Figure 4.

Ex vivo expansion of HSCs by co-culture with CD34^loCD133^lo cells. CD34^hiCD133^hi HSCs and CD34^loCD133^lo cells were purified from FL CD34⁺ cells by sorting. CD34^hiCD133^hi CB HSCs were purified from CB. Co-cultures were prepared by mixing HSCs and CD34^loCD133^lo cells at a ratio of 1:7. HSCs alone were used as a control culture. Non-adherent cells in the CD34^loCD133^lo cell co-cultures and control cultures were harvested at 4 and 7 days, counted, and analyzed for CD34 and CD133 expression. All the experiments were repeated twice. (A–C) FL CD34^hiCD133^hi HSCs and CD34^loCD133^lo cells were used for culture. (A) Representative CD34 versus CD133 staining profiles of cultured cells at day 4 and day 7 are shown. The number indicates the percentage of CD34^hiCD133^hi HSCs in the gated region. (B) The amount of total non-adherent cells, and (C) CD34^hiCD133^hi HSCs in culture. (D–F) FL CD34^hiCD133^hi HSCs and CD34^loCD133^lo cells were used for culture. Transwells were used to block cell–cell contact between HSCs and CD34^loCD133^lo cells. (D) Representative CD34 versus CD133 staining profiles of cultured cells at day 4 and day 7 are shown. The number indicates the percentage of CD34^hiCD133^hi HSCs in the gated region. (E) Numbers of total non-adherent cells and (F) CD34^hiCD133^hi HSCs in culture. (G–I) CB CD34^hiCD133^hi HSCs and CD34^loCD133^lo cells were used for culture. (G) Representative CD34 versus CD133 staining profiles of cultured cells at day 4 and day 7 are shown. The number indicates the percentage of CD34^hiCD133^hi HSCs in the gated region. (H) Numbers of total non-adherent cells and (I) CD34^hiCD133^hi HSCs in culture. Data are shown as the mean ± SEM of 2 independent experiments. *p <0.05.