Ex vivo generation of dendritic cells from CD34+ cells in gas-permeable containers under serum-free conditions

Dendritic cells (DC) are efficient and potent APCs that can be generated ex vivo. For them to be used clinically, however, a closed culture system using serum-free medium should be used. Our goal was to differentiate DC from human blood CD34+ cells in serum-free media in a new gas-permeable culture container, PL2417. Apheresis products were collected from healthy G-CSF-mobilized donors, and CD34+ cells were selected using the Isolex immunomagnetic cell selection system. Cells were cultured in the presence of GM-CSF and tumor necrosis factor-alpha (TNF-alpha) in various serum-free media and compared with serum-containing medium in 4-well plates. One of the serum-free media was then selected and used in PL2417 containers and compared with serum-containing medium in standard flasks. The cells were evaluated at days 0, 7, and 14 for the presence of DC, which were identified morphologically after Wright-Giemsa staining by cytoplasmic processes extending from the surface of the cell. The cultures were evaluated phenotypically by flow cytometry and immunohistochemistry. The stimulatory capacity was examined in MLR. Overall, results from serum-free media and PL2417 containers were comparable results obtained under the other conditions. These data indicate that culture-deriving DC from CD34+ cells in PL2417 closed system containers using serum-free media is as effective as using standard flasks and serum-supplemented media.