Cancer cells tend to grow in an uncontrolled manner, failing to respond to signaling molecules in the same way as healthy cells do. To help study individual cells’ chemical response to these chemicals, researchers at the University of Toronto developed a microfluidic device that can help detect intracellular chemical changes orders of magnitude faster than was previously possible. Digital microfluidic Immunocytochemistry in Single Cells (DISC), as the technique is called, works using a flat microfluidic platform through which small droplets containing chemical signals can be fed to a single living cell. Electrodes below the plate create the electromagnetic fields needed to move the droplets around, mixing as necessary, and moving toward their target.
Once the reaction happens, formaldehyde is added to stop further processes, leaving proteins intact. Fluorescent antibodies are then added that stick to the target proteins that can be detected under a microscope. Multiple cells can be run through the system, with the formaldehyde being added at different times in the process, allowing for data to be gathered throughout the cell’s response period.
From the study abstract in Nature Communications:
DISC was used to probe the phosphorylation states of platelet-derived growth factor receptor (PDGFR) and the downstream signalling protein, Akt, to evaluate concentration- and time-dependent effects of stimulation. The high time resolution of the technique allowed for surprising new observations—for example, a 10 s pulse stimulus of a low concentration of PDGF is sufficient to cause >30% of adherent fibroblasts to commit to Akt activation. With the ability to quantitatively probe signalling events with high time resolution at the single-cell level, we propose that DISC may be an important new technique for a wide range of applications, especially for screening signalling responses of a heterogeneous cell population.
Study in Nature Communications: Digital microfluidic immunocytochemistry in single cells…
Source: University of Toronto…