A microfluidic device for practical label-free CD4(+) T cell counting of HIV-infected subjects

• Published in: Lab on a chip Vol. 7; no. 2; p. 170
• Main Authors: Cheng, Xuanhong, Irimia, Daniel, Dixon, Meredith, Sekine, Kazuhiko, Demirci, Utkan, Zamir, Lee, Tompkins, Ronald G, Rodriguez, William, Toner, Mehmet
• Format: Journal Article
• Language: English
• Published: England 01.01.2007
• Subjects: CD4 Antigens - biosynthesis; CD4 Lymphocyte Count - methods; CD4-Positive T-Lymphocytes - metabolism; CD4-Positive T-Lymphocytes - virology; Cell Adhesion; Chromatography, Affinity; Flow Cytometry - methods; HIV Infections - blood; HIV Seropositivity - blood; Humans; Microfluidic Analytical Techniques - instrumentation; Microfluidic Analytical Techniques - methods; Surface Properties; Time Factors
• ISSN: 1473-0197
• DOI: 10.1039/b612966h

Practical HIV diagnostics are urgently needed in resource-limited settings. While HIV infection can be diagnosed using simple, rapid, lateral flow immunoassays, HIV disease staging and treatment monitoring require accurate counting of a particular white blood cell subset, the CD4(+) T lymphocyte. To address the limitations of current expensive, technically demanding and/or time-consuming approaches, we have developed a simple CD4 counting microfluidic device. This device uses cell affinity chromatography operated under differential shear flow to specifically isolate CD4(+) T lymphocytes with high efficiency directly from 10 microliters of unprocessed, unlabeled whole blood. CD4 counts are obtained under an optical microscope in a rapid, simple and label-free fashion. CD4 counts determined in our device matched measurements by conventional flow cytometry among HIV-positive subjects over a wide range of absolute CD4 counts (R(2) = 0.93). This CD4 counting microdevice can be used for simple, rapid and affordable CD4 counting in point-of-care and resource-limited settings.