Agreement of lymphocyte subsets detection permits reference intervals transference between flow cytometry systems: direct validation using established reference intervals.

Objectives: With the increasing demand and application of lymphocyte subsets detection in clinical laboratories, different single-platform flow cytometer (FCM) systems have been developed. There is an urgent need to establish the reference intervals (RIs) for different single-platform FCMs and transferring them from one FCM system to another provides a much more feasible and convenient approach. This study aimed to explore the transferability of RIs for lymphocyte subsets across different flow cytometry platforms.

Methods: We first conducted the pairwise method comparison across four FCM platforms, including NovoCyte, BriCyteE6, DxFLEX, and FACSCantoII systems. Next, the transferability of RIs of lymphocyte subsets was evaluated. Furthermore, we conducted the RIs transference based on the FACSCantoII system, BriCyteE6 system and DxFLEX system, except for NK cells. The transferred RIs were further verified by calculating the bias (CV) between the established ones.

Results: The results of lymphocyte subsets detection based on the NovoCyte, BriCyteE6, DxFLEX, and FACSCantoII systems were comparable and it was feasible to transfer the RIs of lymphocyte subsets detected by the four FCM systems. The RIs of lymphocyte subsets detection using FACSCantoII, DxFLEX, and BriCyteE6 systems were established. Upon transferring the RIs of lymphocyte subsets from the FACSCantoII system to the BriCyteE6 system, and DxFLEX system except for NK cells, the CV between the transferred RIs and the established ones was below 20 % for all parameters.

Conclusions: The present study illustrated that the RIs of lymphocyte subsets could be transferred across different flow cytometry systems except for NK cells with different definition strategies.