384-Channel parallel microfluidic cytometer for rare-cell screening

Abstract

We have constructed a 384-channel parallel microfluidic cytometer (PMC). The multichannel architecture allows 384 unique samples for a cell-based screen to be read out in approximately 6-10 min, about 30-times the speed of a conventional fluorescence-activated cytometer system (FACS). This architecture also allows the signal integration time to be varied over a larger range than is practical in single-channel FACS and is suitable for detection of rare-cells in a high background of negatives. The signal-to-noise advantages have been confirmed by using the system to count rare clonal osteocytes in the most difficult early stages of an expression-cloning screen for the carboxy-terminal parathyroid hormone receptor (CPTHR). This problem requires finding several dozen positive cells in a background of one million negatives. The system is automated around a scanning laser confocal detector and a 96-tip robotic pipettor and can maintain in vitro cultures on-system in 384-well plates. It is therefore directly practical for biology applications using existing high-throughput culture facilities. The PMC system lends itself to high-sample-number cytometry with an unusual capability for time synchronization and rare-cell sensitivity. A limited ability to handle large sample numbers has restricted applications of single-channel FACS in combinatorial cell assays; therefore the PMC could have a significant application in high-throughput screening.

A microflow cytometer exploited for the immunological differentiation of leukocytes

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Vertical hydrodynamic focusing in glass microchannels

“…However, without this change the design presented here appears very suitable for microfluidic cytometry on mammalian cells of about 10-m-diam or larger dimension. 9 FIG. 6.…”

Technology Advancement for Integrative Stem Cell Analyses

“…102,103,[140][141][142][143] The related term ''high-content'' generally describes extracting multiple, different parameters from a set of data, usually images (e.g., protein localization, morphologies, and size). 66,83,87,108,144,145 Neither of these terms, however, describes a comprehensive view of the phenotypic and functional diversity within a population of cells or within the surrounding microenvironment.…”