Fig. 2.

Single cell packaging of various human cell lines. (A) Adherent macrophages and (B) brain-derived glioma cells packaged into microdoplets using bioprinting are shown under light microscopy following bioprinting. Arrows show individual cells encapsulated within fluid droplets suspended in droplet generation oil. Approximately 32% of droplets containing single cells. Few droplets contained 2 or more cells (< 6%) and packaging efficiency was similar for macrophages, glioma cells and CD4 + T lymphoctes. (C) Human CD4 + T cells stained with MitroTracker orange encapsulated using microfluidic chips stained with MitoTracker in an overlay of fluorescent signal (Red) on light microscopic images of droplets. MitoTracker staining allowed for the differentiation of encapsulated cells from air bubbles created during microfluidic chip encapsulation which are of a similar size and appearance with light microscopy. (D) Packaging using microfluidic yielded 22% of droplets containing a single cell, and fewer than 5% of droplets containing 2 or more cells at a concentration of 1 × 10⁶ cells/mL input concentration. Error bars represent standard error from 10 replicate experiments.