Long-Term Whole Blood Stabilization Preserves Immune Phenotypes for Multiparameter Cytometry

Multiparameter cytometry enables comprehensive characterization of immune populations and phenotypes in clinical samples. However, conventional whole blood workflows typically require processing within 24–72 hours of collection, creating logistical challenges for multicenter clinical trials and potentially introducing variability associated with sample shipment and processing delays.

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TokuKit is a three-step, centrifuge-free whole blood preservation method designed to support sample storage at –80°C for up to 24 months, enabling samples to be stabilized at the collection site and analyzed later at a centralized laboratory.

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To evaluate long-term preservation of immune phenotypes, whole blood from three healthy donors was analyzed fresh or following TokuKit stabilization and storage for 1, 3, 9, 15, 18, and 24 months using a 41-marker mass cytometry panel supporting analysis of up to 735 immune cell subsets and states. At 24 months, frequencies across 36 immune cell populations remained highly concordant with same-week stabilized samples (R > 0.99), while functional marker-defined subsets demonstrated similarly strong concordance (R = 0.96). These data support evaluation of long-term whole blood stabilization as an approach for centralized and longitudinal immune profiling.

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