Feasibility study of TNF-α increasing bone marrow mesenchymal stem cell migration to ischemic tissues

Abstract

Objective To study the feasibility of TNF-α promoting migration of rat mesenchymal stem cells (MSCs) to local damaged tissues. Methods The MSCs was exposed to TNF-α at different concentrations and the expression rate of surface adheslon molecules and specific markers as well as their adhesion to endothelial cells were detected.Based on the above steps,the MSCs stimulated with the optimal concentration of TNF-α were obtained and were injected intravenously to the rats whose hindlimbs experienced ischemia damage.The rats were executed for achieving the muscle samples in the ischemic area,which were made into frozen section to count the number of MSCs. Results ( 1 ) Twenty-four hours after the TNF-o stimulation,the expression of adhesion molecule (VCAM-1) of MSCs increased in a concentration-dependent manner,while the expression of adhesion molecules (ICAM-1,L-Selectin and VLA4) of MSCs showed no significant changes.Besides,the expression rate of specific markers of MSCs was also obscure.(2) Exposed to 10 ng/ml TNF-o,MSCs presented an obviously increased ability in adhesion to the endothelial cells.(3) MSCs stimulated with 10 ng/ml TNF-α showed a larger number in the ischemia-damaged tissue of rat hindlimbs than that in the control group. Conclusion TNF-α at concentration of 10 ng/ml is effective within a short term in increasing VCAM-1 expression in rat MSCs and promoting the adhesion of MSCs to endothelial cells without affecting their character. Key words: Bone marrow; Stem cells; Cell adhesion molecules; Endothelial cells; Rats