There is a growing interest in generating dendritic cells (DCs) for using as vaccines. Several cytokines, especially stem cell factor (SCF) and FLT3-ligand (FL), have been identified as essential to produce large numbers of myeloid precursors and even to increase DC yield obtained by the action of granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor alpha (TNF-α). However, there are few studies on the effect of the early-acting cytokines, commonly used to expand CD34+ progenitor cells, on DC generation.

We have established a serious of functional analysis of maturated or immaturated DCs including surface markers screening or cytokine production. Here, we design this two-year project to evaluate the possible methodology in the generation of CD14+CD1a- and CD14- CD1a+ myeloid DC precursors from CD34+ cells. In the first year of the project, we will set up the standard protocol to generate DC precursors from cord blood stem cells. In the first step, we will isolate CD34+ cells from cord blood and amplify these cells. Purity of the CD34+ cell populations obtained will be greater than 90%. In the next step, these primary cultures of CD34+ cells will treat with early-acting cytokines such as GM-CSF and IL-4 to further induction into dendritic cells. Functional analysis of dendritic cells would be performed in this stage. In the second year of the project, we will further evaluate the induction of DCs by CD34+ stem cells could be affected by combination of mesenchymal stromal cells. These results of this research with CD34+-based DCs induction provide the basis for materials to develop the DC-based vaccine against viral and fungal infections, and might be a powerful tool in anti-tumor immunotherapy.