A mother-machine microfluidic device for non-adherent mammalian cells reveals the population growth strategies

We develop a mother machine-like microfluidic device specifically designed to track the proliferation of T-cells via live-cell microscopy. Although numerous microfluidic setups have been developed to study cell proliferation at the single-cell level, most of them are optimized for use on adherent cells. Here, we present a device to track the proliferation of suspension cells, featuring an array of microchannels that trap cells, easing their monitoring while allowing for controlled growth conditions. Each microchannel, whose geometry has been optimized through computational fluid dynamics simulations, allows a single cell to enter and proliferate while maintaining a continuous flow of nutrients, ensuring long-term monitoring over multiple generations. We show the advantages of this system in characterizing the proliferation of human leukemia T-cells. In particular, we follow the growth and division over multiple generations, finding that cells exhibit a slightly asymmetric volume division where deviations in the size are compensated by a size-like division strategy. Overall, our device design can be easily adapted and used to study different cell types and sizes while maintaining the same high trapping efficiency.