Formation of toroidal multicellular aggregate of cardiomyocytes

We have proposed a unique multicellular aggregate formation platform that utilizes a maskless gray-scale photolithography. The cellular aggregate formed using this platform has a toroidal-like geometry and includes a micro-pore that facilitates the supply of the oxygen and growth factors and expels waste products. The toroidal multicellular aggregates were easily and non-invasively retrieved from the PDMS platform. A P19.CL6 toroidal multicellular aggregate, which indicates that most of the cells in the aggregate (>; 95%) were still alive after 3 days of culture. By directed assembly of the toroidal multicellular aggregate, the micro-pore can be used as a communicated channel for vascularization and neurogenesis.