Fig. 6.

Analysis of Wnt-mediated effects on HSC cell cycle status. (A Left) Representative cell cycle histograms obtained through propidium iodide (PI) staining of wild-type LKSI cells cultured for 4 days under control conditions (Left) or recombinant Wnt5a (Right). Histograms were analyzed as described in Materials and Methods. (Right) Average percentage of wild-type LKSI cells in S/G₂/M phases of the cell cycle after 4 days in culture. Data represent the average of three independent experiments for each condition. Error bars represent standard deviation. P values were generated by Student's t test. (B Left) Representative FACS analyses of G₀/G₁ LKSI cells after 4 days in culture under control conditions (Left) or recombinant Wnt5a (Right). LKSI cells in the G₀/G₁ phase were defined as cells with 2n DNA content as detected by 7-AAD staining (data not shown). G₀/G₁ cells were gated and analyzed for the percentage of cells that were in the G₀ phase, defined as Ki-67⁻. Regions were drawn based on isotype controls. (Right) Average percentage of wild-type G₀/G₁ LKSI cells in the G₀ phase after 4 days in culture. Data represent the average of three independent experiments for each condition. Error bars represent standard deviation. P values were generated by Student's t test. The approximate percentage of total cells in G₀ under control conditions, with Wnt3a, or with Wnt5a were 10%, 25%, and 35%, respectively (determined by multiplying the percentage of total cells in G₀/G₁ (A) by the percentage of G₀/G₁ cells in G₀ (B).