Disclosed is a pharmaceutical preparation comprising partially matured dendritic cells obtained by a method comprising the steps of: a) providing immature dendritic cells or precursor cells thereof or partially matured dendritic cells obtained by contacting immature dendritic cells with at least one dendritic cell maturation agent to produce partially matured dendritic cells as defined by their capacity to secrete IL-12, b) manipulating the cells of step a), in particular the partially matured dendritic cells releasing IL-12 of step a), to (i) over-express at least one immune molecule capable of maintaining the T-Iymphocyte stimulatory capacity of dendritic cells characterised by continued IL-12 secretion for at least 24 hours, preferably at least 48 hours, and selected from the group consisting of CD40L by introducing nucleic acid molecules encoding for said at least one molecule and/or (ii) inhibit or prevent the expression of at least one T-Iymphocyte suppressive molecule acting within dendritic cells exposed to a primary maturation agent or being released from dendritic cells exposed to a primary maturation agent and being selected from the group consisting of interleukin 10 (IL-10), indoleamine 2,3- dioxygenase (IDO), and the genes given in the tables 3, 4 and/or 5 of the specification, by knocking out the gene or a fragment thereof encoding said at least one T-Iymphocyte suppressive molecule or by introducing nucleic acid molecules, preferably ribonucleic acid molecules, to inhibit or prevent the expression of the at least one T-Iymphocyte suppressive molecule that is active within the dendritic cell or is delivered from the dendritic cells to T-cells.
