Minimal residual disease (MRD) in chronic lymphocytic leukemia (CLL) has prognostic and predictive significance. One of the approaches to detect MRD by flow cytometry (FC) is the use of dry antibody reagents such as DuraClone® RE CLB (Beckman Coulter-BC). The aim of this study was to evaluate the performance of the DuraClone® RE CLB in detecting MRD in CLL compared to liquid reagents.
DuraClone® RE CLB is composed by CD81FITC, ROR1PE, CD79bPC5.5, CD19PC7, CD5APC, CD43APCA750, CD20PB, and CD45KrO. For the liquid reagent assay, we used CD43FITC, ROR1PE, CD3ECD, CD5PC5.5, CD20PC7, CD79bAPC, CD19APC750, CD81 APCH7, and CD45KrO. The liquid and dry tubes were used to detect 20 MRD-positive CLL samples. The samples were analyzed using Radar Plots Kaluza Software (BC).
The statistical correlation between the liquid and dry reagents was acceptable (R = .9583) and no discrepancy was observed in MRD percentages. The average of the total number of acquired events in DuraClone® RE CLB was 758.583 (362.632-2.290.387), which allowed accurate sensitivity for the FC assay. The lowest MRD frequency detected by DuraClone® RE CLB was 0.01%, corresponding to a cluster with 106 events in a total of 737.030. The radar plots allowed the discrimination between normal B-cell population and CLL cells.
The DuraClone® RE CLB method allowed the accurate detection of MRD in clinical and interlaboratorial CLL samples, thereby supporting the use of this method to potentially increase productivity, reduce pipetting-associated errors and cost, and allow better standardization.

© 2020 International Clinical Cytometry Society.