Three-Dimensional Topography of Synthetic Scaffolds Induces Elastin Synthesis by Human Coronary Artery Smooth Muscle Cells

• Published in: Tissue engineering. Part A 2011-06, Vol.17 (11-12), p.1561-1571
• Main Authors: Lin, Shigang, Sandig, Martin, Mequanint, Kibret
• Format: Article
• Language: English
• Subjects: Adult; Calponin; Cell Adhesion - drug effects; Cell culture; Cell Movement - drug effects; Cell Proliferation - drug effects; Cells; Chemical synthesis; Contractile Proteins - metabolism; coronary artery; Coronary Vessels - cytology; Differentiation; Elastin; Elastin - biosynthesis; Elastin - genetics; Fibronectins - pharmacology; Gene expression; Gene Expression Regulation - drug effects; Humans; Muscle contraction; Myocytes, Smooth Muscle - cytology; Myocytes, Smooth Muscle - drug effects; Myocytes, Smooth Muscle - metabolism; Original Articles; Phenotype; Physiological aspects; Polymerase chain reaction; polyurethane; Polyurethanes - pharmacology; scaffolds; Smooth muscle; Tissue engineering; Tissue Scaffolds - chemistry; Topographical drawing; Topography; Transforming Growth Factor beta1 - pharmacology; Transforming growth factor- beta 1; Transforming growth factors; Western blotting
• ISSN: 1937-3341; 1937-335X
• DOI: 10.1089/ten.tea.2010.0593

Due to the important structural and signaling roles of elastin in vascular stability, engineered human vascular tissues must incorporate elastin. However, despite considerable progress toward engineering of elastin-containing vascular tissues from animal cells, currently engineered vascular tissues using human cells largely lack elastin. In this study, we evaluated the effect of scaffold topography (two dimensional [2D] vs. three dimensional [3D]) on elastogenesis in adult human coronary artery smooth muscle cells (HCASMCs). We report that elastin gene expression by HCASMCs was increased by twofold after 4 days of culture in porous 3D polyurethane scaffolds. Transforming growth factor β1 (TGF-β1) further increased elastin gene expression in 3D cultures but not in 2D cultures. To evaluate if gene expression is translated into elastin synthesis, both 2D and 3D cultures were analyzed using Western blots. We show that only HCASMCs in 3D scaffolds produced elastin, suggesting that scaffold geometry itself is an important cue for elastogenesis. Moreover, TGF-β1 enhanced elastin synthesis in 3D, but had no effect on cells grown on 2D surfaces. TGF-β1, known to induce vascular smooth muscle cells (VSMC) differentiation, upregulated contractile VSMC marker proteins smooth muscle-α-actin and calponin in cells on 2D surfaces. Interestingly, in 3D scaffolds, TGF-β1 failed to upregulate these differentiation marker proteins for at least 7 days, but did so in cells cultured for 14 days, whereas elastin synthesis was not affected. To our knowledge this study is the first to successfully demonstrate that adult human VSMC can produce elastin when seeded on 3D scaffolds and to directly compare the effect of scaffold topography on elastin synthesis. Knowledge about the conditions required to regulate the phenotype of human VSMCs is paramount to engineer elastin-containing autologous human vascular substitutes.