Purified CD34⁺ cells with the highest CD9 expression are committed toward either B lymphoid (CD19⁺) or megakaryocytic (CD41⁺) lineages.

CD34⁺ cells were purified from human bone marrow, stained, and analyzed for the expression of CD9 and of various differentiation markers. Two gates were drawn by selecting either CD34⁺ cells with a high FS/SS value (R1 region) or CD34⁺ cells with a low FS/SS value (R2 region). A third region, R3, corresponding to CD34⁺ cells, was drawn on a second CD34-PerCP/CD9-APC dot plot gated on R1. The quads were set up on the isotype-matched controls dot plot. Plots shown are for one experiment representative of 10 performed using different CD34⁺ bone marrow samples.