in vitro evaluation of the biocompatibility and stability of fluorescent dil dye on mouse embryonic fibroblast cells

Background: there are few methods for cell labeling in basic studies of cell-migration, tissue engineering, and cell therapy. recent progress in cell trackers has led to an increasing number of clinical trials involving the treatment of various diseases based on cell transplantation. objectives: in this study, we investigated the effects of different concentrations of dii as a cell labeling dye on the viability and proliferation of mouse embryonic fibroblasts (mefs). methods: mefs were divided into two groups of control and experimental (treated with dil dye). we treated mefs with three concentrations of the dye and after 1, 5, 7 and 14 days, these cells were analyzed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (mtt) assay and 4’, 6-diamidino-2-phenylindole (dapi) staining. also, the stability of the dye in treated mefs was examined by immunofluorescence. results: our results showed that cell viability was significantly different between the groups that received dil at the concentrations of 1 and 2 g/ml and the control group. however, cell viability was not significantly different between the group that received dil (0.5 µg/ml) and the control group. conclusions: therefore, dil at concentrations higher than 0.5 µg/ml was toxic for mefs. we suggest that dil dye, which is concentration-dependent, can be used as a safe and stable fluorescent dye for cell labeling both in-vivo and in-vitro.