title: Large unstained cells: a potentially valuable parameter in the assessment of immune activation levels in HIV infection.
abstract: BACKGROUND
  Chronic immune activation is associated with the accelerated progression of HIV to AIDS; however, affordable markers reflecting this have not yet been determined. The percentage of large unstained cells (%LUCs) is a differential count parameter measured by certain routine hematology analyzers and reflects activated lymphocytes and peroxidase-negative cells. We hypothesized that the %LUCs would be increased in HIV infection and would correlate with markers of immune activation [i.e. CD38 expression on CD8+ T cells (%CD38onCD8) and lipopolysaccharide-binding protein (LBP)] and CD4 counts.
  
  
  METHODS
  In this cross-sectional study, 78 HIV-infected, antiretroviral therapy-naïve adults and 52 uninfected controls were recruited. %CD38onCD8 and CD4 counts were determined by flow cytometry, LBP levels were assessed by immunoassay, and the %LUCs was tested on a Siemens ADVIA 2120.
  
  
  RESULTS
  Significant differences were found between the HIV-infected and control groups for %LUCs (95% CI 2.3-2.7 vs. 1.8-2.2, respectively; p = 0.001), as well as for %CD38onCD8, LBP, and CD4 counts. Furthermore, %LUCs correlated directly with %CD38onCD8 and LBP and inversely with CD4 counts.
  
  
  CONCLUSIONS
  The %LUCs was significantly increased in this untreated, asymptomatic, HIV-infected group and correlated with markers of immune activation and CD4 counts. Therefore, the %LUCs may be of value in identifying HIV-infected patients at risk of accelerated disease progression.
authors.affiliation: Division of Haematology, Faculty of Health Sciences, National Health Laboratory Service and Stellenbosch University, Cape Town, South Africa.
authors.forename: Naadira
authors.initials: N
authors.lastname: Vanker
authors.forename: Hayley
authors.initials: H
authors.lastname: Ipp
mesh_terms: D000209:Acute-Phase Proteins / Q000378:metabolism; D000328:Adult; D015415:Biomarkers / Q000097:blood; D044383:Black People; D018791:CD4 Lymphocyte Count; D002352:Carrier Proteins / Q000097:blood / Q000378:metabolism; D048429:Cell Size; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D015658:HIV Infections / Q000276:immunology / Q000473:pathology* / Q000503:physiopathology / Q000821:virology; D015497:HIV-1 / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology* / Q000821:virology; D008297:Male; D008403:Mass Screening; D008562:Membrane Glycoproteins / Q000097:blood / Q000378:metabolism; D012367:RNA, Viral / Q000097:blood / Q000378:metabolism; D013019:South Africa; D019562:Viral Load; D000099231:Lipopolysaccharide-Binding Protein
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D012367:RNA, Viral; D000099231:Lipopolysaccharide-Binding Protein