An electro-mechanical bioreactor providing physiological cardiac stimuli

In cardiac tissue engineering it has been widely demonstrated the fundamental role of physical stimuli in improving structural and functional properties of the engineered cardiac constructs. An electro-mechanical bioreactor has been designed and developed to provide physiological uniaxial stretching and electrical stimuli for inducing functional differentiation and promoting morphological and structural maturation of cultured cardiac constructs obtained from stem cell-seeded scaffolds. The bioreactor is composed of: a transparent and sterilizable culture chamber for housing four cell-seeded scaffolds and the culture medium (working volume = 70 ml); a mechanical stimulation system, with a dedicated grasping system, to provide cyclic stretching (strain up to 20%, cycling frequency up to 2 Hz); an electrical stimulation system to provide electrical monophasic square pulses (1-6 V/cm, 0.25-10 ms, 1-5 Hz); a recirculation system for the automated medium change; a control system for data acquisition and mechanical stimulation. Preliminary in-house tests confirmed the suitability and the performances of the bioreactor as regards fittingness of chamber isolation, grasping system, and physical stimulation systems. Cell culture tests are in progress for investigating the influence of stretching and electrical stimuli on development of engineered cardiac constructs. Due to its high versatility, this bioreactor is a multipurpose adaptable system for dynamic culture of cell-seeded scaffolds for tissue engineering research and applications.