Microfluidic device simulates human tissue and offers an alternative to animal testing

Cells in the body operate within a rich environment, receiving chemical signals from surrounding cells and the extracellular matrix. When using suspended, 3D cell cultures to study these tissues, researchers can apply both mechanical stimulation and replicate the complex, spatially varied, non-planar structures found in vivo. STEAM (Suspended Tissue Engineering with Assemblable Microfluidics) is a cost-effective, modular platform that can create both planar and non-planar tissues using fluidic patterning to form multiregional structures.

In this study, the STEAM dome platform was further investigated, with a focus on developing a mathematical model that explains the requirements for two-region patterning in non-planar structures. The research applied the STEAM platform to develop bladder models, representing a sphere-like organ with concentric layers and a central lumen that expand and contract during filling and emptying.

The planar bladder smooth muscle tissue patch showed inherent tension, which increased with further straining, leading to muscle cell alignment along the stretch axis. The non-planar STEAM platform was used to create a bilayered bladder wall model using human urothelial cells and primary bladder smooth muscle cells. This approach provides an accessible and low-cost alternative to generate complex, spatially and geometrically intricate suspended tissues.