title: The ARTμS: a novel microfluidic CD4+ T-cell enumeration system for monitoring antiretroviral therapy in HIV patients.
abstract: We report on a novel and cost-effective microfluidic platform that integrates immunomagnetic separation and cell enumeration via DNA-induced bead aggregation. Using a two-stage immunocapture microdevice, 10 μL of whole blood was processed to isolate CD4+ T-cells. The first stage involved the immuno-subtraction of monocytes by anti-CD14 magnetic beads, followed by CD4+ T-cell capture with anti-CD4 magnetic beads. The super hydrophilic surface generated during polydimethylsiloxane (PDMS) plasma treatment allowed for accurate metering of the CD4+ T-cell lysate, which then interacted with silica-coated magnetic beads under chaotropic conditions to form aggregates. Images of the resulting aggregates were captured and processed to reveal the mass of DNA, which was used to back-calculate the CD4+ T-cell number. Studies with clinical samples revealed that the analysis of blood within 24 hours of phlebotomy yielded the best results. Under these conditions, an accurate cell count was achieved (R(2) = 0.98) when compared to cell enumeration via flow cytometry, and over a functional dynamic range from 106-2337 cells per μL.
authors.affiliation: Department of Chemistry, University of Virginia, McCormick Road, P. O. Box 400319, Charlottesville, Virginia 22904, USA. landers@virginia.edu and Center For Microsystems For The Life Sciences, University of Virginia, Charlottesville, Virginia 22904, USA.
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Chemistry, University of Virginia, McCormick Road, P. O. Box 400319, Charlottesville, Virginia 22904, USA. landers@virginia.edu.
authors.forename: Alexis
authors.initials: A
authors.lastname: Chernish
authors.affiliation: Department of Chemistry, University of Virginia, McCormick Road, P. O. Box 400319, Charlottesville, Virginia 22904, USA. landers@virginia.edu and Center For Microsystems For The Life Sciences, University of Virginia, Charlottesville, Virginia 22904, USA.
authors.forename: Jacquelyn A
authors.initials: JA
authors.lastname: DuVall
authors.affiliation: Department of Chemistry, University of Virginia, McCormick Road, P. O. Box 400319, Charlottesville, Virginia 22904, USA. landers@virginia.edu and Center For Microsystems For The Life Sciences, University of Virginia, Charlottesville, Virginia 22904, USA.
authors.forename: Yiwen
authors.initials: Y
authors.lastname: Ouyang
authors.affiliation: Department of Chemistry, University of Virginia, McCormick Road, P. O. Box 400319, Charlottesville, Virginia 22904, USA. landers@virginia.edu and Center For Microsystems For The Life Sciences, University of Virginia, Charlottesville, Virginia 22904, USA.
authors.forename: Jingyi
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Chemical Engineering, University of Virginia, Charlottesville, VA 22904, USA.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Qian
authors.affiliation: Department of Chemistry, University of Virginia, McCormick Road, P. O. Box 400319, Charlottesville, Virginia 22904, USA. landers@virginia.edu and Department of Pathology, University of Virginia Health Science Center, Charlottesville, Virginia 22908, USA.
authors.forename: Lindsay A L
authors.initials: LA
authors.lastname: Bazydlo
authors.affiliation: Department of Pathology, University of Virginia Health Science Center, Charlottesville, Virginia 22908, USA.
authors.forename: Doris M
authors.initials: DM
authors.lastname: Haverstick
authors.affiliation: Department of Chemistry, University of Virginia, McCormick Road, P. O. Box 400319, Charlottesville, Virginia 22904, USA. landers@virginia.edu and Department of Pathology, University of Virginia Health Science Center, Charlottesville, Virginia 22908, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Landers
mesh_terms: D044966:Anti-Retroviral Agents / Q000008:administration & dosage*; D018791:CD4 Lymphocyte Count / Q000295:instrumentation / Q000379:methods; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology; D006801:Humans; D008297:Male; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods
chemical_list: D044966:Anti-Retroviral Agents