New POCT instrument, GBTsol ICA system for HIV monitoring by CD4 and CD8 enumeration in resource-poor settings

Abstract According to WHO report 39.0 million (33.1–45.7 million) people around the world were living with HIV infection till Dec of 2022. One method that we need for treatment and monitoring of HIV patients is CD4 counting and CD4/CD8 ratio. For this purpose, there are many different laboratory test with technical complexity and in other hand most of them are time consuming, expensive or cannot be used in resource limited places. This work demonstrates POCT microchip platform for enumerating leukocytes, CD4+ T- lymphocytes, and CD8+ T lymphocytes from whole blood, using fluorochrome-conjugated primary antibodies as a detection method. This device and its method omits all obstacles for WBC and CD4, CD8 T lymphocytes and it offers fast, cost effective and easy absolute WBC and CD4, CD8 T lymphocytes count for monitoring HIV patients’ immune situation with high accuracy which can be implemented insource limited stings or doctors’ office. We incubated Phycoerythrin (PE) conjugated primary antibodies specific to CD4 and CD8 antigens to enumerate CD4+ and CD8+ T cells, respectively. Comparison studies were performed with FACS count 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 0.67% to 12.78%, 0.81 to 13.68%, 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 0.91, respectively. Using Bland-Altman plots, a mean bias of 23, 38, and 490 cells/µL (95% CI, n=113) was obtained for CD4, CD8, and total leukocyte count, respectively. These data show that the GBTsol ICA (Immune Cell Analyzer) is comparable to the FACS count 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 with cheap, easy and fast way.