Tissue-engineered 3-dimensional microenvironment enhances the direct reprogramming of fibroblasts into cardiomyocytes by microRNAs

Developers

Yanzhen Li, Sophie Dal-Pra, Maria Mirotsou, Nenad Bursac, Victor J. Dzau.

Description of the technology

The technology has been created in the frameworks of the improvement of reprogramming process of neonatal cardiac fibroblasts into cells of myocardium. Recently the authors of this technology found that a combination of microRNAs, miR combo, can directly reprogram cardiac fibroblasts into functional cardiomyocytes in vitro and in vivo. Reprogramming of cardiac fibroblasts by miR combo in vivo is associated with improved cardiac function following myocardial infarction. However, the efficiency of direct reprogramming in vitro is relatively modest and new strategies beyond the traditional two-dimensional (2D) culture should be identified to improve reprogramming process.

It was found in process of developing this technology that a tissue-engineered three-dimensional (3D) hydrogel environment enhanced miR combo reprogramming of neonatal cardiac and tail-tip fibroblasts. The limitations of conventional 2D cultures are that they do not faithfully reproduce the structure and composition of extracellular matrix, concentrations of soluble factors, mechanical signals, and cell-cell communication present in native tissues. Since these signaling key features play critical roles in regulating cell differentiation and function, it is expectable result that 3D culture systems have promoted maturation of primary or stem cell-derived cardiomyocytes. The process was also associated with significantly increased matrix metalloproteinases (MMPs) expression in 3D vs. 2D cultured cells, herewith pharmacological inhibition of MMPs blocked the effect of the 3D culture on enhanced miR combo mediated reprogramming. Thus, 3D tissue-engineered environment can enhance the direct reprogramming of fibroblasts to cardiomyocytes via a MMP-dependent mechanism.

Practical application

This technology is important first step towards the future use of tissue-engineered strategies to aid fibroblast targeted therapies for regeneration of infarcted heart tissues. These findings have been obtained for cardiomyocytes, however the principles of this work (in particular, replacement of 2D cell cultures by 3D ones) can be useful for reprogramming strategies aimed at other tissues and lineages.

Laboratories

• Department of Biomedical Engineering, Duke University, Durham (USA)
• Mandel Center for Hypertension Research and Duke Cardiovascular Research Center, Department of Medicine, Duke University Medical Center, Durham, (USA)

Links

Publications

• Li, Y. «Tissue-engineered 3-dimensional (3D) microenvironment enhances the direct reprogramming of fibroblasts into cardiomyocytes by microRNAs." 6 Sci Rep. (2016): 38815.
• Bian, W. et al. «Robust T-tubulation and maturation of cardiomyocytes using tissue-engineered epicardial mimetics." 35 Biomaterials, (2014): 3819–3828.
• Liau, B., Zhang, D. & Bursac, N. Functional cardiac tissue engineering. Regenerative medicine, (2012): 187–206.