Cardiac differentiation of cardiosphere-derived cells in scaffolds mimicking morphology of the cardiac extracellular matrix

Abstract

Stem cell therapy has the potential to regenerate heart tissue after myocardial infarction (MI). The regeneration is dependent upon cardiac differentiation of the delivered stem cells. We hypothesized that timing of the stem cell delivery determines the extent of cardiac differentiation as cell differentiation is dependent on matrix properties such as biomechanics, structure and morphology, and these properties in cardiac extracellular matrix (ECM) continuously vary with time after MI. In order to elucidate the relationship between ECM properties and cardiac differentiation, we created an in vitro model based on ECM-mimicking fibers and a type of cardiac progenitor cell, cardiosphere-derived cells (CDCs). A simultaneous fiber electrospinning and cell electrospraying technique was utilized to fabricate constructs. By blending a highly soft hydrogel with a relatively stiff polyurethane and modulating fabrication parameters, tissue constructs with similar cell adhesion property but different global modulus, single fiber modulus, fiber density and fiber alignment were achieved. The CDCs remained alive within the constructs during a 1 week culture period. CDC cardiac differentiation was dependent on the scaffold modulus, fiber volume fraction and fiber alignment. Two constructs with relatively low scaffold modulus, ~50–60 kPa, most significantly directed the CDC differentiation into mature cardiomyocytes as evidenced by gene expressions of cardiac troponin T (cTnT), calcium channel (CACNA1c) and cardiac myosin heavy chain (MYH6), and protein expressions of cardiac troponin I (cTnI) and connexin 43 (CX43). Of these two low-modulus constructs, the extent of differentiation was greater for lower fiber alignment and higher fiber volume fraction. These results suggest that cardiac ECM properties may have an effect on cardiac differentiation of delivered stem cells.

Regulating myogenic differentiation of mesenchymal stem cells using thermosensitive hydrogels

“…Following gelation at 37°C for 20 min, cell culture medium was added. After 1, 7, and 14 days of culture under normal tissue culture conditions (20% O 2 and 5% CO 2 ), dsDNA (for live cells) content in the hydrogels was measured by PicoGreen assay kit (Invitrogen) following the protocol reported previously [52].…”

Thermosensitive and Highly Flexible Hydrogels Capable of Stimulating Cardiac Differentiation of Cardiosphere-Derived Cells under Static and Dynamic Mechanical Training Conditions

“…We have demonstrated that CDCs differentiated into cardiomyocytes in fibrous scaffold based on poly(ester urethane)urea and PNIPAAm hydrogel, and the most significant differentiation was in scaffold with elastic modulus of ~50–60 kPa. 62 Besides CDCs, other cell types also showed matrix modulus-driven cardiac differentiation. MSCs had the highest cardiac differentiation in 65 kPa hydrogel based on NIPAAm, N -acryloxysuccinimide, AAc, and poly(trimethylene carbonate)-hydroxyethyl methacrylate.…”

Cells, Scaffolds and Their Interactions in Myocardial Tissue Regeneration

“…Hence, biosimulation of cardiac microenvironment into the scaffolds is an important matter to determine the output of heart tissue engineering. Specifically, all of the cardiac microenvironment components including growth factors [Lin et al, ; Lisi et al, ], decellularized tissue matrices [Xu et al, ] and synthetic polymer scaffolds [Parrag et al, ; Crowder et al, ] are as key matters to achieve the effective injured heart masculinization and revascularization. Moreover, preserving the survival and function of the seeded cell against the low oxygen and nutrient condition [Kawamura et al, ] is a crucial feature for heart tissue engineering efficiency which it has a close relationship with biosimulation of the cardiac microenvironment.…”