METHODS: We determined the performance characteristics of 4, 5, and 6-color protocols for white blood cell (WBC) and one and two-color protocols for red blood cell (RBC) evaluation for different PNH target clones and compared results from PNH patient analysis.
RESULTS: Coefficient of variation (CV) for precision/reproducibility analysis ranged from 0.01%/0.12% to 2.56%/ 3.59% for granulocytes, from 0.07%/0.08% to 3.87%/11.61% for monocytes and from 0.4%/1.02% to 6.53%/ 5.1% for RBCs within different approaches and target PNH clones. Comparison of individual protocols revealed excellent correlation (r = 0.99), Wilcoxon rank tests found no statistically significant differences (p > 0.05), Bland-Altman analysis proved agreement for all PNH clones (mean bias ranging from 0.02 to 2.2).
CONCLUSIONS: Our results confirm good intralaboratory characteristics for precision and reproducibility analysis, excellent correlation and agreement between approaches underlining the primary role of optimally selected glycophosphatidylinositol (GPI)-specific reagents and secondary role of number, type of gating reagents and gating strategy.