Extended Data Fig. 4: CD45 vs. side scatter in clinical sample gating.

a, In clinical flow cytometry, a laser beam is shot through each individual cell as it passes through the cytometer. Granules – especially within neutrophils, eosinophils, and monocytes – refract and reflect some of the light perpendicularly, which is measured by a side scatter (SSC) detector. When plotted on a “map” of SSC vs. CD45, a neutrophil (top cell) plots high on the SSC axis (purple shaded region), while a lymphocyte (bottom cell) plots low (green shaded region). b, Events from the regions defined on the SSC vs. CD45 plot are then graphed on daughter biaxial plots. Typical monocytes express CD38 but not CD5 or CD19 (blue event cluster, top row). Lymphocytes include various subsets with various combinations of expression (green events, bottom row).