CD44 identifies clonogenic hematopoietic progenitors. (A) Expression levels of genes encoding cell surface markers, CD33, CD44, and CD18 that were associated with the naïve progenitor clusters. (B) Scatterplot of the flow cytometry profile of naïve 1A, 1B, and 2 cells at day 13 of differentiation (hiPSCs-SFCi55). Cells were gated on CD235a⁻CD43⁺CD33⁺. (C) Schematic of the chimeric culture system, using the ZsG reporter to trace cells during the differentiation process. SFCi55-ZsG and parental SFCi55 line were differentiated in a synchronous manner. At day 10, naïve 1 and 2 cells were sorted and cocultured with the parental line differentiation. Coculture was then analyzed at day 13. (D) Representative flow cytometry profile of the day 13 naïve descendants’ cells after sorting at day 10 and chimeric coculturing of naïve 1 and 2 cells. Contribution of naïve 1 and 2 to the naïve 1A, 1B, and 2 compartments (n = 6; multinomial logistic regression. *P < .05; **P < .01; ***P < .005). (E) CFU-C analysis of FAC-sorted naïve 1 and 2 hiPSCs-SFCi55 cells from day 10 (n = 3; paired Student t test. P = .0753). (F) CFU-C analysis of FAC-sorted naïve 1A, 1B, and 2 cells from day 13 (n = 9; Holm-Sidak test. ***P ≤ .001; hiPSCs-SFCi55). (G) HES3-RUNX1-GFP expression in naïve 1 and 2 cells at days 10 and 13 (n = 12; paired Student t test. *P < .05; **P < .01).