Abstract:

BACKGROUND: The muscle-derived stem cells transplanted into the body of the animals can repair the defects of bone, muscle, cartilage and neural system. An efficient and safe labeling method is needed to understand the migration, proliferation and differentiation of the cells.
OBJECTIVE: To observe the effect of 5-bromodeoxyuridine (Brdu) labeling of muscle-derived stem cells in vitro, to study the optimal dosage and timing.
METHODS: Muscle-derived stem cells from Sprague Dawley rats were isolated in vitro using differential adhesion method. The second passage of cells was counted and identified by immunocytochemical staining. The cells were labeled by BrdU at 5, 10, 15, 20 μmol/L to identify the optimal BrdU concentration. Immunocytochemistry was performed to calculate the labeling index. By MTT testing and trypan blue testing, we surveyed the influence of BrdU on the growth of muscle-derived stem cells. 
RESULTS AND CONCLUSION: Immunocytochemical staining results showed positive expression of Desmin in MDSCs with the percentage of (85.7±6.0)%. The viability and proliferation between the group labeled by BrdU and the control group were similar (P > 0.05). The rate of the living cells labeled by BrdU was (92.3±2.1)%. The labeling rate was better in the 10, 15, 20 μmol/L groups compared with 5 μmol/L group. The optimal dosage was 10 μmol/L, and the optimal time was 3 days, and the labeling index was (70.9±4.5)% with no significant change over time. It was proved that after labeled by BrdU, no difference in the viability and proliferation was found in muscle-derived stem cells, and the labeling index can come up to the required standards of the transplantation.