KLRC2 and hemorrhagic fever with renal syndrome: In this study, CD56dimCD16+NKG2A+ NK cells were the main subset in HFRS patients, showing activation and proliferation phenotypes with NKG2C-CD57- and the ability to secrete tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and cytotoxic mediators.