Interestingly, regarding the T-cell functional markers, the portion of IFN-γ+, CD107a+, TRAIL+, and FasL+ cells after stimulation with PMA/Iono was significantly increased in the AT group compared with controls (IFN-γ: p = 0.0008, CD107a: p = 0.0057, TRAIL: p = 0.0054, FasL: p = 0.0166) (Figures 4A–D). Here, IFNG is linked to ataxia telangiectasia.