Evaluation of immunomodulatory potential of synthetic TLR7 Agonist p-IMDG in the chicken peripheral blood mononuclear cells

Abstract

Recent developments in immunology have made it possible to create new molecular adjuvants that improve adaptive responses by modifying innate immune pathways.. Among pattern recognition receptors, Toll-like receptors (TLRs) are key mediators of host innate immunity. This study evaluated the immunomodulatory potential of p-IMDG, an imidazoquinoline derivative in the chicken. This molecule was previously shown to activate TLR7 in human HEK293 reporter cells and induce strong antibody responses in mice. The chicken peripheral blood mononuclear cells (PBMCs) were stimulated with p-IMDG to assess cytokine gene expression profiles using qRT-PCR. The compound induced a biphasic IFN-γ response indicating both direct and feedback-driven activation. IFN-β showed moderate induction, while IL-13 displayed a marked late increase, suggesting a mixed Th1/Th2 response. IL-4 expression was transient and low. p-IMDG exhibited no haemolytic activity, confirming its in vitro safety. Overall, p-IMDG effectively stimulated antiviral and immunoregulatory genes in the chicken PBMCs, highlighting its potential as a novel TLR7-based adjuvant candidate for poultry and other veterinary vaccines. Further in vivo studies are needed to validate its efficacy and safety.