Microfluidic cell-phoresis enabling high-throughput analysis of red blood cell deformability and biophysical screening of antimalarial drugs

Abstract

Changes in red blood cell (RBC) deformability are associated with the pathology of many diseases and could potentially be used to evaluate disease status and treatment efficacy. We developed a simple, sensitive, and multiplexed RBC deformability assay based on the spatial dispersion of single cells in structured microchannels. This mechanism is analogous to gel electrophoresis, but instead of transporting molecules through nano-structured material to measure their length, RBCs are transported through micro-structured material to measure their deformability. After transport, the spatial distribution of cells provides a readout similar to intensity bands in gel electrophoresis, enabling simultaneous measurement on multiple samples. We used this approach to study the biophysical signatures of falciparum malaria, for which we demonstrate label-free and calibration-free detection of ring-stage infection, as well as in vitro assessment of antimalarial drug efficacy. We show that clinical antimalarial drugs universally reduce the deformability of RBCs infected by Plasmodium falciparum and that recently discovered PfATP4 inhibitors, known to induce host-mediated parasite clearance, display a distinct biophysical signature. Our process captures key advantages from gel electrophoresis, including image-based readout and multiplexing, to provide a functional screen for new antimalarials and adjunctive agents.

Deformability based sorting of stored red blood cells reveals donor-dependent aging curves

“…Traditional single cell manipulation, including micropipette aspiration 33,34 , optical tweezers 35 , and atomic force microscopy 36 , involve technically challenging experiments that require skilled personnel and highly specialized equipment. Microfluidic approaches for deformation based RBC deformability analysis include the measurement of capillary obstruction 37 , wedging in tapered constrictions 38,39 , transiting time through constrictions [40][41][42][43] , and transiting pressure through constrictions 17,44,45 . While these approaches greatly simplified RBC deformability analysis, the throughput of these processes are still relatively limited.…”

High-throughput physical phenotyping of cell differentiation

“…However, both methods are time and labor intensive (tens of cells per hour), posing challenges for examining large populations of cells to either obtain statistically valid conclusions or identify rare sub-populations. Recent advances in micro-/nano-fabrication technologies have opened up a range of new mechanophenotyping technologies that can measure deformations of tens to hundreds of cells per second [11][12][13][14][15][16][17][18][19] . We recently reported a technology, called deformability cytometry, in which a cross-slot microfluidic channel is employed to generate a hydrodynamic extension zone where individual cells are exposed to uniform hydrodynamic stress and deformed 20 .…”

Structural and functional studies of erythrocyte membrane-skeleton by single-cell and single-molecule techniques

“…4(d)). 61 Based on application of di®erent micro°uidic channels, they all suggested that erythrocyte deformability decreased signi¯cantly under various abnormal conditions, such as malaria-infection, 62,63 blood storage lesion, 64,65 diabetes 66,67 and sickle cell disease. 68,69 Compared with the optical tweezers and the micropipette aspiration, the micro°uidic channels provided a unique opportunity to investigate erythrocyte deformability in a rapid, highthroughput and relatively easy-to-use method at single-cell level.…”