Protocol for co-culture of murine bone marrow-derived dendritic cells with OT-I mouse CD8+ T cells to evaluate immune activation efficacy.

Preliminary evaluation of vaccine-induced immune activation can be performed with minimal animal use, in line with the principles of the 3Rs (replacement, reduction, and refinement) in animal experimentation. Here, we present a protocol to assess murine antigen-specific CD8+ T cell activation using a co-culture model of bone marrow-derived dendritic cells (BMDCs) and OT-I transgenic CD8+ T cells. We describe the steps for transfecting BMDCs with antigen-encoding mRNA formulations and assessing T cell responses after co-culture by intracellular cytokine staining and proliferation. For complete details on the use and execution of this protocol, please refer to Jiang et al.1.