Anna Greenshields

To the editor, Chimerism monitoring is central to post-allogeneic hematopoietic cell transplantation (HCT) management and informs clinical decisions including immunosuppression adjustment, donor lymphocyte infusion, and relapse surveillance [1, 2]. These decisions are frequently based on longitudinal changes in donor or recipient fractions, particularly in the setting of mixed chimerism and lineage-specific monitoring [3,4,5].

Intracellular dyes were used to allow increased multiplexing of our existing flow cytometry-based red blood cell (RBC) phenotyping assay. Intracellular staining was uniform, reproducible and had no impact on the ability to perform phenotyping for RBC antigens. The use of intracellular dyes is a simple way to greatly increase the throughput of flow cytometry-based RBC phenotyping methods.

Intracellular staining was used to create multiplexed flow cytometry-based antibody screen and identification panel assays. The antibody screen and identification panels achieved 100% concordance with expected results. Flow cytometry-based screens and identification panels could be utilized clinically as antibody detection methods. INTRODUCTION Flow cytometry is a widely utilized tool in both clinical and research laboratories [1].