In vitro stimulation of human influenza-specific CD8+ T cells by dendritic cells pulsed with an influenza virus-like particle (VLP) vaccine.

The purpose of this in vitro study was to determine if a virus-like particle (VLP) influenza vaccine stimulated human CD8+ T cells in a dendritic cell (DC): T cell co-culture system. VLP-pulsed DCs were co-cultured with autologous CD8+ T cells from five donors. Functional CD8+ T cells were detected via cell surface and intracellular cytokine staining. T cells from four of the five donors showed ≥2-fold increase over background in the % activated CD8+ cells. These results indicate that the influenza VLP vaccine can stimulate CD8+ T cells via DC antigen presentation, likely through the MHC-I pathway, thus broadening the immunological response induced by this promising influenza vaccine.