In this regard, several studies have shown that triggering of different activating receptors, such as DNAX accessory molecule-1 (DNAM-1), NK group 2D (NKG2D) and Natural Cytotoxicity Receptors (NCRs), is involved in the recognition and killing of MM cells by NK cells [9-11]; moreover, MM cells can express the DNAM1-ligands (DNAM1Ls) PVR/CD155 and Nectin-2 (Nec-2) [12] and the NKG2D-ligands (NKG2DLs) MICA/B and ULBPs on the cell surface [9,12,13]. Here, PVR is linked to Miyoshi myopathy.