Size regulation of chondrocyte spheroids using a PDMS-based cell culture chip

Cartilage self-repair is limited due to a lack of blood supply and the low mitosis rate of chondrocytes. A tissue engineering approach using cells and biomaterials has the potential to treat cartilage injury. Threedimensional cellular aggregates are an excellent model for mimicking condensation and chondrogenic differentiation in vitro. We developed a technique for constructing spheroids utilizing a polydimethylsiloxane (PDMS)-based culture chip. The objective of this study is to determine how the initial cell density on a culture chip affects the chondrogenic ATDC5 cell differentiation. We demonstrate how culture chips having arrays of multicavities are able to generate high numbers of uniform spheroids rapidly and simultaneously with narrow size distribution. Spheroids are collected easily and noninvasively. Higher cell seeding density on the culture chip enhances chondrogenic cell differentiation. These results suggest the usefulness of this chip in engineering 3D cellular constructs with high functionality for tissue engineering.