Article

Naturally derived myocardial matrix as an injectable scaffold for cardiac tissue engineering. Biomaterials

Department of Bioengineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0412, USA.
Biomaterials (Impact Factor: 8.56). 08/2009; 30(29):5409-16. DOI: 10.1016/j.biomaterials.2009.06.045
Source: PubMed

ABSTRACT

Myocardial tissue lacks the ability to significantly regenerate itself following a myocardial infarction, thus tissue engineering strategies are required for repair. Several injectable materials have been examined for cardiac tissue engineering; however, none have been designed specifically to mimic the myocardium. The goal of this study was to investigate the in vitro properties and in vivo potential of an injectable myocardial matrix designed to mimic the natural myocardial extracellular environment. Porcine myocardial tissue was decellularized and processed to form a myocardial matrix with the ability to gel in vitro at 37 degrees C and in vivo upon injection into rat myocardium. The resulting myocardial matrix maintained a complex composition, including glycosaminoglycan content, and was able to self-assemble to form a nanofibrous structure. Endothelial cells and smooth muscle cells were shown to migrate towards the myocardial matrix both in vitro and in vivo, with a significant increase in arteriole formation at 11 days post-injection. The matrix was also successfully pushed through a clinically used catheter, demonstrating its potential for minimally invasive therapy. Thus, we have demonstrated the initial feasibility and potential of a naturally derived myocardial matrix as an injectable scaffold for cardiac tissue engineering.

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Available from: Karen L Christman, Dec 31, 2013
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    • "Only patient age was provided for the six patients (p1-6) and is as follows: p1-43, p2-52, p3-63, p4-69, p5-63, and p6-34. The methods for decellularizing human myocardial tissue have been previously reported [4], and were based on methods developed for decellularizing porcine myocardium [6]. In brief, human cardiac tissue was collected from 6 different patients. "
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    • "Left ventricular tissue was separated from the rest of the heart and utilized for matrix collection. The left ventricular tissue was decellularized and prepared as previously described [43] [44]. "
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    • "Preparation of ECM-only hydrogels ECM hydrogels were prepared using various concentrations of TG (0, 1.2, 12 and 120 lg ml À1 ). Decellularized ECM solution was neutralized and diluted to 6 mg ml À1 [16] before adding TG, vortexed briefly and then pipetted into 15 Â 15 Â 5 mm Tissue-Tek cryomolds (Ted Pella, Inc.). Samples were incubated at 37 °C for $30 min. "
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