Stimulating surface molecules, Th1-polarizing cytokines, proven trafficking-a new protocol for the generation of clinical-grade dendritic cells

Background aims. Dendritic cells (DC) have been vigorously investigated as an immunological basis for therapeutic vaccination against cancer and infections, even among patients after allogeneic stem cell transplantation. Methods. Effective induction of cell-mediated immunity strongly depends on the ability of DC to (i) migrate to the draining lymphoid organs mediated by chemokine receptors, (ii) prime T cells through high expression of costimulatory molecules and major histocompatibility complexes and (iii) secret Th1-polarizing cytokines such as Interleukin-12 (IL-12). However, there is no protocol to generate fully matured and functional DC according to methodical requirements of current good manufacturing practice (CGMP) guidelines. Results. We established a protocol conforming to CGMP standards that permits the generation of fully matured and functional DC on the basis of cell culture in adherence bags with the use of serum-free media with a maturation cocktail, containing tumor necrosis factor-alpha/Interferon-alpha/polyinosinic:polycytidylic acid. Our DC superiorly display three critical features for an effective induction of cell-mediated immunity without evidence of exhaustion, along with its ability to prime infectious or tumor-specific T cells in a short-term cell culture. Conclusions. Our newly developed protocol offers an attractive method to produce fully matured Th1-polarizing DC with proven migratory and stimulatory capacity for any clinical application according to CGMP standards.