Accuracy of lymphocyte counts from UniCel DxH 800 in β-thalassemia/HbE patients having various numbers of nucleated red blood cells

Abstract

Background:The UniCel® DxH-800 is an automated cell counter widely used in laboratories. However, the effects of increased nucleated red blood cells (NRBCs) on the lymphocyte counts obtained using the UniCel DxH-800 have not been fully elucidated.Objective: The study's objective was to compare lymphocyte counts obtained using the DxH-800 and those obtained using flow cytometry in various ranges of NRBCs. Methods:This cross-sectional study analyzed 25 healthy volunteers and 69 β-thalassemia/HbE patients. The numbers of lymphocytes were determined using a UniCel DxH-800 and a standard flow cytometer using counting beads.Results: In healthy volunteers, regression analysis of the lymphocyte counts using the two approaches showed an r 2 0.85 and a p < 0.0001, and a Bland-Altman plot showed mean bias of +264 cells/μL. In β-thalassemia/HbE patients, regression analysis of the lymphocyte counts obtained using an automated cell counter and a flow cytometer showed an r 2 of 0.06, a p = 0.028, and a Bland-Altman plot showed the mean bias of +1,509 cells/μL. In addition, a high degree of discrepancy in the lymphocyte counts was observed in β-thalassemia/HbE patients who had NRBCs > 100,001 cells/μL. Conclusions:The present study demonstrated that the UniCel DxH-800 performed well in enumerating lymphocytes in specimens that contained various numbers of NRBCs. However, a high number of NRBCs may interfere with lymphocyte counts obtained using the counter.

Noninvasive prenatal diagnosis targeting fetal nucleated red blood cells

“…These fNRBCs need to be released before the downstream identification of the fetal origin and clinical analysis. Common release methods include three major categories: (1) biochemical methods such as DTT [ 154 ], MMP-9 [ 14 ], oxalic acid solution [ 38 ], DNA hybridization [ 177 ]; (2) physical methods such as electrical stimulation [ 30 ], magnetic field stimulation [ 170 ], photo-stimulation [ 179 ]; (3) laser microdissection techniques [ 180 ]. Since highly specific antibody proteins for fNRBCs have not yet been found, three-immunofluorescence identification makes it difficult to distinguish nucleated erythrocytes from the fetus and mother.…”