AKT signaling drives the 3GF-activated survival and division of primitive human hematopoietic cells. (A) Experimental design used to compare the 3GF-stimulated time course of signaling protein activation assessed by flow cytometric analysis. (B) Median relative shift in the intensity of the indicated marker from the corresponding unstimulated sample in CD49f⁺ cells exposed to 3GF for different times. Asterisks indicate significant differences from the unstimulated samples (∗P < .05; ∗∗P < .01; ∗∗∗P < .001; bootstrapped probabilities). Paired survival (C) and proliferation (D) effects of dimethyl sulfoxide (d)- or triciribine (t)-mediated inhibition of AKT activation. (E) Model of CD49f⁺ pathway activation after short-term 3GF stimulation. The length of the colored bars indicates the relative strength of activation of the indicated marker. CB responses are shown in navy, young adult in red, and aged adult in teal. (F) A model of the role of AKT signaling and other factors in regulating different stages of primitive human hematopoietic cell survival and proliferation.