Micro-perfusion for cardiac tissue engineering: Development of a bench-top system for the culture of primary cardiac cells

Tissue-engineered constructs have high metabolic requirements during in vitro culture necessitating the development of micro-perfusion systems to maintain high functional performance. In this study, we describe the design, fabrication, and testing of a novel micro-perfusion system to support the culture of primary cardiac cells. Our system consists of a micro-incubator with independent stages for 35-mm tissue culture plates with inflow/outflow manifolds for fluid delivery and aspiration. A peristaltic pump is utilized for fluid delivery and vacuum for fluid aspiration. Oxygen saturation, pH, and temperature are regulated for the media while temperature is regulated within the micro-incubator, fluid reservoir, and oxygenation chamber. Validation of the perfusion system was carried out using primary cardiac myocytes, isolated from 2- to 3-day-old neonatal rat hearts, plated on collagen-coated tissue culture plates. Two million cells/plate were used and the perfusion system was run for 1 h (without the need for a cell culture incubator) while controls were maintained in a standard cell culture incubator. We evaluated the cell viability, cell adhesion, total protein, total RNA, and changes in the expression of SERCA2 and phospholamban using RT-PCR, with N = 6 for each group. We found that there was no significant change in any variable during the 1-h run in the perfusion system. These studies served to demonstrate the compatibility of the perfusion system to support short-term culture of primary cardiac cells.