(E) YTS KIR2DL1 cells were pretreated with either SHP-1 and Cbls siRNA-loaded NPs, or N.S siRNA-loaded NPs. After 48 hours, cells were incubated with [35S] Met-loaded 721.221 Cw4 or Cw7 target cells. After co-culture for 5 hours, the supernatant was collected, and radioactive signal was measured. Data are means ± SEM of seven independent experiments. . (n=7). P values were calculated by One way ANOVA following Tukey's post hoc analysis and are indicated by asterisks **P < 0.01 ****P<0.0001. 