Cardiac tissue engineering aims to recreate functional tissue constructs similar to the structure and function of the native myocardium. To date, in vitro tissue constructs lack the architectural complexity of a vascular network and the precise motor unit control of muscle fibers. Here, we present a method to construct engineered multi-strip cardiac muscle that simulates the bundle-like architecture of the native myocardium. Densely packed primary myocytes and cardiac fibroblasts were co-cultured with optogenetic, non-excitable cells. The resulting 3D syncytium triggered contraction upon localized blue light illumination to selectively activate and pace the multi-strip cardiac muscles, similar to the activity of pacemaker cells. Acting on a single load, we demonstrated graded force production through light-modulated multi-strip recruitment. These results demonstrate an in vitro platform of optogenetic, multi-strip cardiac muscles that can be used in a wide variety of applications, such as drug discovery, tissue engineering, and bio-hybrid robotic systems.
ASJC Scopus subject areas
- Biomedical Engineering