In the current proposal we are characterizing how DNA recognition by cytosolic DNA sensors coordinates activation of both the inflammasome and type I Interferon (IRF3) activated antiviral cascades. We are proposing the cytosolic DNA sensor protein AIM2 is pivotal to activation of both cascades. Using recombinant adenovirus vector infection of macrophage cell lines or primary cells, we are determining how triggering the DNA sensing machinery signals activation of the IRF3 type I interferon response and influences maturation of these antigen presenting cells. Based on preliminary data, we show that one of the essential downstream targets of the DNA sensor response is the adaptor protein STING. The scaffolds that support DNA sensor co-activation of inflammasome/STING targets will be examined. The current proposal presents the hypothesis that AIM2 is functioning to balance the antigen-presenting cell antiviral response. We have found that AIM2 which is an interferon inducible gene is also involved in regulating type I interferon sensitivity through STAT1. We are proposing an AIM2/STAT1 regulatory loop functions to control the inflammatory/IFN sensitivity of target immune sentinel cells. The studies presented in this proposal are targeting the immune recognition response pathways that are at the heart of the innate and adaptive immune response to recombinant adenovirus vectors. We are proposing these pathways are operating in a specific manner in immune cells. The knowledge gained from these studies will contribute to enhancing vaccine, gene therapy, and anticancer therapeutic applications and they will contribute to our ability to develop new treatments for viral infections and host DNA dependent autoimmune diseases. PUBLIC HEALTH RELEVANCE: Immune stimulating (is) DNA directly impacts immune function in DNA vaccines, DNA dependent autoimmune diseases and antiviral Immune responses. isDNA is a new and poorly understood area of the host (antiviral) immune response. In the current proposal we are investigating the DNA sensing networks triggered by rAdV infection of murine macrophages. Our research in this exciting and important area will contribute to immune modification strategies able to enhance the potency of DNA vaccines, enhance DNA vector gene transfer, or suppress DNA induced inflammatory diseases.