ML NK cells are highly functional ex vivo. NK cells from patient peripheral blood (A-B) and bone marrow (C-D) were unstimulated or stimulated with K562 in a standard 6-hour functional assay. (A) Representative data depicting IFN-γ and CD107a in unstimulated and K562-stimulated NK cells from P-ML007 peripheral blood at day 28. Numbers represent percentage of cells in the indicated gate. (B) Summary data from patient peripheral blood NK cells stimulated as in panel A indicated over time. Healthy donor NK cells (collected at screening) stimulated with K562 are included as representative of naive NK cell response. (C) Summary data for CD107a degranulation gated on CD56^dim (CD56^dim NKG2A^+/−) or ML (CD56^hi NKG2A⁺) NK cells in the same patient’s peripheral blood sample stimulated as in panel A. (B-C) Data are expressed as the mean ± standard error of the mean. (D) Representative data depicting IFN-γ and CD107a in unstimulated and K562-stimulated NK cells from bone marrow of P-ML007 at day 14. Numbers represent the percentage of cells in the indicated gate. (E) Summary data from bone marrow NK cells of each patient shown at day 14 stimulated as in panel D. (F) Summary data for CD107a degranulation gated on CD56^dim (CD56^dim NKG2A^+/−) or ML (CD56^hi NKG2A⁺) NK cells in same patient bone marrow sample stimulated as in (D). (B-C,E-F) Data were available for P-ML002, P-ML003, P-ML005, and P-ML007. Unstimulated and stimulated conditions were tested for normal distribution (Shapiro-Wilk) then compared by using 2-way analysis of variance (B-C) or paired t test (E-F). P-values are indicated above the graphs.