2004 年 25 巻 2 号 p. 61-68
The purpose of this study was to investigate the behavior of L929 fibroblasts on substrates of different pore sizes and to find an appropriate pore size that allows them to differentiate into type 1 collagen synthesizing cells. The behavior of cultured fibroblasts on Millipore filters of 4 different pore sizes (1.2 μm, 3.0 μm, 5.0 μm and 8.0 μm) was compared morphologically. The expression of type 1 collagen mRNA was also analyzed by RT-PCR. The cell length was the greatest in the control group (without a filter) compared to the experimental groups cultured on filters at 3 days, however there were no significant differences among any of the groups at 7 days. At the ultrastructural level, small and fine cell processes had invaded the pores of filter membranes with pore sizes of 1.2 μm or 3.0 μm, while long and thick cell processes containing many organelles (some of them degenerated) had invaded the pores of filter membranes with pore sizes of 5.0 μm or 8 μm. The expression of type 1 collagen mRNA was the highest in cells cultured on membranes with 1.2 μm pores at 3 days but was not significantly changed among any of the groups at 7 days. This suggests that Millipore filters with a 1.2 μm pore size are the most suitable to allow L929 fibroblasts to express the phenotype for type 1 collagen synthesis at early time periods.