Gene expression of single human mesenchymal stem cell in response to fluid shear

Abstract

Stem cell therapy may rely on delivery and homing through the vascular system to reach the target tissue. An opticaltweezer model has been employed to exert different levels of shear stress on a single non-adherent human bonemarrow-derived mesenchymal stem cell to simulate physiological flow conditions. A single-cell quantitative polymerasechain reaction analysis showed that collagen type 1, alpha 2 (COL1A2), heat shock 70-kDa protein 1A (HSPA1A) andosteopontin (OPN) are expressed to a detectable level in most of the cells. After exposure to varying levels of shearstress, there were significant variations in gene transcription levels across human mesenchymal stem cells derived fromfour individual donors. Significant trend towards upregulation of COL1A2 and OPN gene expression following shear wasobserved in some donors with corresponding variations in HSPA1A gene expression. The results indicate that shearstress associated with vascular flow may have the potential to significantly direct non-adherent stem cell expressiontowards osteogenic phenotypic expression. However, our results demonstrate that these results are influenced by theselection process and donor variability. © The Author(s) 2012.