Abstract

Probing Cellular Heterogeneity in Cytokine-secreting Cells using High-throughput Droplet-based Microfluidics

Jurjen Tel, Postdoctoral Fellow, Radboud University Nijmegen Medical Centre

Our current understanding of cellular responses to external stimuli has generally been obtained using bulk assays on populations of cells. These studies hide the response of individual cells, which do not necessarily reflect the bulk behaviour. This lack of insight into cellular behavior at the single-cell level is particularly important in immunology. Here, we present a platform to detect cytokine (IL-2, IFN-?, TNF-a) secretion of single, activated T-cells in droplets over time. We use a novel droplet-based microfluidic approach to encapsulate cells in monodisperse agarose droplets together with functionalized cytokine-capture beads for subsequent binding and detection of secreted cytokines from single cells. This method allows high-throughput detection of cellular heterogeneity and maps subsets within cell populations with specific functions. The results from this study validate droplet microfluidics as a strong and innovative tool to study and manipulate single-cell behaviour. The impact of rapid expansion of high-throughput single-cell analysis is evident in its great potential for numerous applications, including drug discovery, diagnostics, cancer research, regenerative medicine, system and synthetic biology, and many others.