Accumulation and terminal differentiation of the CD56^dim NKG2A⁺ KIR⁻ NK-cell subset during acute IM. PBMCs from controls and IM patients were analyzed by flow cytometry. (A) Frequencies of CD56^dim NKG2A⁺ KIR⁻ NK cells within the CD56^dim population from representative healthy control, IM-acute, 1-month, and 6-month patients. Frequencies of (B) CD56^dim NKG2A⁺ KIR⁻ and (C) CD56^dim NKG2A⁻ KIR⁺ NK cells in healthy EBV-negative controls (n = 17), healthy EBV-positive controls (n = 20), IM-like patients (n = 12), and IM-acute (n = 17), 1-month (n = 11), 6-month (n = 10), and 2-year (n = 4) patients. Frequencies of CD57⁺ cells within (D) the CD56^dim NKG2A⁺ KIR⁻ and (E) the CD56^dim NKG2A⁻ KIR⁺ NK-cell subsets in healthy EBV-negative controls (n = 17), healthy EBV-positive controls (n = 20), and IM-acute (n = 17), 1-month (n = 11), 6-month (n = 10), and 2-year (n = 4) patients. Horizontal lines or single symbols indicate median values. Error bars indicate interquartile ranges. Mann-Whitney U tests.