Proper function of the aortic valve is critically important for efficient cardiac performance. Calcific aortic valve disease (CAVD) is characterized by progressive stenosis (narrowing) of the valve opening and the formation of thick calcified deposits on the surfaces of the valve leaflets. While up to 10% of Americans over 65 are affected with AVD, a nearly equal number of Americans are born with congenital malformations of the aortic valve that result in premature degeneration. Clinical trials using drugs and biomarkers found effective in atherosclerosis have been largely unsuccessful in diagnosing, predicting, or halting AVD progression. Both atherosclerosis and AVD present initially with an inflamed endothelium, but the molecular and cellular mechanisms by which endothelial cells regulate interstitial cell phenotype and subsequent matrix mineralization at late stages are largely unknown. Two mechanisms of calcification have been hypothesized (dystrophic and osteogenic), but how these modes participate after the onset of matrix mineralization (when CAVD is almost always discovered) is unknown. Recent evidence suggests that valve phenotypes and calcium deposition are modulated by cyclic mechanical strain, but how strain affects cells in later stage calcification environments is unknown. The vast majority of research efforts to understand this disease process utilize very long-term mouse models (>10 months) that are difficult to control the local valve microenvironment, while current in vitro culture systems lack physiological cell interactions and 3D biological matrix components. A more rapid, physiological culture platform is therefore essential to identifying mechanisms of mid and late-term CAVD. In this application we will implement a novel 3D in vitro culture platform that incorporates collagen matrix and tunable synthetic hydroxyapatite crystal nanoparticles to mimic the natural calcified aortic valve environment. With this system we will test how aortic valve endothelial cells (VEC) and interstitial cells (VIC) respond to early and lat calcified tissue environments. Our application has two Aims.
The first aim will explore the effects of hydroxyapatite mineral crystallinity and burden on VEC and VIC phenotype, both individually and in co-culture.
The second aim will assess how these relationships are modulated by different patterns of cyclic biaxial strain in 3D culture. In both aims, we will focus on early differentiation behavior and late term matrix remodeling. The results of this application will validate a novel 3D in vitro strategy to rapidly identify novel molecular and cellular signatures o disease pathogenesis specific to valve cells, which will significantly inform future therapeutic strategies to prevent valve mineralization at each phase of the disease process.

Public Health Relevance

This application will establish a novel 3D cell culture platform including native heart valve cells and hydroxyapatite crystal components for accelerating the discovery and evaluation of novel cellular and molecular processes in calcific aortic valve disease (CAVD). We will investigate how matrix mineralization and cyclic biaxial strain modulate valve endothelial-interstitial cell phenotypes. These results will help validate an experimental approach to identify and screen anti-calcific agents for clinically relevant later stages of CAVD.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Exploratory/Developmental Grants (R21)
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Biomaterials and Biointerfaces Study Section (BMBI)
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Evans, Frank
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Cornell University
Engineering (All Types)
Schools of Engineering
United States
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Richards, Jennifer M; Kunitake, Jennie A M R; Hunt, Heather B et al. (2018) Crystallinity of hydroxyapatite drives myofibroblastic activation and calcification in aortic valves. Acta Biomater 71:24-36
Kang, Laura Hockaday; Armstrong, Patrick A; Lee, Lauren Julia et al. (2017) Optimizing Photo-Encapsulation Viability of Heart Valve Cell Types in 3D Printable Composite Hydrogels. Ann Biomed Eng 45:360-377
Sung, Derek C; Bowen, Caitlin J; Vaidya, Kiran A et al. (2016) Cadherin-11 Overexpression Induces Extracellular Matrix Remodeling and Calcification in Mature Aortic Valves. Arterioscler Thromb Vasc Biol 36:1627-37
Farrar, Emily J; Pramil, Varsha; Richards, Jennifer M et al. (2016) Valve interstitial cell tensional homeostasis directs calcification and extracellular matrix remodeling processes via RhoA signaling. Biomaterials 105:25-37
Duan, Bin; Yin, Ziying; Hockaday Kang, Laura et al. (2016) Active tissue stiffness modulation controls valve interstitial cell phenotype and osteogenic potential in 3D culture. Acta Biomater 36:42-54
Gould, Russell A; Yalcin, Huseyin C; MacKay, Joanna L et al. (2016) Cyclic Mechanical Loading Is Essential for Rac1-Mediated Elongation and Remodeling of the Embryonic Mitral Valve. Curr Biol 26:27-37
Bowen, Caitlin J; Zhou, Jingjing; Sung, Derek C et al. (2015) Cadherin-11 coordinates cellular migration and extracellular matrix remodeling during aortic valve maturation. Dev Biol 407:145-57
Duan, Bin; Hockaday, Laura A; Das, Shoshana et al. (2015) Comparison of Mesenchymal Stem Cell Source Differentiation Toward Human Pediatric Aortic Valve Interstitial Cells within 3D Engineered Matrices. Tissue Eng Part C Methods 21:795-807
Farrar, Emily J; Huntley, Geoffrey D; Butcher, Jonathan (2015) Endothelial-derived oxidative stress drives myofibroblastic activation and calcification of the aortic valve. PLoS One 10:e0123257
Cheung, Daniel Y; Duan, Bin; Butcher, Jonathan T (2015) Current progress in tissue engineering of heart valves: multiscale problems, multiscale solutions. Expert Opin Biol Ther 15:1155-72

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