Publications & Reports

Evaluation of the blood stabilizers TransFix and Cyto-Chex BCT for low-cost CD4 T-cell methodologies.

Plate MM, Louzao R, Steele PM, Greengrass V, Morris LM, Lewis J, Barnett D, Warrino D, Hearps AC, Denny T, Crowe SM
1 AIDS Pathogenesis and Clinical Research Program, Burnet Institute for Medical Research and Public Health, Melbourne, Australia.


TransFix™ and Cyto-Chex(®) BCT (blood collection tube) reagents have been shown to maintain whole blood integrity for delayed immunophenotyping by flow cytometry. We evaluated the ability of these blood-stabilizing reagents to preserve HIV-seropositive blood for delayed CD4(+) T-cell quantification utilizing the Dynal(®) Biotech T4 Quant Kit. TransFix was added to EDTA-anticoagulated whole blood and tested at a 1:10 dilution over 7 d using the Dynal (n = 21) manual method. Compared to baseline analysis, a significant decrease in mean CD4(+) counts was observed over time. Cyto-Chex BCT-preserved samples (n = 20) were tested for CD4(+) counts by Dynal over 7 d, with storage at varying temperatures: room temperature (21 degrees C), 37 degrees C, and 37 degrees C with intermittent storage at 42 degrees C. A significant decline in mean CD4(+) counts was observed in samples at all temperatures compared to baseline (p < 0.05). Increases in temperature to and above 37 degrees C resulted in a greater decline in mean CD4(+) counts over time. Our findings indicated that neither TransFix or Cyto-Chex BCT was a suitable blood stabilizer when used for delayed CD4(+) quantification with a low-cost manual CD4(+) bead-based method.


  • Journal: Viral Immunology
  • Published: 01/10/2009
  • Volume: 22
  • Issue: 5
  • Pagination: 329-332