DROPLET MICROFLUIDIC APPROACHES FOR SINGLE-CELL PROTEOLYTIC FUNCTIONAL ASSAY

Abstract

Every cell has its distinct phenotype, behavior and function. However, conventional biological analytical assays, such as western blot and enzyme-linked immunosorbent assay, adopt ensemble measurements to extract the average information from non-homogeneous cell populations without taking into account the critical details of individual cells. Such simplistic methods could generate misleading results from highly heterogeneous cells, like cancer and immune cells. In order to accurately and effectively study functional heterogeneity of single cancer and immune cells, we developed a series of microfluidic droplet platforms. We first developed a novel and label-free droplet system to enhance single-cell encapsulation efficiency by incorporating jetting and size-based sorting. Next, we applied the droplet microfluidics to study single-cell matrix metalloproteinase activity of various breast cancer cell lines and patient-derived circulating tumor cells. Lastly, we developed a new droplet microfluidic system to study matrix metalloproteinase of single leukocytes with solving the pre-encapsulation contamination issue.