Abstract 19359: Local Injection of First Trimester Human Umbilical Cord Perivascular Cells (FTM-HUCPVCs) After Myocardial Infarction Increases Extracellular Matrix Processing Activity, Vascular Density and Blood Vessel Size Within the Infarct Scar
Introduction: During myocardial infarction (MI) the ischemic heart muscle loses a substantial number of cells, and a poorly vascularised fibrotic scar forms. We previously showed that local injections of first trimester human umbilical cord perivascular cells (FTM-HUCPVCs) diminish scar tissue and significantly improve cardiac output after MI in rats.
Hypothesis: We hypothesised that FTM-HUCPVCs induce superior tissue remodeling and revitalization post-MI by 1: elevating ECM processing gelatinase/collagenase activity, 2: increasing blood vessel penetration and revascularisation of the infarct scar.
Methods: MI was induced by left ventricular coronary artery ligation on 8 week old Foxrnu rats. 1 week post-MI, FTM-HUCPVC, term HUCPVC or human BMSC (n=6 per group) were injected into the injured myocardium (3X106 cells each). Histology was performed 2 weeks after cell implantation. In situ gelatinase activity was assessed by fluorescent gelatinase substrate (DQ gelatin). Vascular density was assessed by endothelium-specific fluorescent isolectin (IB4). Fluorescent microscopy images were quantified for vascular density and blood vessel size by ImageJ (6 sections per heart, 9 random fields per section). Statistical analysis: ANOVA.
Results: FTM-HUCPVC treatments resulted in increased fluorescent gelatine signal in the scar tissue of post-MI rat hearts (A) and displayed gelatinase activity in a structured pattern. Vascular density of the ischemic myocardium (B) was significantly higher (p<0.01) in FTM- and term HUCPVC treated hearts compared to untreated (C). BMSC treatment did not result in significant improvement. Median area of blood vessel cross-sections was the highest after FTM-HUCPVC treatment and significantly higher (p<0.01) than of BMSC treated hearts.
Conclusion: FTM-HUCPVCs induce superior ECM processing and revascularisation in scar tissue after myocardial infarction compared with later gestation HUCPVCs and BMSCs.
Author Disclosures: P. Szaraz: None. A. Lucato: None. S. Li: None. J. Wu: None. A. Gauthier-Fisher: None. R. Li: None. C.L. Librach: None.
- © 2015 by American Heart Association, Inc.