CD70 and viral infectious disease: The spectrum of viral infections seen in CD70-deficient patients is reminiscent of those in other patients with NK-cell deficiencies (e.g., GATA2 and FCGR3A mutations) presenting with susceptibility to Herpesviridae virus infection due to defect in targeted NK-cell-mediated defenses by downmodulating major histocompatibility complex (MHC) class 1 (56).