title: Automated leukocyte processing by microfluidic deterministic lateral displacement.
abstract: We previously developed a Deterministic Lateral Displacement (DLD) microfluidic method in silicon to separate cells of various sizes from blood (Davis et al., Proc Natl Acad Sci 2006;103:14779-14784; Huang et al., Science 2004;304:987-990). Here, we present the reduction-to-practice of this technology with a commercially produced, high precision plastic microfluidic chip-based device designed for automated preparation of human leukocytes (white blood cells; WBCs) for flow cytometry, without centrifugation or manual handling of samples. After a human blood sample was incubated with fluorochrome-conjugated monoclonal antibodies (mAbs), the mixture was input to a DLD microfluidic chip (microchip) where it was driven through a micropost array designed to deflect WBCs via DLD on the basis of cell size from the Input flow stream into a buffer stream, thus separating WBCs and any larger cells from smaller cells and particles and washing them simultaneously. We developed a microfluidic cell processing protocol that recovered 88% (average) of input WBCs and removed 99.985% (average) of Input erythrocytes (red blood cells) and >99% of unbound mAb in 18 min (average). Flow cytometric evaluation of the microchip Product, with no further processing, lysis or centrifugation, revealed excellent forward and side light scattering and fluorescence characteristics of immunolabeled WBCs. These results indicate that cost-effective plastic DLD microchips can speed and automate leukocyte processing for high quality flow cytometry analysis, and suggest their utility for multiple other research and clinical applications involving enrichment or depletion of common or rare cell types from blood or tissue samples. © 2016 International Society for Advancement of Cytometry.
authors.affiliation: Departments of Pediatrics and Physiology, Center for Stem Cell Biology and Regenerative Medicine and Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, 21201.
authors.forename: Curt I
authors.initials: CI
authors.lastname: Civin
authors.affiliation: GPB Scientific LLC, Richmond, Virginia, 23219.
authors.forename: Tony
authors.initials: T
authors.lastname: Ward
authors.affiliation: GPB Scientific LLC, Richmond, Virginia, 23219.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Skelley
authors.affiliation: GPB Scientific LLC, Richmond, Virginia, 23219.
authors.forename: Khushroo
authors.initials: K
authors.lastname: Gandhi
authors.affiliation: GPB Scientific LLC, Richmond, Virginia, 23219.
authors.forename: Zendra
authors.initials: Z
authors.lastname: Peilun Lee
authors.affiliation: GPB Scientific LLC, Richmond, Virginia, 23219.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Dosier
authors.affiliation: Department of Electrical Engineering, Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544.
authors.forename: Joseph L
authors.initials: JL
authors.lastname: D'Silva
authors.affiliation: Department of Electrical Engineering, Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Departments of Pediatrics and Physiology, Center for Stem Cell Biology and Regenerative Medicine and Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, 21201.
authors.forename: MinJung
authors.initials: M
authors.lastname: Kim
authors.affiliation: Departments of Pediatrics and Physiology, Center for Stem Cell Biology and Regenerative Medicine and Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, 21201.
authors.forename: James
authors.initials: J
authors.lastname: Moynihan
authors.affiliation: Departments of Pediatrics and Physiology, Center for Stem Cell Biology and Regenerative Medicine and Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, 21201.
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Chen
authors.affiliation: GPB Scientific LLC, Richmond, Virginia, 23219.
authors.forename: Lee
authors.initials: L
authors.lastname: Aurich
authors.affiliation: Beckman Coulter Life Sciences, Miami, Florida, 33196.
authors.forename: Sergei
authors.initials: S
authors.lastname: Gulnik
authors.affiliation: Beckman Coulter Life Sciences, Miami, Florida, 33196.
authors.forename: George C
authors.initials: GC
authors.lastname: Brittain
authors.affiliation: Desatoya LLC, Reno, Nevada, 89507.
authors.forename: Diether J
authors.initials: DJ
authors.lastname: Recktenwald
authors.affiliation: Department of Physics, Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Austin
authors.affiliation: Department of Electrical Engineering, Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey, 08544.
authors.forename: James C
authors.initials: JC
authors.lastname: Sturm
mesh_terms: D002469:Cell Separation / Q000379:methods; D005434:Flow Cytometry / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D056656:Lab-On-A-Chip Devices; D007962:Leukocytes
keywords: blood; cell processing; cell sorting; deterministic lateral displacement; leukocytes; microfluidic; red blood cells; sample preparation; white blood cells