Costimulation molecule expression and subset distribution of blood dendritic cells in normal children and newly diagnosed pediatric leukemia and lymphoma patients.

Objective: To characterize dendritic cell (DC) numbers, subset distribution, phenotype, and costimulation molecule expression in a normal pediatric population and in a lymphoblastic malignant pretherapy pediatric population. DC are potent antigen-presenting cells and are crucial for initiating specific immune responses.

Materials And Methods: We first analyzed peripheral blood samples of healthy pediatric controls (n=72).

Results of a Phase I study utilizing monocyte-derived dendritic cells pulsed with tumor RNA in children with Stage 4 neuroblastoma.

Background: A Phase I study of 11 pediatric patients with newly diagnosed, Stage 4 neuroblastoma was conducted using monocyte-derived dendritic cells (DC) pulsed with tumor RNA to produce antitumor vaccines (DC(RNA)).

Methods: Patients received two courses of induction with carboplatin followed by standard chemotherapy, surgery, radiation, high-dose therapy, stem cell rescue, and DC(RNA) vaccine therapy.

Results: The results showed that this method for producing and administering DC(RNA) from a single leukapheresis product was both feasible and safe in this pediatric neuroblastoma population.

Results of a phase 1 study utilizing monocyte-derived dendritic cells pulsed with tumor RNA in children and young adults with brain cancer.

We conducted a phase 1 study of 9 pediatric patients with recurrent brain tumors using monocyte-derived dendritic cells pulsed with tumor RNA to produce antitumor vaccine (DCRNA) preparations. The objectives of this study included (1) establishing safety and feasibility and (2) measuring changes in general, antigen-specific, and tumor-specific immune responses after DCRNA. Dendritic cells were derived from freshly isolated monocytes after 7 days of culture with IL-4 and granulocyte-macrophage colony-stimulating factor, pulsed with autologous tumor RNA, and then cryopreserved.