Polymer-Mediated DNA Vaccine Delivery to Bystander Cells Leads to Efficient Cross- Presentation by Dendritic Cells and Subsequent Cross-Priming of T Cells

摘要

Direct targeting of dendritic cells is an ideal goal for DNA vaccine delivery in order to stimulate both arms of the immune system. However, dendritic cells are a rare cell type and are often difficult to transfect by nonviral polyplexes. Here we show that transfecting bystander cells such as fibroblasts alone by PEI/DNA complexes leads to efficient cross-presentation of a model antigen by dendritic cells and subsequent activation of antigen-specific CD8+ T cells. Such an outcome depends on a proper balance between transfection efficiency and polyplex-induced toxicity in the fibroblasts. This study illustrates a new pathway of polymer-based DNA vaccine delivery without direct targeting of antigen-presenting cells.