Controlled delivery of thymosin [beta]4 for tissue engineering and cardiac regenerative medicine

• Published in: Annals of the New York Academy of Sciences Vol. 1269; no. 1; p. 16
• Main Authors: Chiu, Loraine LY, Reis, Lewis A, Radisic, Milica
• Format: Journal Article
• Language: English
• Published: New York Wiley Subscription Services, Inc 01-10-2012
• Subjects: Collagen; Heart attacks; Hydrogels
• ISSN: 0077-8923; 1749-6632
• DOI: 10.1111/j.1749-6632.2012.06718.x

Thymosin [beta]4 (T[beta]4) is a peptide with multiple biological functions. Here, we focus on the role of T[beta]4 in vascularization, and review our studies of the controlled delivery of T[beta]4 through its incorporation in biomaterials. T[beta]4 promotes vascularization through VEGF induction and AcSDKP-induced migration and differentiation of endothelial cells. We developed a collagen-chitosan hydrogel for the controlled release of T[beta]4 over 28 days. In vitro, the T[beta]4-encapsulated hydrogel increased migration of endothelial cells and tube formation from epicardial explants that were cultivated on top of the hydrogel, compared to T[beta]4-free hydrogel and soluble T[beta]4 in the culture medium. In vivo, subcutaneously injected T[beta]4-containing collagen-chitosan hydrogel in rats led to enhanced vascularization compared to T[beta]4-free hydrogel and collagen hydrogel with T[beta]4. Furthermore, the injection of the T[beta]4-encapsulated hydrogel in the infarct region improved angiogenesis, reduced tissue loss, and retained left ventricular wall thickness after myocardial infarction in rats.