Effect of FL on hematopoietic expansion in liquid culture. CD34⁺ CD38^dim cells from mobilized peripheral blood were cultured in [IL-3 + IL-6 + KL] ± FL. Cultures were terminated for analysis when sufficient cells had been generated (day 12, 5, and 6 are shown in the top, middle, and bottom panels, respectively). In the absence of FL, CD34⁺ cells were below detection in the top panel and CD34⁺ CD33^dim cells were below detection in the top and bottom panels. In each case, FL enhanced the number of total cells, CD34⁺ cells, and early CD34⁺ CD33^dim cells.