Introduction of Cells into Porous Poly-l-Lactic Acid Scaffolds Using Impregnation Techniques

Porous materials containing cells-prepared via cell seeding on scaffolds or gelation of cell-containing solutions-have been widely studied to investigate tissue regeneration and three-dimensional cultures. However, these methods cannot introduce cells into porous materials that have low water absorption or scaffolds that require cytotoxic solvents or processes for their production. In this study, first, three different impregnation treatments conditions (vacuum, pressure, and vacuum pressure impregnation: VPI) were applied to cell suspensions to evaluate the effect of each treatment on cells. Following all three treatments, fibroblasts adhered to the cell culture dish and proliferated in the same manner as untreated cells, which confirmed that the three impregnation treatments did not affect cell function. Second, cells were introduced into a poly-l-lactic acid (PLA) scaffold, which has low water absorption, using the same impregnation treatments. The PLA scaffolds subjected to the three impregnation treatments that exhibited a significantly greater amount of DNA than those subjected to immersion treatments and showed increasing amounts of DNA in the order vacuum treatment > VPI treatment > pressure treatment. Furthermore, the amount of DNA in the vacuum-treated and VPI-treated PLA scaffolds increased on the first, third, and fifth days of culture, and it was confirmed that the cells introduced into the PLA scaffolds proliferated. These results suggest that vacuum and VPI treatments may be useful methods for introducing cells into porous materials.