In vivo generation of Dendritic cells by electro-gene transfer

Since the discovery of Dendritic cells (DCs) in 1975, their role as potent antigen presenting cells has been a field of intense interest and research. Candidate DC vaccines take advantage of the role of DCs in one of two ways. The first technique relies on the in vivo isolation of DCs which are then subsequently employed directly as adjuvants. In the second method, hematopoeitic growth factors are added to stimulate the expansion and proliferation of these cells in vivo. Due to the dearth of DCs, research has focused on the addition of growth factors such as FLT3-L (fms-like tyrosine kinase 3-ligand) and GM-CSF (granulocyte/macrophage colony-stimulating factor) which have proven invaluable for the expansion of this cell type. The goal of our study has been to deliver these growth factors intramuscularly using a plasmid vector. This work has shown that DCs are efficiently generated in vivo following a single intramuscular co-injection of cDNA encoding GM-CSF and FLT3-L