件，将组织置于梯度培养容器中。通过在管腔侧和基底侧灌注不同的培养基可以模拟典型的环境。在几天内，在梯度容器内生长的上皮组织形成生理屏障，该屏障在整个培养期间得以维持。所描述的方法允许在较长时间内研究新型生物材料的影响。
