Proliferation of dental follicle-derived cell populations in heat-stress conditions

作者：Yao S^*; Gutierrez D L; He H; Dai Y; Liu D; Wise G E

来源：Cell Proliferation, 2011, 44(5): 486-493.

DOI：10.1111/j.1365-2184.2011.00778.x

Objectives: Isolation and purification of adult stem cells (ASC) are a great challenge. Our objectives were to determine whether ASC are more heat-tolerant than non-stem cells, and to explore if ASC could be enriched by heat-stress treatments.
Materials and methods: Rat dental follicle cells were cultured in a variety of media to obtain either a heterogeneous cell population (H-DFC) consisting of stem cells and non-stem cells, or a homogenous cell population (DFC) containing non-stem cells only. Real-time RT-PCR was conducted to compare expression of heat-shock proteins (HSPs) between the two populations. To study heat tolerance, H-DFC and DFC were incubated under heat-stress conditions and cell proliferation was evaluated by alamar blue reduction assay. Furthermore, cells resulting from heat-stress treatments were evaluated for differentiation capability and expression of stem cell markers.
Results: H-DFC expressed higher levels of HSP110, HSP70s and HSP27s than did DFC. H-DFC increased levels of proliferation at 40 degrees C compared to controls grown at 37 degrees C; no significant reduction in proliferation occurred at temperatures below 40.5 degrees C. In contrast, DFC showed significant reduction in proliferation under all heat-stress treatments. Heat-stressed H-DFC had increased differentiation capability and increased expression of stem cell markers.
Conclusion: Stem cells appear to be more tolerant to heat stress than non-stem cells. Incubation of a heterogeneous cell population in heat-stress conditions resulted in increased stem cell numbers.

• 出版日期2011-10