Augmentation of regenerative potential of mesenchymal stem cells by granulocyte-colony stimulating factor (G-CSF) induced mobilization

Objectives: The development of a safe and efficient method for isolation of mesenchymal stem cell (MSC) subsets is essential for optimal stem cell therapy. The potential utility of granulocyte-colony stimulating factor (G-CSF) induced mobilization method has been demonstrated in isolation of MSC subsets from dental pulp. The mobilized dental pulp stem cells (MDPSCs) were enriched for MSC subsets with higher regenerative potential compared with colony-derived dental pulp stem cells (DPSCs). This investigation aimed to examine the efficacy of the G-CSF induced mobilization method for isolation of MSC subsets from other tissues such as bone-marrow and adipose tissue.
Methods: The pulp tissue from premolar teeth, the bone marrow and adipose tissue were isolated from the same individual porcine mandible. Then, colony-forming primary cells, named DPSCs, BMSCs and ADSCs, were cultured from each tissue. The subsets of DPSCs, BMSCs and ADSCs (MDPSCs, MBMSCs and MADSCs) were further isolated by G-CSF induced stem cell mobilization. The stem cell properties, trophic effects, and regenerative potential of mobilized MSCs were compared with those of corresponding colony-derived MSCs, respectively.
Results: The mobilized MSCs represented significantly higher rate of CXCR4⁺ and G-CSFR⁺ cells, higher proliferation and migratory activity and higher expression of Sox2 than corresponding colony-derived MSCs. Trophic effects of the mobilized MSCs, including enhanced proliferation, migration, anti-apoptosis, angiogenesis and neurite extension, were also higher compared to the colony-derived MSCs, correlating with higher expression of trophic factors. Each of mobilized MSCs induced higher angiogenesis/vasculogenesis and pulp regeneration in ectopic tooth transplantation model.
Conclusions: The G-CSF induced mobilization method for isolation of MSC subsets is efficient and appears to be a significant advance independent of tissue origin.