Influence of EGF, TGFβ and bFGF on DPSC Proliferation

Objectives: Different growth factors could be detected in human dentin matrix. Previous studies show that bFGF increase cell proliferation, but prevent terminal differentiation of odontoblasts. Due to the stage-specific effects other recombinant growth factors can be substituted such as bFGF or EGF. TGFβ often is used to promote odontoblast-like cell differentiation and dentin formation of dental pulp cells.
Methods: The aim of the present studie was to investigate the effect of bFGF or EGF or TGFβ on proliferation of DPSC. DPSC were cultured in α-MEM supplemented with different concentrations of recombinant bFGF (10ng/ml), EGF (5ng/ml), TGFβ (10ng/ml) and EGF+TGFβ (15ng/ml). Medium was replaced daily. Thereafter RNA and protein was isolated at 24h, 48h and 72h. Ki67 was used As a marker for proliferating cells in qPCR and Western Blot analysis.
Results: The most potent proliferative effects on DPSC were reported for bFGF and EGF at 24h. Further treatment with both compounds resulted also in higher proliferation rates as compared with controls, however not so pronounced as 24 h. Treatment with TGFβ alone resulted in slightly increased proliferation of the cells. Combined treatment of the cells with EGF and TGFβ led to comparable proliferation rates as the treatment with both compounds alone, but with this advantage that we were able to induce both regenerative processes parallel.
Conclusions: In summary our results indicate that EGF may be used to increase the proliferation rates of cultured dental stem cells and compensate the affectation of TGFβ. Employment of EGF may be an effective alternative to bFGF treatment for maintenance and proliferation of human dental stem cells. Since these data are very promising, further investigations, especially the possible role of EGF in DPSC differentiation, should be elucidated.