TPO and chronic myelogenous leukemia, BCR-ABL1 positive: Therefore, we assessed the viability of primary human CD34+ CML stem/progenitor cells isolated from the peripheral blood of seven untreated CML patients in chronic phase of the disease and treated for 96 h with either of the drugs or their combination in ex vivo liquid cultures in the absence (Fig. 7A and Supplementary Fig. 3A, left panels) or presence (Fig. 7A and Supplementary Fig. 3A, right panels) of the early acting cytokines SCF, FL and TPO [33].