TNFRSF9 and telomere syndrome: Finally, total NK cells positive for functional activation-related receptors, particularly CD137 and HLA-DR, were also significantly increased in STS patients (1%, IQR: 1–2, N = 12; 11%, IQR: 3–20, N = 12; respectively) compared with CTRL (0.4%, IQR: 0.3–0.8, N = 21, p = 0.02; 2%, IQR: 1–3, N = 21, p = 0.02; respectively), once again indicating exposure to activating stimuli.