Hybrid Gel Composed of Native Heart Matrix and Collagen Induces Cardiac Differentiation of Human Embryonic Stem Cells without Supplemental Growth Factors

Abstract

Our goal was to assess the ability of native heart extracellular matrix (ECM) to direct cardiac differentiation of human embryonic stem cells (hESCs) in vitro. In order to probe the effects of cardiac matrix on hESC differentiation, a series of hydrogels was prepared from decellularized ECM from porcine hearts by mixing ECM and collagen type I at varying ratios. Maturation of cardiac function in embryoid bodies formed from hESCs was documented in terms of spontaneous contractile behavior and the mRNA and protein expression of cardiac markers. Hydrogel with high ECM content (75% ECM, 25% collagen, no supplemental soluble factors) increased the fraction of cells expressing cardiac marker troponin T, when compared with either hydrogel with low ECM content (25% ECM, 75% collagen, no supplemental soluble factors) or collagen hydrogel (100% collagen, with supplemental soluble factors). Furthermore, cardiac maturation was promoted in high-ECM content hydrogels, as evidenced by the striation patterns of cardiac troponin I and by upregulation of Cx43 gene. Consistently, high-ECM content hydrogels improved the contractile function of cardiac cells, as evidenced by increased numbers of contracting cells and increased contraction amplitudes. The ability of native ECM hydrogel to induce cardiac differentiation of hESCs without the addition of soluble factors makes it an attractive biomaterial system for basic studies of cardiac development and potentially for the delivery of therapeutic cells into the heart.

Endogenous Optical Signals Reveal Changes of Elastin and Collagen Organization During Differentiation of Mouse Embryonic Stem Cells

“…18 Similarly, the ECM derived from cardiac tissue has been shown to enhance cardiomyocyte maturation of rat cardiac progenitor cells 59 and human embryonic stem cells. 60 Together with our studies, these results suggest that ColI might have a dampening effect on early differentiation of cardiomyocytes or it may impact on the growth and division of cardiomyocytes or their precursors through a mechanism we do not yet understand. The imaging techniques we describe here, because they can be performed on live cultures without manipulation required of staining protocols, could be used to better understand the relationship between ECM components and differentiation.…”

Stromal Cells in Dense Collagen Promote Cardiomyocyte and Microvascular Patterning in Engineered Human Heart Tissue

“…[2][3][4][5][6] An attractive alternative is the tissue engineering approach, where three-dimensional (3D) structural control and tissue maturation before implantation are possible. 7 Many groups have had considerable success forming contractile cardiac constructs within native soft biological hydrogels, such as fibrin, 8,9 collagen, [10][11][12] and decellularized heart matrix, 13 as well as in scaffold-free conditions. 14,15 Engineering large scale cardiac tissues, however, continues to be hindered by a lack of vasculature and poor structural and functional maturation of stem cell-derived cardiomyocytes.…”

Hydrogels for cardiac tissue engineering

“…[79][80][81] Recently, both 2D and 3D cardiac patches were fabricated by differentiating human ESCs into cardiomyocytes in fibrin-based matrices. 79 After 2 weeks of culture, highly functionalized cardiac tissues were formed by the alignment of ESCs in microfabricated hydrogel matrices containing staggered elliptical pores (Figure 4).…”

“…80 Human ESC-derived cardiomyocytes were encapsulated in hybrid hydrogels composed of decellularized cardiac ECM from porcine heart and collagen type I. It was found that the population of ESCs that express troponin T increased when a hydrogel with higher concentration of ECM was used.…”

“…In addition, hydrogels with a high ECM content promoted the function and contractile activities of cardiac cells as evidenced by higher expression of troponin I and connexin-43 compared with low-concentration ECM gels or pure collagen gels. 80 Similarly, functional human heart tissue was engineered by using human ESC-derived cardiomyocytes in a fibrin gel. 84 Highly organized and oriented networks of sarcomeres were formed within the hydrogel matrix.…”