Cardiac Fibroblast-Derived 3D Extracellular Matrix Seeded with Mesenchymal Stem Cells as a Novel Device to Transfer Cells to the Ischemic Myocardium

Demonstrate a novel manufacturing method to generate extracellular matrix scaffolds from cardiac fibroblasts (CF-ECM) as a therapeutic mesenchymal stem cell-transfer device. Rat CF were cultured at high-density (~1.6 × 10⁵/cm²) for 10-14 days. Cell sheets were removed from the culture dish by incubation with EDTA and decellularized with water and peracetic acid. CF-ECM was characterized by mass spectrometry, immunofluorescence and scanning electron microscopy. CF-ECM seeded with human embryonic stem cell derived mesenchymal stromal cells (hEMSCs) were transferred into a mouse myocardial infarction model. 48 h later, mouse hearts were excised and examined for CF-ECM scaffold retention and cell transfer. CF-ECM scaffolds are composed of fibronectin (82%), collagens type I (13%), type III (3.4%), type V (0.2%), type II (0.1%) elastin (1.3%) and 18 non-structural bioactive molecules. Scaffolds remained intact on the mouse heart for 48 h without the use of sutures or glue. Identified hEMSCs were distributed from the epicardium to the endocardium. High density cardiac fibroblast culture can be used to generate CF-ECM scaffolds. CF-ECM scaffolds seeded with hEMSCs can be maintained on the heart without suture or glue. hEMSC are successfully delivered throughout the myocardium.