Use of granulocyte-colony stimulating factor during acute myocardial infarction to enhance bone marrow stem cell mobilization in humans: Clinical and angiographic safety profile

Aims: There is increasing evidence that stem cell (SC) mobilization to the heart and their differentiation into cardiac cells is a naturally occurring process. We sought to assess the safety and feasibility of granulocyte-colony stimulating factor (G-CSF) administration in humans to enhance SC mobilization and left ventricle (LV) injury repair during myocardial infarction (MI). Methods and results: Twenty patients with STEMI (mean age, 61 ± 10 years), of whom 14 were submitted to primary percutaneous coronary intervention, were randomized to G-CSF (5 μg/kg/day s.c. for 4 consecutive days) or placebo. At entry and then at months 3 and 6, ^99mTc-sestamibi gated-SPECT was performed to estimate extension of perfusion defect (PD) and LV function. The study drug was well tolerated and induced a significant increase of white blood count, CD34⁺ cells, and CD34⁺ cells coexpressing AC133 and VEGFR-2. At follow-up, treated and placebo groups did not differ for the angiographic coronary late loss and showed a similar pattern of PD recovery, whereas in the former at 6 months LVEF and especially LVEDV tended to be relatively higher (P = 0.068) and lower (P = 0.054), respectively. Conclusion G-CSF administration in acute MI patients was feasible and did not lead to any clinical or angiographic adverse events and resulted in CD34⁺ and CD34⁺AC133⁺VEGFR2⁺ cell mobilization.