Comparison of interlaboratory variation in absolute T-cell counts by single-platform and optimized dual-platform methods.


BACKGROUND: Previous studies have reported that the adoption of a single-platform flow cytometry cell counting method resulted in lower interlaboratory variation in absolute T cell counts as compared to predicate dual-platform flow cytometry methods which incorporate independent automated lymphocyte counts (Schnizlein-Bick et al., Clin Diagn Lab Immunol 2000;7:336-343; Reimann et al., Clin Diagn Lab Immunol 2000;7:344-351). In the present study, we asked whether use of a single-platform method could reduce variation in absolute cell counts across the laboratories in the Multicenter AIDS Cohort Study (MACS) (n = 4), as suggested by the studies cited. METHODS: Identical study samples were shipped overnight to the MACS laboratories either by the National Institute of Allergy and Infectious Diseases, Division of AIDS Immunology Quality Assessment (NIAID- IQA) proficiency-testing program (n = 14), or by the Los Angeles site of the MACS (n = 10). For each sample, two tubes of blood were received; one was used for an automated complete blood count and differential, and the other for flow cytometry. The latter was performed using both our current dual-platform method (three-color CD45 gating and automated hematology) and the single-platform method (with TruCOUNT beads to generate the absolute counts). RESULTS: The median percent coefficients of variation (%CVs) for the dual-platform and single-platform methods were 6.6 and 9.9, respectively, for CD4 T cell counts, and 5.9 and 8.5, respectively, for CD8 T cell counts (n = 24). These differences were not statistically significant. The differences in absolute T-cell counts between the MACS sites and the median of all laboratories participating in the NIAID-IQA were smaller for the dual-platform than for single-platform absolute count method. CONCLUSION: In contrast to previous reports, we did not observe lower interlaboratory variation across the MACS sites for single-platform absolute lymphocyte subset counting relative to dual-platform methods. This result may be at least partly explained by the lower interlaboratory variation with the optimized dual-platform method in this study relative to the previous reports.





Published Version (Please cite this version)


Publication Info

Hultin, Lance E, Marianne Chow, Beth D Jamieson, Maurice RG O'Gorman, Frederick A Menendez, Luann Borowski, Thomas N Denny, Joseph B Margolick, et al. (2010). Comparison of interlaboratory variation in absolute T-cell counts by single-platform and optimized dual-platform methods. Cytometry B Clin Cytom, 78(3). pp. 194–200. 10.1002/cyto.b.20500 Retrieved from

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.

Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.