This work demonstrates a microfluidic platform for enumerating leukocytes (WBC), CD4+ T-lymphocytes, and CD8+ T lymphocytes from whole blood using fluorochrome-conjugated primary antibodies as a detection method. We incubated Fluorescein isothiocyanate (FITC) and Phycoerythrin (PE) conjugated primary antibodies specific to CD4 and CD8 antigens to enumerate CD4+ and CD8+ T cells, respectively. Comparison studies were performed with BD FACSCount to evaluate total leukocytes, CD4-T cell number, and CD8-T cell number in whole blood samples for monitoring the immune systems of patients with human immunodeficiency virus (HIV)/AIDS. Statistical analyses for precision, correlation, and agreement were performed. Coefficients of variation (CV) ranging from 0.6% to 10.74%, 0.86 to 10.46%, and 0.29% to 8.33% were obtained for CD4, CD8 and leukocyte recovery respectively. A significant correlation was found between the two assays for CD4 count and CD8 count, with correlation coefficients of 0.90 and 0.88, respectively. Using Bland-Altman plots, a mean bias of 24, 24, and 502 cells/µL (95% CI, n=200) was obtained for CD4, CD8, and total leukocyte count, respectively. These data show that the GBTsolTMICA (Immune Cell Analyzer) microfluidic platform method is comparable to the BD FACSCount dual platform method for measuring the amounts of CD4 T cells, CD8 T cells, and total leukocytes in blood samples for the purpose of monitoring HIV/AIDS patients.
Keywords: CD marker, POCT, Leukocyte, Sensitivity, Specificity, Medical device.