KLRK1 and chronic myelogenous leukemia, BCR-ABL1 positive: However, the expression of NKG2D is well preserved in all NK cell subsets from TKI treated CML patients, with the exception of CD56bright from elderly patients, confirming recent studies showing that the downregulated expression of NKG2D at the time of CML diagnosis, is restored to normal levels after TKI treatment (40, 41).