Bingzhao Xia, Joan Li, Zachary Lim, Justin Cooper-White*


Australian Institute for Bioengineering and Nanotechnology

University of Queensland

Brisbane, Queensland, Australia


In spite of improved clinical approaches to recovery from an acute myocardial infarction (a heart attack), heart failure remains one of the leading causes of death worldwide. Direct reprogramming, as a way in which to convert human fibroblasts into functional cardiomyocytes, has been intensively explored as a potential treatment for ischemic heart disease in recent years. However, its therapeutic utility is severely limited by the current approaches that rely on the use of viral delivery systems. Polyethylenimine (PEI), as a nonviral gene delivery system, has been successfully demonstrated to efficiently deliver small plasmids into various cell types. Although this promising approach is widely pursued, dramatic decreases in transfection efficiency were observed with plasmids of 10 Kb or more when we used them with primary human cardiac fibroblasts. Many factors can affect the transfection efficiency, such as salts, volume, and incubation time. In this work, we systematically examine the effects of these environmental factors upon the transfection efficiency, by measuring the size of carrier-DNA complexes. It was found the size of the PEI/DNA complexes did not have direct effect on the process of endocytosis, but it does have a significant effect upon the resultant gene expression. By optimizing these parameters, we have developed an efficient and reproducible method to perform direct reprogramming of cardiac fibroblasts into cardiomyocytes using a non-viral approach. Conclusions drawn from this work also provide a comprehensive set of guidelines to optimising large plasmid transfection for other primary cells.


Biographic Details

Name: Bingzhao Xia

Title: Microfluidics Bioengineer

Affiliation, Country: AIBN, University of Queensland, Australia

Phone: +61 (0)7 334 64287  E-mail:

Research interests: tissue engineering