Résumé
Cardiac tissue engineering could be useful for replacement and/or repair of diseased or malformed cardiac tissue. The creation of functional, biocompatible contractile tissues, however, remains challenging. These investigators report a novel method of engineering a highly effective collagen-cell scaffold based on arginine–glycine–aspartic acid–serine peptides cross-linked to a clinically approved collagen matrix.
Background
Cardiac tissue engineering might be useful in treatment of diseased myocardium or cardiac malformations. The creation of functional, biocompatible contractile tissues, however, remains challenging. We hypothesized that coupling of arginine–glycine–aspartic acid–serine (RGD
+
) adhesion peptides would improve cardiomyocyte viability and differentiation and contractile performance of collagen-cell scaffolds.
Methods
Clinically approved collagen scaffolds were functionalized with RGD
+
cells and seeded with cardiomyocytes. Contractile performance, cardiomyocyte viability and differentiation were analyzed at days 1 and 8 and/or after culture for 1 month.
Results
The method used for the RGD
+
cell–collagen scaffold coupling enabled the following features: high coupling yields and complete washout of excess reagent and by-products with no need for chromatography; spectroscopic quantification of RGD
+
coupling; a spacer arm of 36Å, a length reported as optimal for RGD
+
-peptide presentation and favorable for integrin-receptor clustering and subsequent activation. Isotonic and isometric mechanical parameters, either spontaneous or electrostimulated, exhibited good performance in RGD
+
constructs. Cell number and viability was increased in RGD
+
scaffolds, and we saw good organization of cell contractile apparatus with occurrence of cross-striation.
Conclusions
We report a novel method of engineering a highly effective collagen-cell scaffold based on RGD
+
peptides cross-linked to a clinically approved collagen matrix. The main advantages were cell contractile performance, cardiomyocyte viability and differentiation.
Key Points
We propose a new method for tissue engineering to create an efficient and safe contractile tissue by improving the interaction of contractile cells and their surrounding three-dimensional collagen environment
The approach increases the functionality of collagen templates by covalent binding and optimal presentation of molecules, such as hormones, growth factors, cytokines and adhesive ligand molecules (i.e. arginine–glycine–aspartic acid peptides)
We applied several tools for assessment of myocyte contractility
in vitro
, in three-dimensional cellular architectures under isometric and isotonic conditions
This scaffold might also serve as a platform for improving cellular transplantation in the heart or for engineering a true myocardium equivalent