title: [Effect of duration and temperature of sample preservation on the result of peripheral blood CD4+ and CD8+ T lymphocyte count in HIV/AIDS patients].
abstract: BACKGROUND
  By analyzing the CD4+ and CD8+ T lymphocyte count of whole blood from HIV/AIDS patients, which were stored at different temperatures for various durations, the authors studied the ideal preserving condition for whole blood and processed, in a purpose of guaranteeing the accuracy of clinical testing of CD4+ and CD8+ T lymphocyte count.
  
  
  METHODS
  Blood from 34 HIV carriers/AIDS patients, were kept at 4 degrees C for 2, 24, 48, or 72 h, and tested for CD4+ and CD8+ T lymphocyte count using cytometric analysis. Part of the blood was processed, and kept at degrees C or room temperature for 2, 24, 48, or 72 h, then tested for CD4+ and CD8+ T lymphocyte count. The results were compared statistically in parallel.
  
  
  RESULTS
  Whole blood and processed samples preserved at degrees C showed no statistical difference in CD4+ T lymphocyte count among different preserving durations (P greater than 0.05), but CD8+ T lymphocyte counts were significantly different at 72 h (P less than 0.05). Processed samples at 72 h were significantly different in CD4+ T lymphocyte count(P less than 0.05), and significantly different in CD8+ T lymphocyte count at 24 h (P less than 0.05). At room temperature, samples at different duration were not significantly different in CD4+ T lymphocyte count, but significantly different in CD8+ T lymphocyte count at 48 and 72 h (P less than 0.05).
  
  
  CONCLUSIONS
  There were stable results for performing analysis of the CD4+ and CD8+ T lymphocyte count of the anticoagulated blood within 48 h. At room temperature, there were stable results for performing the analysis of CD4+ and CD8+ T lymphocyte count of processed samples within 24 h. Between 24 h and 48 h, although CD4+ count was stable, CD8+ count showed significant changes, so the ratio of CD4 to CD8 changed accordingly.
authors.affiliation: National AIDS Reference Laboratory, National Center for AIDS/STD Control and Prevention. Beijing 100050, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Xiao
authors.forename: Gui-yun
authors.initials: GY
authors.lastname: Zhang
authors.forename: Li-jian
authors.initials: LJ
authors.lastname: Pei
authors.forename: Ke
authors.initials: K
authors.lastname: Zhang
authors.forename: Yong-hong
authors.initials: YH
authors.lastname: Zhang
authors.forename: Yi
authors.initials: Y
authors.lastname: Feng
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000328:Adult; D000368:Aged; D001793:Blood Preservation / Q000379:methods*; D018791:CD4 Lymphocyte Count; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology*; D005260:Female; D005434:Flow Cytometry; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013696:Temperature; D013997:Time Factors