Clinical-scale production of granulocyte progenitor and post-progenitor cells using daniplestim, leridistim, Progenipoietin, Promegapoietin and autologous plasma

Background Supplementation of PBPC autografts with ex vivo expanded PBMC may significa ntly reduce or eliminate the period of neutropenia associated with high-dos e chemotherapy. Methods Unmanipulated growth-factor mobilized PBMC were expanded in media containin g daniplestim, leridistim, Promegapoietin, and Progenipoietin (DLPP) and 2% autologous plasma at 4 x 10(5) PBMC/mL, first in 25 cm(2) T-flasks, with s ampling on Days 7, 10, 13 and 15, and then in 1264 cm(2) Nunclon Cell Facto ries, with sampling on Days 7 and 13. Results In T25-flasks, maximal CFU-GM expansion ([38.2 +/- 9.5]-fold) occurred on D ay 10, whereas maximal total cell expansion ([6.7 +/- 1.1]-fold) occurred o n Day 15. Production of CD15+CD11b(-) and CD15(+)CD11b(+) granulocytic post -progenitors (3.0 +/- 0.4 x 10(6) and 3.7 +/- 0.9 x 10(-6), respectively) w as also maximal at Day IS Compared with the previously studied combination a Flt3L, PIXY321, G-CSF, GM-CSF and Epo, the DLPP cocktail performed simila rly, with the exception of yielding larger GM colonies at Day 10 and fewer granulocyte post-progenitors on Day 15. ln Cell Factories CFU-GM were expan ded (31.6 +/- 14.5)-fold, while total nonadherent cells were expanded (2.6 +/- 0.5)-fold. The two stack Cell Factory cultures seeded with 1.0 x 10(8) unselected PBMC produced approximately 3.3 x 10(6) CFU-GM and 1.3 x 10(8) m yeloid post-progenitors. Discussion Whereas expansion of cell numbers CFU-GM and granulocytic post-progenitors in Cell Factories mirrored that achieved in T25-flasks, future preclinical studies with the DLPP cytokine combination may be performed in small volume s, with subsequent translation to the larger volume Cell Factories. Suffici ent expansion can be achieved using the DLPP cytokine combination in the Ce ll Factories to provide the numbers of progenitors required for clinical tr ials.