Overall, these data speak in favor of the preferential sensitivity of Tregs to IFN effects, and in particular with its anti‐proliferative (more than its pro‐apoptotic) functions, in line with what we observed in vivo in resting state in ISG15 deficiency, and in CHC patients undergoing pegIFN/ribavirin therapy.16 The gene discussed is ISG15; the disease is cryohydrocytosis.