Abstract 943: In Vivo Assessment of Mesenchymal Stem Cells Fate Following Intracoronary Delivery
Background: Prior studies have alluded to the regenerative potential of cell-based therapy in myocardial infarction (MI) and have shown that adult mesenchymal stem cells (aMSC) represent a promising donor source. Mechanisms underlying therapeutic benefits still require further study. Hence, tracking the fate of stem cells remains a pivotal issue.
Methods: Using a swine (Yorkshire) model, cell injections into naïve (group1, n=2) vs infarcted myocardium (group 2, n=4) were compared. aMSC were isolated and expanded from the adherent cell fractions of collected bone marrow aspirates. MI was created by 60-minute balloon occlusion of the left anterior descending artery 3 days prior to cell injection. On the day of delivery, allogenic aMSC (20x106) were loaded with the near-infrared (NIR) fluorophore IR-786 (10 μM). Intracoronary injection into the infarct-related artery was performed via a standard over-the-wire balloon catheter. In vivo NIR fluorescence (open-chested) cell tracking was performed just prior to and for 60 minutes following cell delivery.
Results: Qualitative and quantitative assessments reveal that patterns of distribution of injected aMSC differ between infarcted and naïve myocardium (Figure⇓). At 60 minutes, relative to time 0, fluorescence signal intensities:
increased to 127.9±45.1% in group 1 (p= NS);
declined to 26.5%±3.0% in group 2 (p=0.0196) and
were significantly different between both groups.
aMSC delivery was well tolerated without complication.
Conclusion: In vivo assessment of aMSC reveals that cell distribution patterns differ following MI. This may have implication regarding homing and transmigration potential of injected aMSC.