Fibroblast spheroids were reseeded on TCPS after chitosan treatment.

<p>(a) SA-β-gal staining of PD48-Cd3-PD2 cells. Scale bar = 200 μm (b) The percentage of PD50 and PD48-Cd3-PD2 cells stained for SA-β-gal. At least 400 cells were calculated from ten randomly selected fields for each case. **p<0.01. (c) BrdU incorporation assay of PD50 and PD48-Cd3-PD2 cells (n = 4). *p<0.05. (d) Cell cycle (PI staining) analysis of PD52 and PD48-Cd3-PD2 cells. (e) The PD curve with and without chitosan treatment (n = 3). Red arrows indicate PD48 (1st treatment) and PD70 (2nd treatment) cells were seeded on chitosan for 3 days and reseeded on TCPS for serial passages.