Mimicking the 3D biology of osteochondral tissue with microfluidic-based solutions: breakthroughs towards boosting drug testing and discovery.

The development of tissue-engineering (TE) solutions for osteochondral (OC) regeneration has been slowed by technical hurdles related to the recapitulation of their complex and hierarchical architecture. OC defects refer to damage of both the articular cartilage and the underlying subchondral bone. To repair an OC tissue defect, the complexity of the bone and cartilage must be considered. To help achieve this, microfluidics is converging with TE approaches to provide new treatment possibilities. Microfluidics uses precise micrometer-to-millimeter-scale fluid flows to achieve high-resolution and spatial and/or temporal control of the cell microenvironment, providing powerful tools for cell culturing. Herein, we overview the progress of microfluidics for developing 3D in vitro models of OC tissue, with a focus on cancer bone metastasis.