posted on 2017-04-13, 00:00authored byRocio J. Jimenez-Valdes, Roberto Rodriguez-Moncayo, Diana F. Cedillo-Alcantar, Jose L. Garcia-Cordero
New
tools that facilitate the study of cell-to-cell variability
could help uncover novel cellular regulation mechanisms. We present
an integrated microfluidic platform to analyze a large number of single
cells in parallel. To isolate and analyze thousands of individual
cells in multiplexed conditions, our platform incorporates arrays
of microwells (7 pL each) in a multilayered microfluidic device. The
device allows the simultaneous loading of cells into 16 separate chambers,
each containing 4640 microwells, for a total of 74 240 wells
per device. We characterized different parameters important for the
operation of the microfluidic device including flow rate, solution
exchange rate in a microchamber, shear stress, and time to fill up
a single microwell with molecules of different molecular weight. In
general, after ∼7.5 min of cell loading our device has an 80%
microwell occupancy with 1–4 cells, of which 36% of wells contained
a single cell. To test the functionality of our device, we carried
out a cell viability assay with adherent and nonadherent cells. We
also studied the production of neutrophil extracellular traps (NETs)
from single neutrophils isolated from peripheral blood, observing
the existence of temporal heterogeneity in NETs production, perhaps
having implications in the type of the neutrophil response to an infection
or inflammation. We foresee our platform will have a variety of applications
in drug discovery and cellular biology by facilitating the characterization
of phenotypic differences in a monoclonal cell population.