Granulocytes-colony stimulating factor (G-CSF) has a stem cell mobilizing capacity and favorable effects on ventricular remodeling following a myocardial infarction. G-CSF based stem cell therapy has shown favorable results in animal studies. However, the long term outcome of G-CSF based stem cell therapy in clinical trial remains unknown. Herein, we report the six month follow up results of two different G-CSF based stem cell therapy strategies.

We compared the intra-coronary infusion of mobilized peripheral blood stem cells (PBSCs) with G-CSF (n=10), mobilization with G-CSF alone (n=16) and control percutaneous coronary intervention (PCI) alone (n=15) in patients following a myocardial infarction.

At the six month follow up evaluations, the intra-coronary cell infusion was found to have improved the left ventricular (LV) systolic function and remodeling compared to the baseline, whereas G-CSF alone showed no improvement. Therefore, an intra-coronary cell infusion showed better improvements in the LV systolic function (p<0.001) and remodeling (p<0.01) than G-CSF alone. Cell infusion also showed better results than the control PCI alone group, but these did not reach statistical significance with the limited number of patients used in this study. Patients who received G-CSF administration showed a modest increase of binary restenosis (p=0.185) and a greater late loss in the minimal luminal diameter at the 6 month follow up than the control group.

An intra-coronary cell infusion of mobilized PBSCs using G-CSF was found to be better than G-CSF alone at the six month follow up evaluation. G-CSF was also found to increase the potential risk of restenosis, especially when administered prior to stent implantation. The efficacy of an intra-coronary infusion of mobilized PBSCs should be evaluated in a large randomized controlled trial.