EVALUATION OF THE IMMUNOMODULATORY POTENTIAL OF POLY-ICLC (HILTONOL®) IN CANINE IMMUNE CELLS: an in vitro study

• Grant number: 24/09005-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2024
• End date: August 31, 2025
• Field of knowledge: Biological Sciences - Immunology
• Principal Investigator: Cristina de Oliveira Massoco Salles Gomes
• Grantee: Tamires de Assis Roberto Gomes
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The polyriboinosinic-polyribocytidylic acid (Poly-ICLC), also known as Hiltonol®, is a double-stranded RNA macromolecule that has demonstrated versatility in modulating the immune profile of humans in response to pathogens, both as initial therapy and as a complement in various diseases, including autoimmune, neoplastic, and infectiousdiseases. Its ability to induce type 1 interferons (IFN) cytokines and modulate the immuneNresponse by influencing bactericidal, tumoricidal, and virucidal activity has sparked interest in veterinary medicine, especially in dogs, where there are few studies on use of biological immunomodulatory. Poly-ICLC belongs to the group of biological response modifiers that act directly on immune mechanisms, potentially improving therapeutic conditions in cases where standard treatment is insufficient. Its immunostimulatorycapacity involves the activation of dendritic cells, NK cells, and macrophages, as well as the induction of pro-inflammatory cytokines and co-stimulatory molecules. In this context, the aim of the present project will be to investigate the in vitro effects of poly-ICLC (Hiltonol®) on different cells of the canine immune system. Using canine blood cells obtained from healthy donors and maintained in vitro treatment with different doses of Poly-ICLC (Hiltonol®), the following cellular profiles and functions will be analyzed: a) the proliferation of lymphocytes and the levels of IFN-gamma in the supernatant of blood lymphocytes; b) from monocyte-derived macrophages, their bactericidal capacity will be analyzed by measuring the number of colony-forming units (CFUs) in a phagocytosis assay with Staphylococcus pseudointermedius. These experiments aim to determine whether Poly-ICLC (Hiltonol®) is a promising therapeutic tool in the field of veterinary medicine, with potential for the treatment of infectious diseases in dogs and possibly in other species.