Application of Multichannel Collagen Gels in Construction of Epithelial Lumen-like Engineered Tissues

Introduction of epithelial lumen-like structures such as blood and lymphatic vessels, as well as renal tubules, is a prerequisite for successful construction and function of artificially engineered giant tissues. Here, we demonstrate a methodology for construction of various epithelial lumen-like structures by using multichannel collagen gels (MCCGs). MCCGs were prepared and used as template scaffolds for constructing epithelial lumen structures in a controlled fashion. The effect of NaCl concentration on the multichannel structure of MCCGs was investigated by using confocal laser scanning microscopy along with fluorescent staining. The channel diameter increased with increasing NaCl concentrations in the collagen solution and the phosphate buffer solution. In contrast, the channel number decreased with increasing NaCl concentrations. Engineered tissues with various lumen-like structures were constructed by seeding and culturing Madin-Darby canine kidney cells on MCCGs. The diameter of the lumen and the number of lumens per unit area were controllable by regulating the multichannel structure of cylindrical MCCG. We believe that our methodology for the construction of engineered tissues possessing epithelial lumen-like structures will prove helpful in regeneration of giant tissues with various hierarchical structures.