Fig. 4.

Identification of the presence of integrin heterodimers interacting with fibronectin, laminin, tenascin C and vitronectin on the cell membrane of undifferentiated outbred ICR mouse SSCs. A 96-well tissue culture plates was coated with 0, 40, or 80 μg/ml fibronectin (A), 0, 200, or 400 μg/ml laminin (B), 0, 20, or 40 μg/ml tenascin C (C), and 0, 5, or 10 μg/ml vitronectin (D). Subsequently, SSC population were prepared by sorting testicular cells retrieved enzymatically from testis derived from ICR mice using a MACS technique based on anti-Thy1 antibody. Then, 1×10⁴ cells in SSC population were resuspended in SSC culture medium and plated in each well. After incubation for 2 h at 37℃, adherent cells were stained with crystal violet, and the adhesion level was quantified using a microplate reader. The percentage of maximum adhesion is represented as the optical density of cells plated on ECM protein-free plates. Mouse SSCs cultured on fibronectin-, laminin-, tenascin C- and vitronectin-coated culture plates had significantly higher levels of adhesion than those on ECM protein-free culture plates. However, increasing concentrations of ECM on the culture plates did not induce a significant improvement of mouse SSC adhesion levels. All of the data shown are means±standard deviation of three independent experiments. *p<0.05.