In particular, CMVs avoid expression of stress‐ or infection‐induced ligands for activating NK cell receptors on the surface of infected cells [14, 15], especially the ligands ULBP1, ULBP2, MICA, and MICB for the human activating NKG2D receptor [16, 17, 18, 19]. Here, ULBP1 is linked to infection.