KIR3DL1 and Epstein-Barr virus infection: It has been reported that EBV infection induces the expansion of NKG2A+/KIR-/CD56dim NK cells [44],so the NK cells associated with ANKL in the current study may have originated from earlier stage NK cells, as their immunophenotype was NKG2A+/KIR-/CD56bright[45], which favors an EBV origin.