No lot-to-lot effects: TokuKit cytometry results remain consistent

Problem

Clinical trials often span years, possibly requiring blood collection across multiple lots of TokuKit buffers. As buffer lots age and new lots are introduced, clinical teams may worry that lot-to-lot differences could introduce variability into their cytometry results across a study.

Solution 

To assess lot-to-lot effects, we performed an experiment testing whole blood samples from three healthy donors processed using three TokuKit Buffer 1 lots with expiration dates approximately 6, 9, and 18 months from the date of processing. For each donor and lot, three replicates were prepared and stored at −80 °C. Samples were designated for analysis at 3 days, 3 months, and 6 months after collection. At the time of this release, the 3-day time point has been analyzed; samples for the 3- and 6-month time points are banked and will be analyzed in future releases.

All samples will be analyzed using a 41-marker mass cytometry panel to assess the frequencies of immune cell populations and functional marker subsets. 

For the 3-day timepoint, results showed highly consistent readouts across all TokuKit lots. The mean inter-lot coefficient of variation (CV) across immune populations and functional subsets was <6%: 3.53% for population frequencies, and 5.66% for functional marker subsets.

This data demonstrates that TokuKit delivers reliable and reproducible cytometry results regardless of buffer lot or expiration date, supporting long-running clinical trials without concern for lot-driven variability.

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