Development of a standardized protocol for reproducible generation of matured monocyte-derived dendritic cells suitable for clinical application.

There is increasing interest in the generation of dendritic cells (DC) for cancer immunotherapy. In order to utilize DC in clinical trials it is necessary to have standardized, reproducible and easy to use protocols. We describe here the process development for the generation of DC as the result of investigation of culture conditions as well as consumption rates of medium and cytokines. Our studies demonstrate that highly viable DC (93 +/- 2%) can be produced from CD14(+) enriched monocytes via immunomagnetic beads in a high yield (31 +/- 6%) with X-VIVO 15, 400 U ml(-1) GM-CSF and 2000 U ml(-1) IL-4 without serum and feeding. For the maturation of DC different cocktails (TNF-alpha, IL-1beta, IL-6, PGE(2) and TNF-alpha, PGE(2)) were compared. In both cases cells expressed typical surface molecules of mature DC and induced high proliferative responses in mixed lymphocyte reactions which led to IFN-gamma producing T-lymphocytes. The data suggest that the use of this optimized, easy to use protocol results in highly mature DC.