Abstract

Node-Pore Sensing: A Versatile, Label-Free Method for Screening Single Cells

Lydia Sohn, Professor, Department of Mechanical Engineering, University of California, Berkeley

Flow cytometry is one of the cornerstones of biomedical research and clinical diagnostics.  With its ability to screen individual cells for multiple protein epitopes simultaneously and subsequently identify sub-populations of cells, flow cytometry has had a profound impact in a broad range of areas including immunology, cancer, and regenerative medicine.  While the current state of-the-art is 18 parameters, flow cytometry is often “practically” limited to 6-10 parameters, as emission spectral overlap is of concern and highly complex analysis to decouple such overlap is needed.  We have developed a rapid, label-free method of screening cells for their phenotypic profile, which we call Node-Pore Sensing (NPS).  NPS involves measuring the modulated current pulse caused by a cell transiting a microchannel that has been segmented by a series of inserted nodes.  When segments between the nodes are functionalized with different antibodies corresponding to distinct cell-surface antigens, cell surface-marker identification can be achieved.  When a “contraction” channel through which cells can squeeze is included between the nodes, mechanical phenotyping is possible.  In this talk, I will demonstrate the versatility of NPS and discuss its potential clinical applications—from phenotyping acute myeloid leukemia patient samples to early breast-cancer detection.