Long-term culture of embryonic rat cardiomyocytes on an organosilane surface in a serum-free medium.

Potential applications of engineered, functional, cardiac muscle extends from basic research through drug discovery to engineering heart tissue for transplantation. One of the central questions in cardiac tissue engineering is to understand and control the complex interactions between the cardiac muscle cells and their environment. Recent progress in chemistry, material science, and cell biology have made possible the control of the extracellular environment (soluble factors and also cell-substrate signaling) in in vitro systems. In this study we report on the development of a defined system (artificial surface, serum-free medium combination, consistent cell preparation), which promotes the differentiation and long-term survival of rat embryonic cardiomyocytes. Cardiac muscle cells plated on a N-1 (3-(trimethoxysilyl) propyl) diethylenetriamine (DETA) surface in serum-free medium survived for more than 8 weeks in vitro and maintained their contractile and electrophysiological properties. Our methods are also compatible with advanced cell patterning techniques such as microcontact printing and photolithography which now could enable systematic spacial modifications to create growth substrates for the study of the role of contact signaling in cardiac myocyte development and physiology. It also provides a test-bed for the long-term evaluation of soluble compounds such as toxins and drug candidates in a defined system.