Validation of automated fluorescent‐based technology for measuring total nucleated cell viability of hematopoietic progenitor cell products

Background A reliable rapid method for measuring total nucleated cell (TNC) viability is essential for cell‐based products manufacturing. The trypan blue (TB) exclusion method, commonly used to measure TNC viability of hematopoietic progenitor cell (HPC) products, is a subjective assay, typically uses a microscope, and includes a limited number of cells. The NucleoCounter NC‐200 is an automated fluorescent‐based cell counter that uses pre‐calibrated cartridges with acridine orange and DAPI dyes to measure cell count and viability. This study describes the validation of the NC‐200 for testing HPC's viability. Methods Samples from 189 fresh and 60 cryopreserved HPC products were included. Fresh products were tested for viability after collection by both TB and NC‐200. 7‐aminoactinomycin D (7AAD) CD45+ cell viability results were obtained from a flow cytometry test. Cryopreserved products thawed specimens were tested for viability by both TB and NC‐200. The NC‐200 viability results were compared with the other methods. Acceptability criteria were defined as ≤10% difference between the NC‐200 method and the other methods for at least 95% of the samples. Results Fresh products' mean viability difference between NC‐200 and TB or 7AAD CD45+ method was 4.9% (95%CI 4.6–5.4) and 2.8% (95%CI 2.2–3.4), respectively. Thawed products' mean viability difference between NC‐200 and TB was 3.0% (95%CI 0.4–5.6). Conclusion The NC‐200 automated fluorescent‐based method can be used effectively to determine HPC's viability for both fresh and cryopreserved products. It can help eliminate human bias and provide consistent data and operational ease.