Comparing two automated high throughput viable-cell counting systems for cell culture applications

•Accurate measurement of cell density and viability by a flow cytometer.•High throughput cell count analysis in a short time.•Excellent tool for routine monitoring of cell culture process. Cell counting and viability assessment is an integral part of mammalian cell line development. While manual counting with a hemocytometer is still the gold standard method, its subjectivity and high labor intensity has resulted in its reduced use in favor of automated systems. In addition, some of these automated systems offer multiwell plate based high throughput cell count, which is an asset for biopharmaceutical companies generating hundreds of high-performance cell lines per year. In this study, we used Chinese Hamster Ovary (CHO)-K1 cells cultured in suspension in order to evaluate two automated viable-cell counters, the Guava® easyCyte HT and the CytoFLEX®, for their performance in monitoring Viable Cell Density (VCD) and viability. Our results show that specificity, accuracy, precision and repeatability was comparable between the two systems and when compared to manual counting, thus providing efficient alternatives particularly when analyzing high sample numbers in a daily mode.