The study of cellular heterogeneity and analysis of rare cell types has the potential to deliver great insights into a number of disease states, particularly in conditions associated with ageing and cancer. However, the technical challenges associated with such small systems mean that a whole new tool kit is required to extract meaningful, quantitative data. As a result, we have developed a suite of optically-manipulated Smart Droplet Microtools (SDMs)1 capable of sampling from or delivering to the membrane of an individual cell amongst a population, in a manner that is non-destructive, temporally resolved and repeatable. We have demonstrated the collection of inner-leaflet proteins and their deposition onto supported bilayers for later study,2 and have used related technologies to deliver known quantities of plasmid to single cells for quantitative dose-response transfection studies.
This means that for the first time we are capable of studying the responses of individual cells to stimuli in a way that lays bare their heterogeneity. When coupled with the single-molecule-sensitivity of the group’s microfluidic antibody capture chip technology,3 this will enable the quantitative readout of cellular function throughout any given cell’s life cycle.