Immunogenic dendritic cells primed by social defeat enhance adaptive immunity to influenza A virus

Dendritic cells (DCs) sample their surrounding microenvironment and consequently send immunogenic or regulatory signals to T cells during DC/T cell interactions, shaping the primary adaptive immune response to infection. The microenvironment resulting from repeated social defeat increases DC co-stimulatory molecule expression and primes DCs for enhanced cytokine responses in vitro. In this study, we show that social disruption stress (SDR) results in the generation of immunogenic DCs, capable of conferring enhanced adaptive immunity to influenza A/PR/8/34 infection. Mice infected with influenza A/PR/8/34 virus 24 h after the adoptive transfer of DCs from SDR mice had significantly increased numbers of DbNP366-74CD8+ T cells, increased IFN-γ and IFN-α mRNA, and decreased influenza M1 mRNA expression in the lung during the peak primary response (9 days post-infection), compared to mice that received DCs from naïve mice. These data demonstrate that repeated social defeat is a significant environmental influence on immunogenic DC activation and function.

Research highlights
► SDR, a model of social defeat, significantly influences immunogenic DCs.
► Adoptively transferred DCs from SDR mice enhance adaptive immunity to influenza.
► SDR DC recipients have increased DbNP366-74CD8+ T cells in the lung after infection.
► SDR DC recipients have increased IFN-α and IFN-γ mRNA in the lung after infection.
► SDR DC recipients have decreased M1 mRNA in the lung after infection.