Figure 2.

Cell Cycle Progression of Human mPB CD34+ Cells in Ex Vivo Culture

(A) Representative flow cytometry plots for assessing cell cycle status in CD34+, CD34+ CD38+ (progenitors), and CD34+ CD38− (EE) populations. CD34+ cells were stained with antibodies against Ki67 and Hoechst 33342. G0: 2N DNA and Ki67 negative, G1: 2N DNA and Ki67 positive, S/G2/M: 4N DNA and Ki67 positive.

(B) Cell cycle status of CD34+ cells in ex vivo culture. Notably, ∼60% of bulk CD34+ cells are in G0 at day 0, and 100% of the cells are cycling by day 3.

(C) Cell cycle status of CD34+38+ progenitor cells in ex vivo culture. More than 50% of progenitor cells are cycling at day 0, and the percentage of cycling cells continually increase until day 3.

(D) Cell cycle status of CD34+38− EE HSPCs in ex vivo culture. Notably, ∼90% of the EE HSPCs are quiescent at day 0, and EE HSPCs gradually exit quiescence until day 3 where 100% of them are cycling.

Representative data from experiments performed with three different mPB donors and n = 2 biological replicates per donor.

See also Figure S2.