title: Enumeration of CD4+ T-cells using a portable microchip count platform in Tanzanian HIV-infected patients.
abstract: BACKGROUND
  CD4(+) T-lymphocyte count (CD4 count) is a standard method used to monitor HIV-infected patients during anti-retroviral therapy (ART). The World Health Organization (WHO) has pointed out or recommended that a handheld, point-of-care, reliable, and affordable CD4 count platform is urgently needed in resource-scarce settings.
  
  
  METHODS
  HIV-infected patient blood samples were tested at the point-of-care using a portable and label-free microchip CD4 count platform that we have developed. A total of 130 HIV-infected patient samples were collected that included 16 de-identified left over blood samples from Brigham and Women's Hospital (BWH), and 114 left over samples from Muhimbili University of Health and Allied Sciences (MUHAS) enrolled in the HIV and AIDS care and treatment centers in the City of Dar es Salaam, Tanzania. The two data groups from BWH and MUHAS were analyzed and compared to the commonly accepted CD4 count reference method (FACSCalibur system).
  
  
  RESULTS
  The portable, battery operated and microscope-free microchip platform developed in our laboratory (BWH) showed significant correlation in CD4 counts compared with FACSCalibur system both at BWH (r = 0.94, p<0.01) and MUHAS (r = 0.49, p<0.01), which was supported by the Bland-Altman methods comparison analysis. The device rapidly produced CD4 count within 10 minutes using an in-house developed automated cell counting program.
  
  
  CONCLUSIONS
  We obtained CD4 counts of HIV-infected patients using a portable platform which is an inexpensive (<$1 material cost) and disposable microchip that uses whole blood sample (<10 µl) without any pre-processing. The system operates without the need for antibody-based fluorescent labeling and expensive fluorescent illumination and microscope setup. This portable CD4 count platform displays agreement with the FACSCalibur results and has the potential to expand access to HIV and AIDS monitoring using fingerprick volume of whole blood and helping people who suffer from HIV and AIDS in resource-limited settings.
authors.affiliation: Demirci Bio-Acoustic MEMS Laboratory, Center for Biomedical Engineering, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: SangJun
authors.initials: S
authors.lastname: Moon
authors.forename: Umut Atakan
authors.initials: UA
authors.lastname: Gurkan
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Blander
authors.forename: Wafaie W
authors.initials: WW
authors.lastname: Fawzi
authors.forename: Said
authors.initials: S
authors.lastname: Aboud
authors.forename: Ferdinand
authors.initials: F
authors.lastname: Mugusi
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Kuritzkes
authors.forename: Utkan
authors.initials: U
authors.lastname: Demirci
mesh_terms: D000293:Adolescent; D000328:Adult; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D015658:HIV Infections / Q000097:blood / Q000276:immunology*; D006801:Humans; D056656:Lab-On-A-Chip Devices; D008297:Male; D046208:Microchip Analytical Procedures / Q000379:methods*; D019095:Point-of-Care Systems; D013636:Tanzania; D014944:World Health Organization; D055815:Young Adult