Ferreras Colino, ElisaMoreno, InmaculadaGortázar, ChristianSevilla, IkerAgulló Ros, IreneDomínguez Rodríguez, Lucas JoséJuste, RamónRisalde, Maria A.Domínguez, Mercedes2024-08-192024-08-192023-09Ferreras-Colino, E., Moreno, I., Gortázar, C., Sevilla, I., Agulló-Ros, I., Domínguez, L., Juste, R., Risalde, M. A., & Domínguez, M. (2023). Oral immunization with heat-inactivated Mycobacterium bovis reduces local parasite dissemination and hepatic granuloma development in mice infected with Leishmania amazonensis. Research in veterinary science, 162, 104963. https://doi.org/10.1016/j.rvsc.2023.1049630034-528810.1016/j.rvsc.2023.104963https://hdl.handle.net/20.500.14352/107484Author contributions Concept formulation: MAR, CG, IM, MD, IS, RJ, LD. Methodology: EFC, IM, MD, IAR, MAR. Data analysis: EFC, IM, MD. Writing the original draft: EFC. Editing: MAR, CG, IM, MD, IS, RJ, LD, IAR. Funding acquisition: CG, MAR. All authors read and approved the final manuscript.Aiming to explore whether oral immunization with heat-inactivated Mycobacterium bovis (HIMB) protects mice against Leishmania infection, 18 female BALB/c mice were randomly assigned to the immunized group, that received oral HIMB, or the control group, and were infected by inoculation of 10,000 Leishmania amazonensis promastigotes in the footpad. Spleen culture was positive in 55.55% of immunized mice and in 100% of control mice (p = 0.082). The number of immunolabeled amastigotes number in the popliteal lymph node was lower in the immunized group (p = 0.009). The immunized group presented fewer mature granulomas in the liver (p = 0.005) and more Lys + macrophages (p = 0.002) and fewer CD3+ T lymphocytes (p < 0.001) per hepatic granuloma. We conclude that immunization with HIMB via the oral route limited local parasite dissemination and hepatic granuloma development in mice challenged with Leishmania amazonensis through stimulation of macrophages, which is compatible with trained immunity.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article10.1016/j.rvsc.2023.10496337517297open access636.09Heat-inactivated Mycobacterium bovisLeishmaniaLiverMacrophagesTrained immunityVeterinaria3109 Ciencias Veterinarias