Node-pore sensing: A label-free platform to screen single cells for their phenotypic profile

Abstract:

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 measures the modulated current pulse caused by a cell transiting a microchannel that has been segmented by a series of inserted nodes. When the segments between the nodes are functionalized with different antibodies corresponding to distinct cell-surface antigens, cells whose antigens interact specifically with the functionalized antibodies in a particular segment will travel more slowly through that section of the channel than that through the isotype-control. Surface-marker identification is accomplished by comparing transit times within the modulated pulse. I will show the versatility of NPS and discuss how we are using this method in a pilot clinical study to phenotype acute myeloid leukemia patient samples. Furthermore, I will discuss the next-generation NPS, which involves using analysis techniques borrowed from radar and telecommunications theory.