Gating strategies for flow cytometric analyses and sorting. (A) FACS gating employed for (A) ratiometric analysis of cytoplasmic Ca²⁺ flux in primary T cells. (B) Immunophenotyping of T cells. TN: naïve; TSCM: stem cell memory; TCM: central memory; TM: transitional memory; TEM: effector memory; TD: terminally differentiated; CD27^dim: effector CD27^dim. (C) Enumeration of Tregs.