NK-cell cytotoxicity and degranulation in FHL5 patients. (A-B) Resting PBMCs or (C-D) PBMCs stimulated for 72 hours with IL-2 from healthy adult and infant donors or FHL5 patients were evaluated for cytotoxicity and degranulation toward K562 cells. (A,C) NK-cell cytotoxicity evaluated in a 4-hour 51Cr-release assay. Plots show LU calculated at 25% lysis, with boxes indicating 25th, 50th, and 75th percentiles and error bars representing SD. For FHL5 patients, each point represents one person. (B,D) NK-cell degranulation evaluated in a 2-hour flow cytometric assay. The cells were stained with fluorochrome-conjugated anti-CD3, anti-CD56, and anti-CD107a monoclonal antibodies. Lymphocytes were gated on forward/side scatter plots, followed by gating on CD3 versus CD56 plots. Plots show induced CD107a surface expression (ΔCD107a+) on CD3−CD56+ NK cells, with boxes indicating 25th, 50th, and 75th percentiles and error bars representing SD. For FHL5 patients, each point represents 1 person and is representative for at least 2 independent experiments.
