Cellular CD34 and CD13 expression and cell growth.

(A) Flow cytometry 2-color cytograms of culture day 5 cells: After labeling with FITC-CD1a, FITC-CD14, FITC-CD15, PE-CD13, and PCya5-CD34 mAb (left panel), Lin− cells were gated (R2) by excluding FITC-labeled cells; CD13 and CD34 expression of Lin− cells was then evaluated (right panel, with cell percentages indicated); fluorescence intensity is indicated along the 2 axes; data are from 1 experiment of 7. (B) Growth of day-5 sorted cells: after labeling as described in A, cells were sorted according to CD34 and CD13 expression after excluding FITC-labeled cells, and the sorted CD34⁺CD13^lo, CD34⁻CD13^lo, CD34⁺CD13^hi, and CD34⁻CD13^hi cells were cultured further for 7 days; cell recovery is presented as fold increase cell numbers over the number of initially seeded sorted cells; results are expressed as means ± SD (n = 6; with only 2 points examined on day 10).