Figure 1. The role exerted by chitosan in cell activity, apoptosis, and the cell cycle of orbital fibroblasts. A: Chemical production of chitosan. Cell activity was detected using the Cell Counting Kit-8 (CCK-8) after the orbital fibroblasts were treated with various concentrations of chitosan for 24 h (B) and 72 h (C). Percentage of apoptosis (D) and cells in the S phase (E) in orbital fibroblasts treated with various concentrations of chitosan for 24 h. Cell activity, percentage of apoptosis, and cells in the S phase were not influenced by chitosan at the 0.01 and 0.1 mg/ml concentrations. Data are presented as the mean ± standard deviation (SD), **p<0.01 and *p<0.05 for comparison with chitosan-treated and control orbital fibroblasts. The experiments in this figure were repeated three times, and similar results were obtained.