Fig 1: Data Exploration and Identification of Immune Cell Subsets in Peripheral BloodPBMCs were stained with the indicated set of antibodies (see Table S1) and analyzed by mass cytometry.(A) Cells were pre-gated as non-beads, DNA+, single, live, CD45+, CD235ab/CD61−, non-neutrophils (see Figure S1). The major immune lineages and certain subsets are identified through the indicated series of gating steps.(B) Median frequencies ± SEM in PBMCs from healthy donors (n = 5).(C) Exemplary identification of immune cell subsets, pre-gated on the indicated populations. Treg cells can be identified as CD25high CD127low, FoxP3pos, or a combination thereof.(D) Assessment of expression levels of important checkpoint and activation molecules on various immune cell populations. Expression was induced by stimulating cells with anti-CD3, anti-CD28-coated beads for 2 days.